Dislocation theory model for local deformation behavior in bcc metal through TEM in-situ straining technique

2017 Fiscal Year Final Research Report

• Project/Area Number: 15H04149
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Structural/Functional materials
• Research Institution: National Institute for Materials Science
• Principal Investigator: Ohmura Takahito 国立研究開発法人物質・材料研究機構, 構造材料研究拠点, 副拠点長 (40343884)
• Co-Investigator(Kenkyū-buntansha): 井 誠一郎 国立研究開発法人物質・材料研究機構, 構造材料研究拠点, 主幹研究員 (60435146) ; 関戸 信彰 国立研究開発法人物質・材料研究機構, 構造材料研究拠点, 主任研究員 (10462516)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: Fe基合金 / 転位 / 粒界 / 結晶粒径 / ナノインデンテーション

Outline of Final Research Achievements

TEM in-situ straining measurements for Fe base alloys revealed that dislocations disappear at the grain boundary during deformation, which is not consistent with conventional of pile-up model. In the case of a steel containing carbon with fine microstructures, strain burst is retard due to a high resistance to dislocation motion. The fine structure causes low dislocation mobility and depresses a dislocation multiplication leading to a planar dislocation structure. The size of plastic zone underneath the indenter induced by ex-situ indentation is smaller for Fe-Si alloy that that of IF steel.

Free Research Field

材料強度物性