摘要
对人工时效后的LY12合金进行了不同温度系列拉伸试验,采用SEM和光镜对断口及其附近的显微组织进行观察,研究了温度对LY12合金拉伸变形行为的影响。结果表明,LY12合金正常时效时析出相的主要成分为Al2CuMg,随温度的逐步降低,析出相发生脆性断裂的可能性更大。同时析出相与基体分离需要吸收更多外界能量,从而使LY12合金的抗拉强度与屈服强度随温度的逐步降低单调增加;随温度的逐步降低,析出相的脆性断裂降低了对位错的阻碍作用,使位错滑移距离增长,因此材料的伸长率呈增长趋势。
The LY12 alloy aider artificial aging was carded out tensile test at different temperature.The fracture and the microscopic structure near fracture were obsered by SEM and metallographic microscope, the influnce of temperature on tensile deformation behavior of LY12 alloy was researched .The results show that the main composition of LY12 alloy precipitation is Al2CuMg, and the possibility of brittle rapture of precipitation in LY12 alloy increases with temperature gradually reducing. At the same time, it needs more energy to separate precipitation and matrix. As the result, the tensile strength and yield strength increase monotonously as the temperature gradually reducing,and the brittle rupture of precipitation reduces counteract effect to dislocation, the dislocation slipping distance increases, so the elongation of the material exhibits increasing tendency.
出处
《热加工工艺》
CSCD
北大核心
2007年第10期28-29,34,共3页
Hot Working Technology
关键词
LY12合金
低温拉伸
微观组织
LY12 alloy
low temperature tensile
microstructure
