使用热力学处理稳定Zn-Cu-Mn-Mg合金的流应力
Morteza S Ardakani1, S L Kampe1, Jaroslaw W Drelich1
1Department of Materials Science and Engineering, Michigan Technological University, Houghton, MI 49931, USA.
概括
这项研究改进了用于承载应用的合金,通过减少应变软化和通过回火的速率灵敏度. 优化二级阶段和粒度大小提高了它们适用于可生物吸收的金属设备的适用性.
科学领域:
- 材料科学 材料科学 材料科学
- 生物材料工程 生物材料工程
- 金工业是一种金工业.
背景情况:
- 基于的合金为可生物吸收的金属设备提供了有希望的生物相容性和腐蚀率.
- 对于负载应用的应变软化和应变速率灵敏度的管理仍然存在挑战.
研究的目的:
- 为了制定和描述新的Zn-Cu-Mn-Mg合金.
- 调查回火对机械性能的影响,特别是应变软化和应变速率灵敏度.
- 了解拉伸试验期间的微结构演变及其与合金行为的关系.
主要方法:
- 三种Zn-xCu-yMn-0.05Mg合金的配制,含有不同Cu和Mn的含量.
- 在未制状态下微观结构和拉伸性能的表征.
- 在320°C进行回火处理,以评估其对应变软化和应变速率灵敏性的影响.
- 在室温拉伸试验期间进行微结构分析,以确定动态再结晶等机制.
主要成果:
- 在320°C的火中抑制了应变软化和应变速率的敏感性,这是由于二级阶段溶解和粒度粗.
- 动态再结晶被确定为拉伸测试期间应变软化的主要机制.
- 合金表现出高达200°C的良好热稳定性,持续60小时,MnZn13沉物固定在粒度边界.
- 合金不易受到自然老化的影响.
结论:
- 在Zn-Cu-Mn-Mg合金中,应变软化和速率敏感性可以通过受控的回火和微结构调整来减轻.
- 优化二次相分数和颗粒大小对于消除动态再结晶和提高承载能力至关重要.
- 这些发现增强了合金在先进的可生物吸收金属设备中的潜力.
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