均匀化处理对7150铝合金冲击性能影响

Study of homogenization treatment on 7150 aluminum alloy impact properties

采用光学显微镜、SEM和冲击试验机研究了均匀化处理后的7150铝合金圆铸锭的冲击性能。7150铝合金圆铸锭晶界存在大量的网状非平衡析出相,在晶粒内部同时也存在部分颗粒状析出相。经过均匀化处理后,晶界与晶粒内部的析出相均出现了回溶现象。铸态晶界处析出相为MgZn2和Al2Cu,经过高温长时间均匀化已大部分回溶,同时仍残留有部分Al6(FeCu)析出相,该相是由不稳定的FeAl6化合物转变而来,均匀化处理对Al6(FeCu)相的形貌及成分未产生影响。经过均匀化热处理后,改变了析出相数量和分布,增加了材料的塑性,试样的抗冲击性能得到提高,更有利于适应恶劣的服役环境。

The impact properties of homogenized 7150 aluminum alloy bar were studied by optical microscope,SEM and impact testing machine.There are a lot of network non-equilibrium precipitates in the grain boundary of 7150 aluminum alloy bar,and some granular precipitates also exist in the grains.After homogenization,the precipitates the grains boundary and in the grain are redissolved.MgZn2 and Al2Cu precipitates at the grain boundary as cast are mostly redissolved after homogenization at high temperature for a long time,while some Al6(FeCu) precipitates remain.This phase is transformed from unstable FeAl6 compound.Homogenization treatment has no effect on the morphology and composition of Al6(FeCu) phase.After homogenization heat treatment,the amount and distribution of precipitates are changed,the plasticity of the material is increased,and the impact resistance of the sample is improved,which is more conducive to adapt to the harsh service environment.