# Fileset

[GrandMeeting_Abstract_VASYLKIV O.pdf](https://mdr.nims.go.jp/filesets/538f688f-84b7-469c-b540-6f04476b2546/download)

## Creator

[VASYLKIV Oleg](https://orcid.org/0000-0002-5041-6130)

## Rights

[In Copyright](http://rightsstatements.org/vocab/InC/1.0/)

## Other metadata

[Deformation-resistant UHTC composites with superior hardness, toughness, and flexural strength up to 2000°C](https://mdr.nims.go.jp/datasets/fe89852e-3a93-4906-ab87-4dce8ef264cd)

## Fulltext

第11回日本MRS学術シンポジウム実行委員会（4/17）の議事進行と議題MRM2023/IUMRS-ICA2023 Grand Meeting December 11-16, 2023, Kyoto, Japan  MRS-Japan   Fig. 1. Effect of temperature on the strain-stress relation in monolithic boron carbide. (a) shows the typical strain-stress curves at 1600 °C & 2000 °C. (b) shows the flexural strength as a function of the temperature and total strain accumulated during the test at a 0.5mm/min rate. (c) bulk ceramic sample deformed at 2000 °C.  [Abstract Guideline (Leave two lines for presentation number)]  Deformation-resistant UHTC composites with superior hardness, toughness, and flexural strength up to 2000°C   *Vasylkiv Oleg  National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki, 305-0047, Japan  *oleg.vasylkiv@nims.go.jp  Keywords: UHTC, SPS, strength, hardness, toughness, deformation resistance  The request for new multipurpose deformation-resistant ultra-high temperature ceramics (UHTC), able to act as special engine and vehicle protection, ceramic segmented leading edge components for aerospace, plasma-facing, ceramic parts for solar towers used for gas turbine operation in a combine cycle power plants (grids, superheaters, reheaters, evaporators, stream turbines, condensers, and chimneys) cause the worldwide demand in a new class of ceramic composites of incredible high strength, sufficient balance between high toughness & hardness.  Confirmed room to ultrahigh temperature deformation resistivity of reaction-driven SPSed (RD-SPS) boron carbide, TiB2 with stiff skeleton of B4C, Zr-Ta boride composite with artificially created hierarchical superstructure, TaB, and high-entropy TaB2-ZrB2-TiB2-HfB2 to be addressed. Mechanism of ultra-high temperature flexure & strain driven amorphization in polycrystalline boron carbide been analyzed. With RT to 1800 °C mean strength of 650 MPa, B4C exhibits ultrahigh flexural strength far exceeding 1000 MPa accompanied by change in the deformation mechanism from brittle fracture to plastic deformation at 2000 °C. STEM observations revealed that the amorphization is of microstructural origin for the observed plasticity in B4C at 2000 °C. Depending on loading rate B4C ceramic showed 1000 - 8400 MPa strength with plastic stress-strain curve (Fig. 1). Even rapid deformation in elastic manner at 25 mm/min was resulted in mean strength 675 MPa - same as for RT, confirming its deformation resistivity (Scripta Materialia 210 15 Mar (2022) 114487).   RD-SPSed TiB-B4C exhibits mean flexural strength of 1000 MPa for up to 1800 °С (Scientific Report, 13 (2023) 6915) with further increasing to 1760 MPa at 2000 °C. Same as above, the ultrahard, tough, deformation resistant Ta monoboride (Scripta Materialia 229 May (2023) 115383), Zr-Ta multiboride (J. Am. Ceram. Soc., 105 [11] Nov. (2022) 6989-7002), Zr-Ta-Nb diboride (Scripta Materialia 225 1 Mar (2023) 115170), and high-entropy TaB2-ZrB2-TiB2-HfB2 with an average flexural strength of 400 MPa of up to 2000 °С are the new multipurpose deformation-resistant ceramics with wide range of possible applications. (c)