断续时效工艺对7N01铝合金组织性能的影响  

Effect of interrupted aging process on microstructure and mechanical properties of 7N01 aluminum alloy

作　　者：田洪雷 孙琳 邓运来[2] TIAN Honglei;SUN Lin;DENG Yunlai(CRRC Qingdao Sifang Co.,Ltd.,Qingdao 266111,China;School of Materials Science and Engineering,Central South University,Changsha 410083,China)

机构地区：[1]中车青岛四方机车车辆股份有限公司,山东青岛266111 [2]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《轻合金加工技术》2023年第12期29-35,39,共8页Light Alloy Fabrication Technology

基　　金：中国国家铁路集团有限公司科技研究开发计划(K2021J040)。

摘　　要：采用透射电子显微镜,维氏硬度计和电子万能试验机研究了断续时效工艺对7N01铝合金的时效硬化行为、力学性能和显微组织的影响。研究结果表明:T5I4态合金晶内析出相平均粒径及体积分数均远小于T5及T73态合金的,其晶界析出相为连续分布的细密点状相,且无明显无沉淀析出带,最终使合金获得较好的室温拉伸性能。当合金在T5I4断续时效基础上再进行第三级高温再时效,到达峰时效(T5I6态)后,其室温拉伸性能再次提升。当在T5I6断续时效的基础上继续时效达到过时效(T5I7态)后,合金的强度与T5I6态相比有所降低,但依然高于T5I4态及T5、T73态样品的。The effect of interrupted aging process on microstructure and mechanical properties of 7N01 aluminum alloy was investigated by transmission electron microscope,Vickers hardness tester and electronic universal testing machine.The results show that the average diameter and volume fraction of the precipitates in T5I4 alloy are much smaller than those in T5 and T73 alloys.The grain boundary precipitates are fine and continuously distributed and no obvious precipitation free zone is observed in T5I4 alloy.As a result,the T5I4 alloy presents good tensile properties at room temperature.When the alloy is re-aged at the third high temperature on the basis of T5I4 interrupted aging,the tensile properties at room temperature are improved again after reaching peak aging(T5I6).The strength of the alloy decreases when the aging reaches over aging(T5I7)on the basis of T5I6,while the strength of the T5I7 alloy is still higher than that of T5I4,T5 and T73 alloys.

关 键 词：7N01铝合金 断续时效工艺 显微组织 力学性能 

分 类 号：TG166.3[金属学及工艺—热处理]