在PHF工艺下,Al-Li合金的机械性能和微观结构演变
Zhiang Gong1,2,3,4, Xiang Huang1,2,3,4, Peiliao Wang1,2,3
1Hubei Key Laboratory of Advanced Technology for Automotive Components, Wuhan University of Technology, Wuhan 430070, China.
Materials (Basel, Switzerland)
|February 13, 2025
概括
一个新的预应变和预老化硬化热成型 (PHF) 工艺优化了Al-Li合金. 这种方法缩短了处理周期,提高了航空航天应用的机械性能.
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.
- 航空航天工程 航空航天工程
背景情况:
- - (Al-Li) 合金由于其优越的机械性能,在航空航天领域至关重要.
- 传统的热力学处理Al-Li合金是漫长的,需要优化.
- 开发高效的加工方法对于推进Al-Li合金应用至关重要.
研究的目的:
- 为Al-Li合金引入和评估一种新的预应变和预老化硬化热成型 (PHF) 工艺.
- 调查前应变,前老化和热成型参数对微观结构和机械性能的影响.
- 为Al-Li合金建立一个更短,更有效的热力学处理周期.
主要方法:
- 实施一个多阶段的工艺,包括预应变,预老化和热成型.
- 通过控制的工艺阶段对多相沉和相变的宏观控制.
- 微结构分析以观察相位演变,特别是T1, δ'和 θ'相位.
- 拉力和屈服强度测试,以评估机械性能.
主要成果:
- 对2A97 Al-Li合金的最佳PHF工艺参数被确定为7%的预应变,80°C/16小时的预老化和250°C/10分钟的热成型.
- 这种特定的工艺产生了最优的拉力强度和565.3MPa和531.2MPa的产量强度.
- 预菌株促进了T1相核和动态再结晶,而10分钟的保温时间确保了细,均的T1沉物.
结论:
- 拟议的PHF工艺有效地改进了Al-Li合金的微观结构并提高了其机械强度.
- 预应变在促进热形成过程中有利的相位转换和再结晶方面发挥着关键作用.
- 这种创新的短过程成型方法比传统的长时间热力学处理对Al-Li合金提供了显著的优势.
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