Download file (3.15MB)
Download as zip (2.93MB)

コレクション

引用

説明:

Low-carbon dual-phase (DP) steels, composed of a soft ferrite phase and a hard martensite phase, are known as promising advanced high-strength steels (AHSSs) due to their high strength and good ductility at low fabrication cost. However, the deformation behavior of DP steels is still not fully understood because of their complex mixed-phase distribution and mechanical interactions between two phases during deformation. The present study quantitatively investigated the effect of martensite distribution on mechanical properties and local deformation-fracture behavior, using the digital image correlation (DIC) technique. Two types of DP structures were prepared: one with a chained martensite distribution (chained DP) and one with an isolated martensite distribution (isolated DP). The chained DP specimen exhibited a superior tensile property, achieving both high strength and large ductility compared to the isolated DP specimen. DIC strain analysis revealed that the chained DP structure showed relatively homogeneous deformation due to the greater contribution of martensite to plastic deformation. In contrast, the isolated DP specimen experienced significant strain localization in the soft ferrite grains. Despite high global strains, non-plastically deformed zones were observed in the central regions of large, isolated martensite particles. Notable differences in micro-void evolution were also observed between the two specimens. The chained DP specimen had a large number of randomly distributed micro-voids, ranging from 0.5 μm to 2 μm in size. In contrast, the isolated DP specimen contained fewer micro-voids, with some aligned at an angle of ~65° to the tensile direction, potentially leading to early tensile fracture.

権利情報:

• Creative Commons BY-NC-ND Attribution-NonCommercial-NoDerivs 4.0 International
  

  © 2024. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/

キーワード: dual-phase steel, mechanical properties, digital image correlation (DIC), strain distribution, martensite morphology, micro-void

刊行年月日: 2024-10-24

出版者: Elsevier BV

掲載誌:

• Materials Science and Engineering: A (ISSN: 09215093) vol. 918 147445

研究助成金:

• Core Research for Evolutional Science and Technology
• Japan Society for the Promotion of Science

原稿種別: 著者最終稿 (Accepted manuscript)

MDR DOI: https://doi.org/10.48505/nims.5067

公開URL: https://doi.org/10.1016/j.msea.2024.147445

関連資料:

その他の識別子:

連絡先:

更新時刻: 2024-12-02 11:36:25 +0900

MDRでの公開時刻: 2026-10-24 08:28:56 +0900