王圣楠,刘满平,陈健,王晓芬,薛周磊

• 1:江苏大学材料科学与工程学院

摘要(Abstract)：

利用X射线衍射仪、透射电镜和硬度测试研究了Mg含量对Al-Mg铝合金高压扭转(HPT)及不同温度退火30 min后的微观结构和硬度的影响。结果表明:随Mg含量从0 mass%增加到5.0 mass%,HPT后Al-Mg铝合金的平均晶粒尺寸明显减少、位错密度明显增加,相应地硬度则从71 HV0.1明显提高到201 HV0.1。随退火温度从125℃增加到280℃,HPT工业纯铝(CP-Al)的平均晶粒尺寸从486 nm增加到1130 nm,硬度从66 HV0.1降低为55 HV0.1,表明CP-Al的平均晶粒尺寸和硬度随退火温度的提高呈线性增加和线性下降趋势。当退火温度高于195℃时,具有较高Mg含量的HPT Al-Mg铝合金退火后硬度将大幅度下降。但当退火温度低于195℃时,具有较高Mg含量的HPT Al-Mg铝合金退火后硬度下降的趋势与CP-Al类似,表明具有较高Mg含量的HPT Al-Mg铝合金表现出更好的低温热稳定性。基于实验结果,讨论了Mg含量对HPT Al-Mg铝合金强化效果的影响以及高Mg含量HPT Al-Mg铝合金低温热稳定性良好的原因。

关键词(KeyWords)： Al-Mg铝合金;高压扭转;退火;微观结构;硬度

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金联合基金培育项目(U1710124);国家自然科学基金联合基金重点项目(U1664254)

作者(Author): 王圣楠,刘满平,陈健,王晓芬,薛周磊

DOI: 10.13289/j.issn.1009-6264.2020-0180

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