Challenge to Managing Both Strength and Ductility in Metallic Materials

2014 Fiscal Year Final Research Report

• Project/Area Number: 24246114
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Structural/Functional materials
• Research Institution: Kyoto University
• Principal Investigator: TSUJI Nobuhiro 京都大学, 工学(系)研究科(研究院), 教授 (30263213)
• Co-Investigator(Kenkyū-buntansha): TERADA Daisuke 千葉工業大学, 大学院工学研究科, 准教授 (80432524) ; SHIBATA Akinobu 京都大学, 大学院工学研究科, 准教授 (60451994)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 金属材料 / 組織制御 / 強度 / 延性 / 靭性 / 結晶粒 / 粒界 / 塑性不安定

Outline of Final Research Achievements

Important and fundamental results were acquired for managing both high strength and large ductility in metallic materials. In most cases, the tensile ductility of metals is determined by plastic instability, so that enhancing strain-hardening ability is primarily important. The structures dispersing fine precipitates and particles are effective to manage strength and ductility especially in non-ferrous metals having no phase transformation of matrix. However, the enhancement of strain-hardening by this method is limited, since precipitation hardening firstly increases yield strength. It has been found that dual phase microstructures composed of hard phase and soft phase are quite important for managing both strength and ductility. So-called bi-modal structures did not enhance the strain-hardening capability of the material.

Free Research Field

金属材料学、材料強度学、材料組織学