超塑预处理对Al-Zn-Mg-Cu铝合金显微组织及力学性能的影响  

Microstructure and Mechanical Properties of Al-Zn-Mg-Cu Alloy by Superplastic Pre-treatment

作　　者：郑青春[1] 刘志义[1] 宁爱林[1] 曾苏民[1] 

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《金属热处理》2005年第12期23-26,共4页Heat Treatment of Metals

基　　金：重庆市院士基金项目(2000-6289);湖南省教育厅资助项目(03C444)

摘　　要：通过力学性能测试、扫描电镜和透射电镜观察,研究了传统处理工艺(conventional treatment,CT)和超塑预处理(superplastic pre-treatment,SPPT)对A l-Zn-Mg-Cu铝合金组织和性能的影响。结果表明,采用超塑预处理使铝合金晶粒细化到11μm,而传统工艺处理后的晶粒尺寸为30μm;超塑预处理使A l-Zn-Mg-Cu铝合金抗拉强度提高3.5%,塑性提高25.7%。通过透射电镜观察发现:经超塑预处理后时效析出相细小、弥散,晶界析出相(grainboundary precipitates,GBP)较小、晶界无析出带(precipitates free zone,PFZ)也较窄,这种组织特性可使合金得到较好的力学性能。The effects of conventional treatment（CT）and superplastie pre-treatment （SPPT）on the microstructure and mechanical properties of the A1-Zn-Mg-Cu alloy were investigated by means of mechanical properties test, SEM and TEM. The results show that the average grains size of the alloy was 11 μm and 30μm respectively by SPPT and CT. The SPPT enhanced the alloy tensile strength for 3.5% in ultimate,elongation for 25.7%. TEM observation shows that after the alloy treated by SPPT,its second phase particles are more refined and dispersed, grain boundary precipitates （GBP） are smaller, precipitates free zone （PFZ） are narrower. The mechanical properties of the alloy are excellent with this microstructure.

关 键 词：AL-ZN-MG-CU铝合金 超塑预处理 晶粒细化 显微组织 力学性能 

分 类 号：TG166.3[金属学及工艺—热处理]