淬火水温对Al-Cu-Mn高强铸造合金性能的影响

Influence of Quenching Water Temperature on Mechanical Property of High Strength Cast Al-Cu-Mn Alloy

研究了淬火水温对Al-Cu-Mn高强铸造铝合金时效处理后拉伸强度和伸长率的影响,并分析其微观组织结构。结果表明:60℃水温淬火可以获得实验中最高的拉伸强度和最大的伸长率。其原因在于淬火水温不同,时效处理后试样的微观组织结构有所不同。在30、40℃较低温度淬火,冷却速率高导致了淬火裂纹和晶界模糊;在100℃水温淬火,冷却速率慢,在晶界析出较多条状物且晶粒尺寸增大,晶内二次T相偏聚。而在60℃水温淬火试样获得了有利于提高强度和伸长率的微观组织结构。

The influences of quenching water temperature on the tensile strength and elongation of high strength cast Al-Cu-Mn alloy after aging treatment were investigated,and its microstructure was also analyzed.The results show that,when the water temperature is 60 ℃,the highest tensile strength and elongation value can be gained.The reason can be attributable to the different microstructure of samples quenched under different temperature water.The quenching treatment in 30 ℃ or 40 ℃ water leads to bad microstructure such as quenching cracks,fuzzy grain boundary and so on.While,the quenching treatment at 100 ℃ water leads to larger grain particles,block precipitations on the grain boundary and segregation of the second T phase in the grain.However,the quenching treatment in 60 ℃ water can gain the microstucture in favor of improving the tensile strength and elongation of Al-Cu-Mn cast alloy.