铸态AZ系镁合金一般都需要经过固溶处理才能腐蚀出晶界,不但耗时而且可能导致结果失真。尝试将乙酸-苦醇试剂用于铸态AZ系镁合金的金相腐蚀,并且在偏振光下辅以灵敏色片进行观察以得到彩色晶粒衬度。试验了不同铝含量的铸态AZ系镁合金在不同浓度乙酸-苦醇试剂和不同时间下的腐蚀效果,找到了各自的最佳腐蚀参数,得到了晶粒衬度鲜明的彩色金相照片。
Usually the grain boundaries of as-cast AZ series magnesium alloys can only he revealed after solution heat treatment which is time consuming and may lead to distorted result. Acetic picral reagent is used for the metallographic etching of as-east AZ series magnesium alloys, and the etched specimens are viewed with polarized light plus sensitive tint in order to generate color contrast. Specimens with different aluminum content are etched in acetic picral reagents with diverse concentrations and for different etching time. The optimum parameters for testing as-cast AZ series magnesium alloys are found separately and metallographic color images with vivid grain contrast are obtained.