摘要
采用正交试验对含0.25%(质量分数)钪Al-Zn-Mg-Zr合金的双级时效进行了工艺优化,研究了双级时效工艺参数(预时效温度和时间、终时效温度和时间)对合金力学性能和电导率的影响,观察了最佳工艺处理后合金的显微组织。结果表明:对该合金综合性能,尤其是力学性能影响程度由大到小的参数依次为终时效温度、终时效时间、预时效时间、预时效温度;该合金适宜的双级时效工艺为120℃×4h+140℃×12h,经该工艺处理后,合金的抗拉强度为553 MPa,屈服强度为534 MPa,伸长率为12.0%,电导率为37.3%IACS;合金基体组织中弥散分布着η′相以及Al3(Sc,Zr)粒子,有助于合金强度以及抗应力腐蚀性能的提高。
The two-stage aging process optimization was conducted on Al-Zn-Mg-Zr alloy containing 0.25wt% scandium by orthogonal experiment. The influences of the two-stage aging process parameters （pre-aging time and temperature, final-aging time and temperature） on the mechanical properties and electrical conductivity of the alloy were studied and the microstructure of the alloy after treatment by this process was observed. The results show that the influence significance of the factors on the comprehensive performance especially mechanical properties of the alloy was ranked from high to low as follows., final-aging temperature, final-aging time, pre-aging time and pre-aging temperature. The suitable two-step aging process of the alloy was determined as pre-aging at 120 ℃ for 4 h followed by final-aging at 140 ℃ for 12 h. After treated with this process, the tensile strength, yield strength, elongation and electrical conductivity of the alloy was 553 MPa, 534 MPa, 12.0%, 37.3GIACS respectively. The η＇ phase and A13 （Sc, Zr） particles distributed dispersively in the base structure of the alloy, contributing to the improvement the strength and stress corrosion resistance of the alloy.
出处
《机械工程材料》
CAS
CSCD
北大核心
2016年第8期39-42,48,共5页
Materials For Mechanical Engineering
基金
湖南省教育厅科学研究项目(14C0379)
