通过在裂前面进行大规模的位移吸收来提高性
Jiazhi Zhang1, Qin Yu2, Jiazhuang Tian1
1Department of Advanced Optical and Microelectronic Equipment, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China.
概括
研究人员发现,在新型钢中,脱位被吸收到奥氏体中,防止裂并克服强度-柔性权衡. 这导致了具有优越强度,柔性和性的经济有效的钢.
科学领域:
- 材料科学 材料科学 材料科学
- 金工业是金工业的一个方面.
- 机械工程 机械工程
背景情况:
- 为了获得高性能结构材料,由于局部应力和有限的位移移动性,经常面临强度-柔性/性的权衡.
- 开发低成本,高性能材料仍然是现代工程的一个关键挑战.
研究的目的:
- 为了研究异质钢在裂纹前线的异常脱位行为.
- 通过克服强度-柔性权衡来探索一种提高材料性能的新机制.
主要方法:
- 制造一个不均的钢,包括炼的拉斯马石和碳丰富的保留奥氏体.
- 微结构分析,观察裂前线的脱位行为.
- 机械测试用于评估强度,柔性和断裂性.
主要成果:
- 观察到裂前面的排位吸收,与典型的排位排放形成鲜明对比.
- 证明奥氏体吸收马氏体的脱位,减轻应力度和减缓裂传播.
- 取得了卓越的性能:强度延长系数>50 GPa·%和断裂性>130 MPa·m1/2.
结论:
- 一种基于位吸收到保留的奥氏体的新型硬化策略是有效的.
- 这种机制使得能够开发出具有超高强度,性和性,具有成本效益的普通钢.
- 这些发现为钢铁行业的先进发展提供了一个有希望的途径.
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