# Fileset [proc-3rd-symp-fgm-3-246.xlsx](https://mdr.nims.go.jp/filesets/05723d2d-2ec6-4278-8d67-e2eb0f54d661/download) ## Creator National Institute for Materials Science ## Rights ## Other metadata [3rd International Symposium on Structural and Functional Gradient Materials　FGM'94　PROCEEDINGS (pp.3-246)](https://mdr.nims.go.jp/datasets/c38c4b33-e433-43b6-b86c-6abd010ac322) ## Fulltext Sheet1 BookTitle_j BookTitle_e Volume/Issue Issueddate Page Title_j Title_e AuthorList_j AuthorList_e Abstract Language 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 3-8 金属/セラミック傾斜材料の微細構造特性評価 MICROSTRUCTURAL CHARACTERIZATION OF METAL/ CERAMIC FUNCTIONALLY GRADIENT MATERIALS 渡辺龍三, 高橋純也, 川崎亮東北大学　工学部材料加工学科　仙台市 R. Watanabe, J. Takahashi and A. KawasakiDepartment of Materials Processing, Faculty of engineering Tohoku University. Sendai, Japan The quantification of microstructure of powder metallurgically processed functionally gradient materials has been carried out with particular emphasis on the microstructural connectivity involved within single material. Two dimensional measurements on the cross section, serial sectioning analysis and packing simulation have been employed for the microstructural characterization. The microstructural transition has been quantified using topological parameters (Betti number, genus and interface curvature), and in the light of percolation analysis. The relation between the multiconnectivity of the phases and their percolation cluster formation has been discussed on the basis of the experimental and simulation results. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 9-14 相互作用した成分を伴うシステムの液相焼結 LIQUID PHASE SINTERING OF THE SYSTEMS WITH INTERACTING COMPONENTS A. SavitskiiInstitute of Strength Physics and Materials Science, Tomsk, Russia A. SavitskiiInstitute of Strength Physics and Materials Science, Tomsk, Russia The major driving force for sintering of mixtures from components capable of forming solid solutions and intermetallic compounds is attributed to an alloy formation rather than free surface reduction. The general principle in the interaction between two components, one of them being a liquid, consists in the fact of d in the liquid occurs through diffusion of the solvent atoms from the liquid into the solid phase until the concentration of solid solution or that of an intermetallic compound in the surface layer enables them to pass into the liquid by means of melting. A multiparticle model of the two-component powder body is proposed to explain the discovered two sorts (S- and V-type) of concentration dependence of the changes of the compact volume during solid state sintering. If a two-component FGM is a transitional region between the pure components where the concentration changes from 0 to 100%, the shrinkage distribution inside this region as a result of sintering will depend on the concentration according to the S- or V-shaped curve. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 15-20 セラミックおよび金属/セラミック傾斜機能材料の作製へのマイクロ波処理の適用 APPLICATION OF MICROWAVE PROCESSING TO PREPARATION OF CERAMIC AND METAL-CERAMIC FGM M. willert-Porada, T. Gerdes, R. BorchertUniversity Dortmund, Department of Chemical Engineering, Dortmund, Germany M.Willert-Porada, T.Gerdes and R.BorchertUniversity Dortmund, Department of Chemical Engineering, Dortmund, Germany A heating method of general applicability for pressureless sintering of ceramic and metal-ceramic materials with a compositional gradient based on application of microwave radiation with 2.45 GHz frequency for heating is described. The mass ratio of metal to ceramic within a gradient material decides about the type of microwave cavity and casketing method necessary for successful microwave sintering. Besides microwave sintering of gradient materials the generation of a compositional or morphological gradient within an originally homogeneous material using microwave heating is addressed. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 21-26 水面下衝撃圧力を用いた粉体圧密技術による傾斜機能材料の作製 FABRICATION OF FUNCTIONALLY GRADIENT MATERIALS BY POWDER CONSOLIDATION TECHNIQUE USING UNDERWATER-SHOCK PRESSURE A. Chiba, M. Nishida, K. Imamura, T. Anraku, Y. Shintani and C. Moon熊本大学 A. Chiba, M. Nishida, K. Imamura, T. Anraku, Y. Shintani and C. MoonKumamoto University, Japan Three kinds of fully densified Functionally Gradient Materials (FGMs), i.e., Cu/SUS304, Ti/TiAl, and Si3N4/SUS304 systems, were fabricated by a newly developed underwater-shock consolidation technique without using any sintering additives. The experimental assembly of the shock consolidation consists of three parts, i.e., explosive charging, water chamber and powder charging parts. The energy of the shock wave increases by convergence due to the reduction of the cross section area of water chamber. The increased shock pressure and shock duration facilitate the consolidation of powders. The pressure level obtained was estimated to be 11 GPa. There were no cracks in the resultant compacts in which continuously compositional change was achieved. Microstructural aspects and thermomechanical properties of the FGMs were also described. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 27-32 粉末冶金によるFGMストリップの連続作製に関する先導的研究 PILOT STUDY RELATED TO THE CONTINUOUS FABRICATION OF FGM STRIP BY POWDER METALLURGY K.Dollmeier, B. Ilschner, W. ThieleInstitute of Technology, Materials Department Laboratory of Mechanical Metallurgy, Lausanne, Switzerland K. Dollmeier, B. Ilschner and W. Thiele Swiss FederalInstitute of Technology, Materials Department Laboratory of Mechanical Metallurgy, Lausanne, Switzerland The fabrication of graded specimens by P/M multilayer techniques is a well-known method. However, for industrial low-cost applications, batch processes tend to have serious disadvantages. The centrifugal P/M process as developed earlier by Delfosse and Ilschner [1] is already one step in the direction of rationalizing, but a continuous fabrication route must be the ultimate goal. In this study, the computer-controlled dosage system from the above-mentioned centrifugal installation is combined with a vibratory dispenser and a conveyor belt to form a feeding system for a continuous through-thickness gradient powder strip which is then sintered and finally hot or cold rolled. While the concentration gradient is primarily transversal, longitudinal changes of the profile along the length of the strip may easily be introduced as an additional feature. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 33-39 遠心粉末冶金法により製造された気孔サイズが傾斜した高多孔質焼結部材 HIGHLY POROUS SINTERED PARTS WITH A PORE SIZE GRADIENT MADE BY CENTRIFUGAL POWDER METALLURGY M. Joensson , M. KiebackTechnical University of Dresden, Germany M. Joensson and M. KiebackTechnical University of Dresden, Germany The effectiveness of high-porous sintered material is decisively influenced by the pore structure having to fulfill very different specific application conditions by variation of number, size and course of the open pore channels. The use of the Centrifugal Powder Metallurgy shaping method enables a variety of possibilities to combine different components and thus to get layered or gradient structures. By this way, different particle size fractions of stainless steel were combined in form of very thin active and carrier layers with and without gradient between them as well as in the form of one single gradient. The influence of geometry and arrangement of the powder particles and the binder system to sintering behaviour, permeability, separation capacity and strength were investigated, and the results compared with investigations on parts with homogenous structure and loose sintering parts. The results of the investigations of porous sintered parts demonstrates the advantage of this shaping method by the exploration of the influence of composition of powder components of the development of the pore structure. It was shown that the use of CPM facilitates the production of high-porous functionally gradient materials as well as the investigation of the influence of geometry and arrangement of the powder particles to sintering behaviour, permeability and separation capacity of the material. Furthermore, it was a main goal of this investigation to produce - via exactly controlled addition of powder components and binder material - pore structures which guarantee an improved retention efficiency without an essential increase in the loss of pressure. These results are supposed to permit the expansion of the spectrum of application of porous metal parts. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 41-46 ミクロ傾斜構造によるTiAl成分の合成 PROCESSING OF TiAl COMPONENTS WITH GRADIENT MICROSTRUCTURES J. Rosler、 C. TonnesABB Management Ltd., Corporate Research, Baden-Dattwil, Switzerland J. Rosler and C. TonnesABB Management Ltd., Corporate Research, Baden-Dattwil, Switzerland TiAl is, in principle, a very attractive material class for structural applications in the temperature range of 600deg.C-800deg.C because of its strength retention and low density. However, widespread application is hampered because it is presently not possible to achieve creep strength levels competitive with superalloys and ductility levels required for many engineering applications at the same time. So called fully lamellar microstructures exhibit high creep strength but poor ductility while duplex microstructures yield acceptable ductility levels of = 2 % but are combined with poor creep resistance. In this article, a novel approach is presented which allows the formation of microstructural gradients within one component so that requirements on ductility, e.g. in the root block of a turbine blade, and creep strength, e.g. in the airfoil section, can be satisfied at the same time. It utilizes powder metallurgy (PM) processing and the fact that the boundaries of the alpha-phase field can be shifted significantly by ternary alloying additions. The processing route, mechanical properties and possible application are discussed in this article. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 47-52 Crの傾斜化された添加物を伴う金属間NiAl化合物のP/M作製 P/M PREPARATION OF INTERMETALLIC NiAl COMPOUNDS WITH GRADED ADDITION OF Cr K. Barthel, N. Cherradi, B. IlschnerSwiss Federal Institute of Technology, Materials Department, Lausanne, Switzerland K. Barthel, N. Cherradi, and B. IlschnerSwiss Federal Institute of Technology, Materials Department, Lausanne, Switzerland Intermetallic NiAl compounds containing a graded addition of Cr are prepared by uniaxial hot pressing of multilayers. In the present work, the P/M fabrication method is described in detail. Intermetallic FGM specimens are characterized by microstructure, thermal properties and by composition and hardness profiles. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 53-58 様々な反応性粉末冶金法を利用した金属間傾斜材料の設計および製造 DESIGN AND PRODUCTION OF AN INTERMETALLIC GRADIENT MATERIAL BY USING A VARIANT OF REACTIVE POWDER METALLURGY F. Pirwitz、 M.DahmsInstitute for Materials Research, GKSS Research Centre Geesthacht, Germany F. Pirwitz and M.DahmsInstitute for Materials Research, GKSS Research Centre Geesthacht, Germany This paper reports on design and production of an intermetallic functionally gradient material (FGM), Nb/NbxTiyAlz/TixAlySiz, by using a variant of reactive powder metallurgy. A Nb/NbxTiyAlz/TixAlySiz composite was fabricated with a gradually changing the mixture ratio of the components, from pure Nb metal to intermetallic compositions. The FGM combines ductile Nb-fiber reinforcement and an oxygen resistant TixAlySiz outer coating to improve both the mechanical and environmental properties. The compositionally gradient layers were designed such that the formation of extremely brittle phases was avoided. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 59-64 Tic/Ni3Al FGMの作製：焼結および構造 PREPARATION OF TiC/Ni3Al FGMs: SINTERING AND STRUCTURE L.M.Zhang 1, R.Z.Yuan 1, 大森守2 and 平井敏雄 21 Wuhan University of Technology, Wuhan, P.R.China 2 東北大学　金属材料研究所 L.M.Zhang 1, R.Z.Yuan 1, M.Omori 2 and T.Hirai 21 Wuhan University of Technology, Wuhan, P.R.China 2 Institute for Materials Research, TohoKu University, Japan TiC/Ni3Al composites having different TiC-Ni3Al ratios were prepared by the Hot Pressing process (HP) under 1300 deg.C. Densification of the composite was first investigated. The study indicates an effective improvement of the lower temperature densification by the Cr3C2 addition. Then, the thermo-mechanical properties of the prepared composites were tested and calculated by micromechanical theories. It was shown that for most Ni3Al contents the agreement between the two results is quite good but for some particular contents (40vol% Ni3Al, for instance) the tested results have a significant increase. This phenomenon was discussed and it was attributed to the composites having a "spatial network structure" with particular contents. Finally, fully densified FGMs were fabricated by HP under 1300℃. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 65-70 ステンレス鋼またはZrO2(3Y)傾斜機能材料の作製 PREPARATION OF STAINLESS STEEL/ZrO2(3Y) FUNCTIONALLY GRADIENT MATERIAL 大森守、酒井広隆、大久保昭、平井敏雄東北大学　金属材料研究所　仙台市 M.Omori, H.Sakai, A.Okubo and T.HiraiInstitute for Materials Research, Tohoku University, Sendai, Japan Functionally Gradient Materials (FGM) were prepared from stainless steel and ZrO2(3Y) powder using a spark plasma sintering apparatus. This apparatus is a hot press without a heating element, in which a graphite die is heated with a DC current. The die, with a small diameter at the top and a large diameter at the bottom, creates a temperature gradient between the two sides. The stainless steel/ZrO2(3Y) FGM was prepared by interposing mixed layers in the die. The stainless steel layer was sintered at 1000deg.C and the ZrO2(3Y) at 1200deg.C. The sintered FGM did not contain pores on cracks. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 71-76 ZRO2(3Y)またはNI FGMの作製および特性 PREPARATION AND PROPERTIES OF ZRO2(3Y) /NI FGM 大森守 1, 酒井広隆 1, 平井敏雄 1, 川原正和 2,鴇田正雄 2１．東北大学　金属材料研究所　仙台市２．住友石炭鉱業株式会社　川崎市 M.Omori 1, H.Sakai 1, T.Hirai 1, M.Kawahara 2 and M. Tokita 21 Institute for Materials Research, Tohoku University, Sendai2 Sumitomo Coal Mining, Kawasaki, Japan Functionally gradient materials (FGM) have been prepared from Ni and ZrO2(3Y) powders to raise the heat-resisting ability of metals. A spark plasma sintering apparatus was used to obtain a dense ZrO2(3Y)/Ni FGM. This apparatus is a hot press without heating elements. Graphite dies are heated with a direct current. The die, the upper and lower parts of which have different diameters, creates as temperature gradient. Stacked layers of Ni, ZrO2 and mixed materials were sintered at an optimum temperature between 1000deg.Cand 1200deg.C. None of the layers contained pores or cracks. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 77-82 AlN-M (M=Al, Ni, Mo) システムのナノストラクチャーFGM NANO-STRUCTURED FGM OF THE SYSTEM AlN-M (M = Al, Ni, Mo) 新谷光二北海道大学　札幌市 K.AtarashiyaHokkaido University, Sapporo, JAPAN Nano-structured FGM part of the system AlN-M (M = Al, Ni, Mo, W) were prepared by the method of powder metallurgy. Starting materials, i.e., ultrafine particles were prepared by means of the arc-plasma processing. A compositional gradient mixture of an ultrafine Al particle and an M particle was pressed (200-400 MPa) in a steel die, followed by two-step heating (873K and 1273K) in flowing nitrogen without pressure. The techniques of ultrafine-particle mixing and sintering method with no crystal-grain growth were invented. In this work using an ultrafine particle, the nano-structured FGM part were easily prepared. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 83 窒化アルミニウム系傾斜機能材料の作製 FABRICATION OF AlN-BASED FUNCTIONALLY GRADIENT MATERIAL 曽我部浩一、山川晃、野村俊雄、三宅雅也住友電気工業株式会社　伊丹研究所　兵庫県伊丹市 K. Sogabe, A. Yamakawa, T. Nomura and M. MiyakeItami Research Laboratories Sumitomo Electric Industries, Ltd. Itami, Hyogo, Japan Functionally gradient material (FGM) of tungsten (W) and aluminum nitride (AlN) was fabricated by pressureless sintering. The green compact comprised of eight different composition layers (W: 0.0-30.0wt%) was prepared and sintered in flowing nitrogen. Transmission electron microscopy observation indicates that the W particles are dispersed at AlN grain boundaries and inside of AlN grains. X-ray diffraction pattern shows the W particles do not react with AlN matrix grains. The physical properties of each of the eight layers made with gradually varying W composition have been measured. Some of the physical properties of the AlN-based FGM will be discussed. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 87-94 傾斜機能材料の製造における燃焼合成 SELF-PROPAGATING HIGH-TEMPERATURE SYNTHESIS IN THE PRODUCTION OF FUNCTIONALLY GRADIENT MATERIAL A. G. Merzhanov, A. N. PityulinInstitute of Structural Macrokinetics, Russian Academy of Sciences, Chernogolovka, Russia A. G. Merzhanov and A. N. PityulinInstitute of Structural Macrokinetics, Russian Academy of Sciences, Chernogolovka, Russia High efficiency of self-propagating high-temperature synthesis (SHS) as applied to the production of functionally gradient materials (FGM) has been demonstrated in the studies of Japanese, Russian, Chinese, and American scientists. Essentially three different schemes have been developed so far: 1. A gradient green charge - a gradient material (gradient materials are synthesized from the green charge gradient in its composition). 2. A bi-layer green charge - a gradient material (a gradient structure is formed from the bi-layer green charge with a fused layer controllably impregnating the other to result in product densification). 3. A uniform green charge - a gradient material (a used uniform green charge forms a high-temperature multi-component melt yielding a gradient structure with control over the completeness of phase separation). The former scheme has been proposed by Japanese scientists, the other two have been developed in Russia. Sometimes more complicated schemes are used. - Hard alloys (TiC-Ni, TiB2-Ti, TiB2-Al. TiB2-Cu, and the like), - intermetallics (NiAl, TiNi, TiAl, and the like), - ceramic minerals (a metal or a refractory compound - Al2O3) are among most often produced FGM. In an analytical survey of studies concerning SHS of FGM the problems of SHS mechanisms resulting in the FGM formation have been considered and the influence of physical (mechanical, ultrasonic, electromagnetic) treatment on the structural transformations during SHS synthesis of FGM has been determined. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 95-100 SHS法におけるダイヤモンドを含んだ傾斜機能材料の構造および特性形成の特色 THE PECULIARITIES OF STRUCTURE AND PROPERTIES FORMATION OF DIAMOND-CONTAINING FUNCTIONAL GRADIENT MATERIALS IN THE SHS-REGIME E.LevashovSHS-Center of Moscow Steel and Alloys Institute Moscow, Russia E.LevashovSHS-Center of Moscow Steel and Alloys Institute Moscow, Russia Some peculiarities of diamond-containing FGM manufacturing in the self-propagating high-temperature synthesis (SHS) regime were studied. Because of the short characteristic periods a diamond stays in the high-temperature zone of the combustion wave, it appears possible to produce new materials impregnated with diamond grains by the SHS method without application of high pressure. Conditions were found when diamond preserves its' strength properties in the combustion wave and a new approach to the FGM synthesis allows to raise significantly the limit of exothermic mixture dilution by diamond and to produce a material with a diamond concentration in the layer of up to 50 vol.% . The influence of the mass and composition of the diamond free exothermic mixture layer on the way of structure formation of various SHS FGMs containing diamond was studied. FGM of the systems NiAl/(NiAl+diamond), TiB/(TiB+diamond) were produced. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 101-108 一段階SHS成形における金属強化合金FGMの製造 PRODUCTION OF METAL-HARD ALLOY FGM IN ONE-STAGE SHS COMPACTION A.N.Pityulin, A.E. Sytschev, A.S. Rogachev, and A.G. MerzhanovInstitute of Structural Macrokinetics, Russian Academy of Sciences, Chernogolovka, Russia A.N.Pityulin, A.E. Sytschev, A.S. Rogachev, and A.G. MerzhanovInstitute of Structural Macrokinetics, Russian Academy of Sciences, Chernogolovka, Russia Processes of self-propagating high-temperature (up to 3000deg.C) synthesis (SHS) are known to proceed in powder media as combustion waves at the velocity of 0.1-15.0 cm/s and yield refractory inorganic compounds. Post-SHS compaction of hot products allows the production of poreless cermet alloys of high physico-mechanical characteristics. Combination of large temperature gradients, high temperatures and velocities of the SHS waves makes the process of SHS compaction rather efficient in manufacturing of cermet functionally graded materials (FGM). The present study shows the results of investigations of FGM production in the TiC-Ni, TiB2-Ti, and TiB2-steel systems. Gradient plates (70x70x8 cm) characterized by different types of metal concentration profiles have been synthesized. It has been shown that alloys of symmetric and asymmetric metal distribution over the sample body can be obtained depending on the technological regimes of SHS. When studying the mechanisms of FGM production in SHS compaction, it has been found that impregnation of the porous product with liquid metal is responsible for the formation of concentration profiles with symmetric distribution of metal, while the other case results from the liquid metal migration to the poreless volume of the product. FGMs with asymmetric metal distribution have been shown to form in a one stage process concurrent with its binding to a monolithic metal substrate. Introduction of special additives (getters) to the metal powders has been found to promote the formation of strong poreless intermediate zones of the metal-hard alloy. Alloys with asymmetric metal distribution over the sample body appear to be the most interesting material from the practical viewpoint. They can be successfully used in the manufacturing of articles suffering both abrasive and shock loading, since besides high strength and wear-resistance, they are characterized by high ductility. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 109-114 Al2O3/(または）TiC/Ni/TiC/Al2O3系の対称傾斜機能材料の作製 ELABORATION OF SYMMETRIC FUNCTIONALLY GRADIENT MATERIALS OF THE Al2O3/TiC/Ni/TiC/ Al2O3 SYSTEM 栗振思、谷畑公昭、宮本欽生大阪大学　産業科学研究所　大阪府茨木市 Z.Li, K.Tanihata and Y.MiyamotoInstitute of Scientific and Industrial Research, Osaka University, Ibaraki, Osaka, Japan Symmetric Functionally Gradient Materials of the Al2O3/TiC/Ni/TiC/ Al2O3 and Al2O3-30wt%TiC/TiC/Ni/TiC/30wt%TiC- Al2O3 were fabricated by SHS/HIP. Use of conventional additives such as MgO and Mo2C were useful to control the gradual change of microstructures. Strong compressive residual stress as high as 200-300 MPa was induced in the outer layers due to the compositionally symmetric structures, resulting in remarkable reinforcement of mechanical properties of the outer ceramics. Moreover, new intelligent functions such as flaw tolerance and preferential crack propagation in a safe direction appeared. The symmetric gradient structure can create higher order functions than inherent material properties. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 115-120 プレストレスを与え堅くされた対称傾斜構造を持つAl2O3/Cr3C2/Ni/Al2O3/Cr3C2 PRESTRESS TOUGHENED Al2O3/Cr3C2/Ni/ Al2O3/Cr3C2 WITH SYMMETRIC GRADIENT STRUCTURE 康燕生、宮本欽生大阪大学　茨木市 Y.-S.Kang and Y.MiyamotoOsaka University, Ibaraki, Japan Symmetrically arranged functionally gradient materials in the system Al2O3/Cr3C2/Ni/Cr3C2/Al2O3 were fabricated by SHS/HIP. Owing to the symmetric structure with different thermal expansion rates of the outer Al2O3ceramic and inner Cr3C2-Ni tough layers, a strong compressive residual stress up to 845 MPa was induced in the outer Al2O3 layer, which remarkably reinforced mechanical properties of the Al2O3 ceramics. The hardness and indentation fracture toughness of the Al2O3 reached to 22 GPa and 11 MPa. m1/2, respectively. The flexural strength of the symmetric FGMs was 900 MPa. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 123-128 傾斜機能被膜のためのプラズマ溶射技術 PLASMA SPRAYING TECHNIQUES FOR FUNCTIONAL GRADIENT COATINGS A. Salito、 G.BarbezatSULZER METCO AG Wohlen, Switzerland A. Salito and G.BarbezatSULZER METCO AG Wohlen, Switzerland Plasma spraying coating applications are based on the concept that the substrate provides the shape and strength properties of the component, and the coating provides the necessary interface properties between the component and its environment. Depending on the base material of the component and the environmental characteristics, different coating solutions are possible. Plasma spraying allows the deposition of complex composite materials, such as metal-metal, metal ceramic and ceramic-ceramic, onto functional components. The correct selection of the spray equipment as a significant part of the complete coating cycle is important in order to ensure the reproducibility of the coating properties, especially for coatings mass production. In the field of the fusion technology, thick tungsten and B4C coatings have been developed. The high melting point of tungsten and the low Z value of B4C in relation to the thermomechanical properties makes these materials suitable for use on plasma facing components inside the vessel of a fusion reactor. In the SOFC (Solid Oxide Fuel Cell) domain, the plasma spraying technology allows directly to generate different ceramic and ceramic-metal interlayers of each single cell. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 129-136 残留応力分布および溶射熱遮蔽コーティングのデボンデイングdebonndingした場合の中間層への影響 THE EFFECT OF INTERMEDIATE LAYERS ON RESIDUAL STRESS DISTRIBUTIONS AND DEBONDING OF SPRAYED THERMAL BARRIER COATINGS T.W. Clyne 、Y.C.TsuiDepartment of Materials Science & Metallurgy, University of Cambridge, U.K. T.W. Clyne and Y.C.TsuiDepartment of Materials Science & Metallurgy, University of Cambridge, U.K. Various multi-layer structures have been produced by plasma spraying of NiCrAlY and ZrO2. Residual stress distributions have been established in these systems. Interfacial debonding has been observed to occur as a result of these stresses, with or without applied bending moments. Critical strain energy release rates have thus been measured as ～125, ～20 and ～12 J m-2 for substrate/NiCrAlY, NiCrAlY/ZrO2 and substrate/ZrO2 interfaces respectively. The NiCrAlY "bond coat" between a superalloy substrate and ZrO2 therefore does not, in fact, adhere strongly to the ZrO2. The low stiffness of sprayed ZrO2, which limits the driving force for it to debond, is the key to its good spallation resistance. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 137-142 マグネトロンがスパッタされたAl-Si-Cu皮膜におけるスパッタリング温度の微細構造依存 MICROSTRUCTURAL DEPENDENCE OF SPUTTERING TEMPERATURE IN MAGNETRON-SPUTTERED Al-Si-Cu FILMS M.-K.Liang and Y.-C.LingDepartment of Chemistry, National Tsing Hua University, Hsinchu, Taiwan, Republic of China M.-K.Liang and Y.-C.LingDepartment of Chemistry, National Tsing Hua University, Hsinchu, Taiwan, Republic of China The effects of sputtering temperature and sputtering bias at constant annealing temperature on the sheet resistance, TiO2, and WO3 formation at the Al-Si-Cu/Ti-W interface, and atom diffusion of magnetron-sputtered Al-Si-Cu films were investigated. Statistical methods and microcharacterization techniques were applied to study these effects. A statistical analysis verifies the effect of sputtering temperature on the measured sheet resistance. Samples at sputtering temperature from 20 to 160deg.C are of higher sheet resistance for the formation of interfacial TiO2. Sputtering temperature alone is the dominant factor on the Ti, W, and O atom diffused to Al-Si-Cu layer. Samples at higher sputtering temperature are of higher sheet resistance for the atom diffusion. Secondary ion mass spectrometry (SIMS) analysis of the as-deposited sample depicts the presence of an excess amount of oxygen atoms at the surface, Al-Si-Cu/Ti-W, and Ti-W/Ti interfaces. Rutherfort backscattering spectrometry (RBS) and SIMS analysis reveal the outdiffusion of Ti and W from the Ti-W layer toward the Al-Si-Cu layer. It is concluded that interfacial oxygen reacted with Ti and W to form TiO2 and WO3. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 143-146 傾斜機能材料のMOCVD合成のための金属配位化合物前駆体の設計 DESIGN OF METALS COORDINATION COMPOUNDS PRECURSORS FOR MOCVD SYNTHESIS OF FUNCTIONALLY GRADIENT MATERIALS E.Mazurenko、 A.GrafovInstitute of General and Inorganic Chemistry of the Academy of Sciences of Kiev, Ukraine E.Mazurenko and A.GrafovInstitute of General and Inorganic Chemistry of the Academy of Sciences of Kiev, Ukraine One of the main problems of modern chemistry is the development of fundamental research on chemical compounds structure and bonding correlation, and elaboration on this basis of industrial chemical processes of high efficiency for obtaining of new substances and materials with predetermined properties. The gas-phase processes of metallic, oxide, carbide, nitride, gradient etc. coatings synthesis are among the most promising for thermal-, erosion-, and corrosion protection, synthesis of selective catalysts, functional materials for electronics etc. The main demands are discussed, which are made to Chemical compounds used in CVD synthesis of functional materials. The division of the volatile metals precursors into main classes is given. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 147-151 炭素母体上のZr およびHfオキシカーバイト耐熱コーティングの合成処理の研究 STUDY OF SYNTHESIS PROCESSES OF Zr AND Hf OXYCARBIDE REFRACTORY COATINGS ON CARBON MATRICES A.V.Grafov 1, O.V.Melnik 1, E.A.Mazurenko 1, L.Rizzo 2,P.Gueriero 2, G.A.Battiston 2 and P.Zanella 21 Institute of General and Inorganic Chemistry 2 National Research Council, Ukraine A.V.Grafov 1, O.V.Melnik 1, E.A.Mazurenko 1, L.Rizzo 2,P.Gueriero 2, G.A.Battiston 2 and P.Zanella 21 Institute of General and Inorganic Chemistry 2 National Research Council, Ukraine We have synthesized and studied the thermal decomposition of a series of zirconium and hafnium beta-diketonates, alcoholates and di- pi-cyclopentadienyl-dialcoholates. The fragmentation passways in the vapour phase for all the three types of the precursors are discussed. The optimum conditions for oxide, oxycarbide and carbide phases growth on different carbon matrices are determined. The thermolysis by-products at different process temperatures were characterized by gas-chromatography and mass-spectrometry. The gradient oxycarbide coatings grown were analyzed and characterized microscopically. we are considering such an approach as a chemical way of solution of the functionally gradient materials synthesis problem. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 153-158 異方性多孔セラミック構造のガス相形成 THE GAS-PHASE FORMING OF ANISOTROPIC POROUS CERAMIC STRUCTURES V.Belyakov、 A.PaltchikInstitute General and Inorganic Chemistry of National Academy of Sciences of Ukraine, Ukraine. V.Belyakov and A.PaltchikInstitute General and Inorganic Chemistry of National Academy of Sciences of Ukraine, Ukraine. The possibility of pore structure modification for oxide based ceramic material by chemical reactions in the gas phase has been studied. The change of alumina-zirconia ceramic structure was studied as result of gas phase pyrolysis of organic compounds, including possible reactions of oxidation, reduction and carbide's formation. The change of pore structure in the range from 1 to 100 nm by using of these reactions in different combinations was found. As is shown, optimal experimental conditions provide possibilities to forming pore structure in the volume or on the surface. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 161-166 沈降によるセラミック‐金属傾斜機能材料 CERAMIC-METAL FUNCTIONAL GRADIENT MATERIALS BY SEDIMENTATION T.Jungling, J.Brombach and B.KiebackFraunhofer-Institute for Applied Materials Research, Dresden, Germany T.Jungling, J.Brombach and B.KiebackFraunhofer-Institute for Applied Materials Research, Dresden, Germany Sedimentation is a suitable method for the deposition of gradient structures with plane geometry and could be an economic way to manufacture tiles. The gradient itself can be adjusted in a wide range by the particle size and the size distribution of the components, the viscosity of the sedimentation liquid and the powder to liquid ratio. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 167-172 連続鋳込み成形によって得られた、Y‐TZP/Al2O3傾斜機能セラミックスの機械的特性 MECHANICAL PROPERTIES OF Y-TZP/Al2O3 FUNCTIONALLY GRADED CERAMICS OBTAINED BY SEQUENTIAL SLIP CASTING A.J.S㌻chez-Herencia 1, J.S.Moya 1 and J.Llorca 21 Instituto de Cer㍊ica y Vidrio (CSIC)2 Departamento de Ciencia de Materiales. Universidad Polit残nica de Madrid, Madrid Spain A.J.S㌻chez-Herencia 1, J.S.Moya 1 and J.Llorca 21 Instituto de Cer㍊ica y Vidrio (CSIC)2 Departamento de Ciencia de Materiales. Universidad Polit残nica de Madrid, Madrid Spain Using sequential slip casting technique, Al2O3/Y-TZP layered and close to theoretical density Functionally Gradient Ceramic (FGC) has been obtained. Taking into account the thermal expansion coefficient (alpha) and Young's modulus (E) of each layer the thermal stress distribution within the FGC was determined by the Finite Element Method (FEM). The bending stress has been determined with either the alumina layer or the Y-TZP layer under tension. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 173-178 二成分粒子混合のろ過機構の使用による、傾斜複合材料の形成 FORMATION OF GRADIENT COMPOSITES BY USING THE FILTRATION MECHANISM OF BINARY PARTICULATE MIXTURE 森英利、桜井幸夫、中村正秋、外山茂樹名古屋大学　化学工学科 H.Mori, Y.Sakurai, M.Nakamura and S.ToyamaDepartment of Chemical Engineering, Nagoya University, Japan Formation process of smoothly graded composite was studied to provide a fundamental idea for manufacturing FGM, in which process a particulate mixture of two kinds of slurry was filtered semi-batchwise. The experiment using particulate slurries of nickel and alumina proved that the gradient was easily controlled by changing the mixing mode of two slurries. The formation process of gradient composite was successively predicted with a theory of cake filtration which allowed the design of the optimal gradients. The filtration process was also applied to prepare a porous material with a continuous porosity profile. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 179-184 炭素発泡体の直接電気化学的酸化を伴う傾斜材料の製造 PROCESSING OF GRADIENT MATERIALS WITH DIRECTED ELECTROCHEMICAL OXIDATION OF CARBON FOAMS O.Guthmann 1, A.Reller 2, B.Kastening 3, and J.Rodel 41 TU Hamburg-Harburg 2, 3 University of Hamburg 4 TH Darmstadt, FG Nichtmetallisch Anorganische Werkstoffe, Germany O.Guthmann 1, A.Reller 2, B.Kastening 3, and J.Rodel 41 TU Hamburg-Harburg 2, 3 University of Hamburg 4 TH Darmstadt, FG Nichtmetallisch Anorganische Werkstoffe, Germany A new method to generate three - dimensional, step-less gradient materials is presented. It is based on electrolytic dissociation of an electrically conducting porous preform. The porous preform - in our case porous carbon - is placed in an electrolyte of an electrical conductivity in the same range of the preform. Depending on local electrical potential in the preform, position - dependent dissociation and anodic oxidation of carbon to carbon dioxide will take place. This graded preform can then be used in several ways to produce the final gradient material. 1. The preform is taken as the gradient material itself. 2. The preform is infiltrated with a second phase. 3. The second phase is e.g. sintered and the carbon burnt out. 4. The cavities which were originally occupied by carbon are now infiltrated. In this presentation we will focus on the dissociation process and characterize the influence of ratio of electrical conductivity of preform to electrolyte. Depending on ratio, thinning takes place either close to the anode or away from the anode. Results are presented in terms of density distributions of carbon ligament sizes. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 185-190 温度差異熱処理の方法による、傾斜機能鋳材料の開発 DEVELOPMENT OF FUNCTIONALLY GRADIENT CAST MATERIAL BY MEANS OF TEMPERATURE DIFFERENCE HEAT TREATMENT 多田周二、高橋利夫、阿部利彦東北工業技術研究所　仙台市 S.Tada, T.Takahashi and T.AbeTohoku National Industrial Research Institute, Sendai, JAPAN We have developed functionally gradient cast material by means of temperature difference heat treatment. Although the austempering of spheroidal graphite ductile cast iron is able to produce ADI (Austempered Ductile Iron) with excellent mechanical properties, this treatment enables improvement only in tensile strength or toughness, and enhances one to the detriment of the other. However, by means of an imposed temperature difference, austempering results in the production of a new type of ADI, known as FGADI, which possesses functionally gradient mechanical properties. As a result of temperature difference austempering, the mechanical properties of FGADI vary along the direction corresponding to the temperature gradient. Because of this mechanical property gradient, FGADI shows an interesting bending behaviour whose fatigue life depends strongly on the loading direction. Also, it is clear that the compressive property in a ring specimen must be improved by applying a negative temperature gradient in its radial direction. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 191-196 傾斜機能吸着剤としての、新しい無機イオン交換体の非-伝統的使用 NON-TRADITIONAL USE OF NEW INORGANIC ION-EXCHANGERS AS FUNCTIONALLY GRADED SORBENTS I.Grafova 1, A.Bortun 1, S.Khainakov 1 and P.Gueriero 21 Institute of Sorption and Endoecology Problems of the National Academy of Sciences of Ukraine, Kiev, Ukraine2 Institute of Chemistry, Inorganic Technologies and Advanced Materials, National Research Council of Italy, Padua, Italy I.Grafova 1, A.Bortun 1, S.Khainakov 1 and P.Gueriero 21 Institute of Sorption and Endoecology Problems of the National Academy of Sciences of Ukraine, Kiev, Ukraine2 Institute of Chemistry, Inorganic Technologies and Advanced Materials, National Research Council of Italy, Padua, Italy Currently all over the world, a wide spectrum of organic and inorganic ion-exchangers is used for various water treatment processes and water solution purification. To a somewhat lower extent, the ion-exchangers are used in organic media, while hitherto the examples of their use in absolutely non-aqueous non-polar media are quite rare. It is connected with both a traditional approach to ion-exchangers, as materials, which are carrying out their functionality under a condition of ion dissociation in the ion-exchange sorbent macromolecule, and also with the impossibility of complete elimination of the structural water from the sorbent's granule. One would think that this creates a risk for water penetration into the non-aqueous medium. That way, the gradient of structure and composition is created within the sorbent's granule. This effect enables us to use such sorbents in an absolutely organic media. Polymeric titanium and zirconium phosphates were used for ultra-purification of some organoindium precursors from impurities of the compounds of other metals. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 197 密度勾配を伴う組成物質のための、中空-球構造 HOLLOW-SPHERE STRUCTURES FOR COMPONENTS WITH DENSITY GRADIENTS H.Kubsch and B.KiebackFraunhofer-Institute for Applied Materials, Dresden, Germany H.Kubsch and B.KiebackFraunhofer-Institute for Applied Materials, Dresden, Germany In many areas of application, the use of materials having low density combined with heat resistance, strength, toughness and other properties is interesting. However, in many cases such combinations cannot be established just by employing light metals. An alternative, innovative possibility consists in making materials, semi-finished stock, or components by using metallic hollow spheres. These have to be stacked and connected in such a way as to ensure the formation of a 3D aggregate in the form of a load-bearing solid network with regularly dispersed pores of equal or different size. By this way, it is possible to vary within wide limits the average density of the material; at the same time, it is possible to adapt the properties to the expected load profile under service conditions, e.g. heat resistance, by means of judicious selection of the base material for the hollow spheres. In the ideal case, solid state matter will be placed, within these lightweight materials, only at those locations where their presence is essential for obtaining the properties in demand. Thus, new principles of "building" the material are suggested using gradients of pore diameter as well as of local pore fraction. Experimental results concerning the fabrication and properties of the hollow spheres will be reported, as well as FE calculations concerning the deformation behaviour. As an example, multilayer plates, composed of hollow spheres with different size, but with dense surface layers, will be treated. As main advantage of the well-defined pore-size distribution of these materials emerge the compatibility and the statistical reliability of high-porosity materials. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 201-207 不均一化方法に基づく、傾斜機能材料の応力解析 STRESS ANALYSIS OF FUNCTIONALLY GRADIENT MATERIALS BASED ON A HETEROGENIZATION PROCEDURE E.Honein 1 T.Honein 2 and G.Herrmann 11 Division of Applied Mechanics, Stanford University, Stanford2 General Science and Technology, Inc., Sunnyvale, USA E.Honein 1 T.Honein 2 and G.Herrmann 11 Division of Applied Mechanics, Stanford University, Stanford2 General Science and Technology, Inc., Sunnyvale, USA In this paper, we consider an element of a composite material, consisting of a matrix which contains a cylindrical fiber whose material properties vary continuously in the radial direction. The system is subjected to arbitrary loadings, which however, induce only antiplane deformation. This problem of elastostatics is treated by employing the methodology of heterogenization developed by the authors. It will be shown that when the loading is uniform, the functionally gradient fiber could be replaced by a homogeneous fiber without affecting the stress field in the matrix. However, the stress field in the fiber is very dependent on the material properties of the system. These can be selected to eliminate the elastic mismatch between fiber and matrix and thus reduce the stress amplification at the interface. A simple example illustrating how heterogeneous materials can be employed to reduce stress concentration around holes is given. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 209-214 傾斜セラミック-金属構造中での残留応力の特性評価：回折実験とFEM計算の比較 CHARACTERIZATION OF RESIDUAL STRESSES IN GRADED CERAMIC-METAL STRUCTURES: A COMPARISON OF DIFFRACTION EXPERIMENTS AND FEM CALCULATIONS B.H.Rabin 1, R.L.Williamson 1, T.R.Watkins 2, X.-L.Wang 2, C.R.Hubbard 2 and S.Spooner 21 Idaho National Engineering Laboratory Idaho Falls, Idaho, 2 Oak Ridge National Laboratory Oak Ridge, TN, USA B.H.Rabin 1, R.L.Williamson 1, T.R.Watkins 2, X.-L.Wang 2, C.R.Hubbard 2 and S.Spooner 21 Idaho National Engineering Laboratory Idaho Falls, Idaho, 2 Oak Ridge National Laboratory Oak Ridge, TN, USA The residual stress state in a graded ceramic-metal structure has been studied using a combination of experimental and numerical techniques. Al2O3-Ni was examined as a model materials system, and axisymmetric graded composite structures were fabricated by a powder processing method involving consolidation of layered green compacts. Residual strain distributions were experimentally measured along the surface and within the interior of the specimen using x-ray and neutron diffraction techniques, respectively. The experimental results were compared with predictions from finite element method (FEM) calculations of the residual strain and stress distributions made using a temperature-dependent elastic-plastic model of the specimen. Several important features of the predicted stress distribution were qualitatively verified by the experimental results, however, quantitative agreement between the calculated and measured peak stress values was not obtained. In this paper, details of the experimental methods are described, and possible explanations for the lack of agreement between the experimental and modeling results are discussed. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 215-221 連結したセラミック-金属構造中の残留応力：中間層およびクリープ効果のFEM研究 RESIDUAL STRESSES IN JOINED CERAMIC-METAL STRUCTURES: FEM STUDIES OF INTERLAYER AND CREEP EFFECTS R.L.Williamson, B.H.Rabin, and G.ByerlyIdaho National Engineering Laboratory Idaho Falls, Idaho, USA R.L.Williamson, B.H.Rabin, and G.ByerlyIdaho National Engineering Laboratory Idaho Falls, Idaho, USA In recent studies, elastic plastic finite element models (FEM) have been developed to investigate the residual stress state within graded ceramic-metal structures during cooling. The graded interlayer region was approximated as a series of perfectly bonded layers, each having slightly different material properties. A variety of geometries and material systems have been studied. In combination with experimental measurements, these models have provided significant insight into the understanding of residual stress and strain states within graded structures and have assisted in graded specimen fabrication activities. In this study, the elastic-plastic FEM models are expanded to include transient thermal behavior, permitting prediction of the coupled thermomechanical response of graded specimens. Additionally, a creep constitutive law is included to account for time dependent deformation at elevated temperatures. An axisymmetric cylindrical specimen consisting of a nickel substrate, a graded composite Al2O3-Ni interlayer, and an Al2O3 coating is used to approximate a thermal barrier application. Simple rule-of-mixture techniques, coupled with experimental measurements, are employed to establish constitutive laws for the composite interlayer materials. The model is used to investigate stress and strain distributions within the graded specimen during thermal loading. The effects of thermal gradients and the relative importance of elastic-plastic and creep deformation are described. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 223-228 鋭界面　対　傾斜機能金属-セラミック積層：機械的応答性のための幾何構造最適化 SHARP INTERFACES VERSUS FUNCTIONALLY GRADED METAL-CERAMIC LAYERS: GEOMETRICAL OPTIMIZATION FOR MECHANICAL RESPONSE M.Finot 1, S.Suresh 1 and A.E.Giannakopoulos 21 Massachusetts Institute of Technology, Cambridge, MA USA2 The Royal Institute of Technology, Stockholm, Sweden M.Finot 1, S.Suresh 1 and A.E.Giannakopoulos 21 Massachusetts Institute of Technology, Cambridge, MA USA2 The Royal Institute of Technology, Stockholm, Sweden Analytical models, detailed finite-element analyses and experiments on model systems are used to develop mechanism maps, geometrical optimization and guidelines for materials selection for a variety of layered materials with sharp interfaces and compositional gradients. Conditions under which compositional gradients are beneficial or detrimental for a number of different geometries of the FGM will be identified. Experimentally based constitutive formulations will be used to identify critical temperature limits for a wide range of metal-ceramic systems within which distinctly different patterns of thermal residual stresses, monatomic and cyclic plastic zones and corner singularities evolve. Specific numerical examples in several different model material systems will be presented to illustrate optimal combinations of geometrical design and compositional gradation. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 229-234 Ni-Al2O3傾斜材料の熱サイクリングの実験的研究 EXPERIMENTAL STUDIES OF THERMAL CYCLING OF A Ni-Al2O3 GRADED MATERIAL M.Finot 1, S.Suresh 1, C.Bull 2, A.E.Giannakopoulos 3, M.Olsson 3 and S.Sampath 41 Massachusetts Institute of Technology, Cambridge MA2 Brown University, Providence RI, USA 3 Royal Institute of Technology, Stockholm, Sweden 4 State University of New York at Stony Brook, NY, USA M.Finot 1, S.Suresh 1, C.Bull 2, A.E.Giannakopoulos 3, M.Olsson 3 and S.Sampath 41 Massachusetts Institute of Technology, Cambridge MA2 Brown University, Providence RI, USA 3 Royal Institute of Technology, Stockholm, Sweden 4 State University of New York at Stony Brook, NY, USA In this presentation, we will discuss numerical and experimental results on the elasto-plastic deformation of a functionally graded metal/ceramic system subjected to cyclic variations in temperature. To begin with, closed-form solutions will be presented, as functions of the thermomechanical properties and the geometry of the system, for the evolution of residual stresses and plastic yielding. The numerical simulations of thermal cycling will then specifically focus on an Al2O3-Ni FGM system where the evolution of stress-strain hysteresis and cyclic plasticity, including that initiating at sharp edges, is modeled. Systematic experiments which deal with the measurement of constitutive response for different mixtures of the two phases are used to guide the numerical model. The influence of variations in physical and mechanical properties of the constituent phases with temperature on thermally-induced deformation will also be described. Critical issues for fundamental and scientific research will be highlighted. Controlled experiments of the influence of thermal cycling on microstructural stability, chemical reactions and diffusion in the Ni-Al2O3 model system will also be discussed. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 235-240 突然に加熱したセラミック-金属傾斜材料の弾塑性応答性での結合した熱力学モデル A COUPLED THERMAL-MECHANICAL MODEL ON ELASTIC-PLASTIC RESPONSE OF SUDDENLY HEATED CERAMIC-METAL GRADIENT MATERIALS Q.-J.Zhang, G.-H.Zhang and R.-Z.YuanWuhan University of Technology, Wuhan, P. R. China Q.-J.Zhang, G.-H.Zhang and R.-Z.YuanWuhan University of Technology, Wuhan, P. R. China A coupled thermal-mechanical model on the elastic-plastic response of suddenly heated ceramic-metal gradient materials is proposed. The model is intended to demonstrate the importance of the coupling effect between the heat conduction and the plastic deformation in the dynamic case. The mathematical description for the model is established first, which leads to a highly nonlinear heat conduction equation containing the plastic deformation effect. A newly-developed plastic theory of particle-reinforced composites [1] is used to estimate the inelastic stress-strain relationship in the graded layers. The mathematical description is solved for different thermal conditions on the bottom metal side boundary; the temperature and stress responses are then obtained. The coupling effect is found to be strongly dependent on the bottom thermal condition: if the bottom is insulated, the effect is significant; if the bottom is cooled by flowing liquid nitrogen with a large heat transfer coefficient, the effect is not appreciable. Between the two limiting cases, the coupling effect increases as the cooling decreases. English 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 3rd Internattional Symposium on Structural and Functional Gradient MaterialsFGM'94PROCEEDINGS 8 1994-12-31 241-246 微細機構アプローチのC/M　FGMのマクロ弾塑性応答性への影響　パート1：定常状態問題 INFLUENCE OF MICROMECHANICAL APPROACHES ON MACRO ELASTIC-PLASTIC RESPONSE OF C/M FGMs PART l: STEADY- STATE PROBLEM J.-H.Wang, Q.-J.Zhang and R.-Z.YuanWuhan University of Technology, Wuhan, P. R. China J.-H.Wang, Q.-J.Zhang and R.-Z.YuanWuhan University of Technology, Wuhan, P. R. China The influence of different micromechanical approaches on the macro elastic-plastic response of ceramic/metal FGMs in a steady-state is studied. Three popular micromechanical approaches, the rule of mixture, mean-field micromechanics (MFM) and self-consistent micromechanics (SCM), are first applied to predict the effective properties of a Al2O3/Ni FGM. Then, based on the predicted properties, the macro response, including the elastic stress, elastic-plastic stress and the optimum compositional profile, is analyzed and the influence of the three different approaches is systematically compared. The investigation shows that: (1) the results obtained from the MFM and SCM are quite similar, but the those obtained from the rule of mixture are different; (2) the elastic-plastic response is more sensitive to the micromechanical approaches than the elastic response. Consequently, selecting an appropriate micromechanical approach to predict FGM, the effective properties are important for the materials design. English