通过稳定阶段边界缓解应变局部化,以加强多主元素合金
Jinliang Du1,2,3, Shukuan Guo4, Hangqi Feng1
1School of Naval Architecture, Ocean and Energy Power Engineering, Wuhan University of Technology, Wuhan, 430063, P. R. China.
Advanced science (Weinheim, Baden-Wurttemberg, Germany)
|March 8, 2025
概括
研究人员开发了一种新的生物灵感合金,通过整合纳米尺度的身体中心立方 (BCC) 和面部中心立方 (FCC) 阶段. 这种多主元素合金 (MPEA) 在不需要热处理的情况下实现了超高强度和柔性,克服了传统的限制.
科学领域:
- 材料科学 材料科学 材料科学
- 金工业是一种金工业.
- 机械工程 机械工程
背景情况:
- 多主元素合金 (MPEA) 为增材制造提供了稳定性,但遭受了应变局部化,限制了它们的机械性能.
- 传统的增强性的策略往往侧重于抑制高能点或在裂尖端分散能量,很少实现这两者.
研究的目的:
- 引入纳米尺度的身体中心立方体 (BCC) 和面部中心立方体 (FCC) 阶段到MPEA中,灵感来自小鼠膜.
- 通过生物启发的微观结构设计,通过减轻菌株局部化来增强MPEA的性和强度.
主要方法:
- 在MPEA中纳入纳米级BCC和FCC阶段,在阶段边界稳定.
- 使用原子计算来研究跨阶段的位移转移机制.
- 机械性能的表征,包括拉伸强度和柔性.
主要成果:
- 在不经热处理的情况下,实现了超高的抗拉强度 (≈1458.1 MPa) 和柔性 (≈21.2%) .
- 证明了协同的硬化机制,包括裂偏移,阻塞和桥梁.
- 原子计算揭示了部分原子平面迁移,驱动着相间连续的位移转移.
结论:
- 生物灵感MPEA设计克服了纳米级合金的局部硬化限制.
- 发现了MPEA的基本机械机制,进步了对超强,柔性材料的理解.
- 这种方法为设计用于苛刻应用的高性能合金提供了新的途径.
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