摘要
通过力学性能、剥落腐蚀性能测试,研究回归再时效(RRA)热处理对合金力学性能、剥落腐蚀性能的影响,通过透射电镜观察分析微观组织与合金性能之间的关系。实验研究结果表明:T6态下,合金的强度较高,但其抗剥落腐蚀性能较差;经过RRA热处理后,合金的抗剥落腐蚀性能提高,峰值强度较T6态没有下降;经过RRA处理(100℃/24 h预时效+170℃/120 min回归+100℃/24 h再时效)后,合金的晶内析出相较为粗大,但其强度较高,抗拉强度、屈服强度分别是623 MPa、554 MPa,合金的晶界析出相η相粗大且不连续分布,对应了较好的抗剥落腐蚀性能,显示了较好的综合性能。
The effect of retrogression and re-aging(RRA) treatment on the mechanical properties and exfoliation corro- sion resistance of A1-Zn-Mg-Cu alloy was investigated by mechanical property testing and exfoliation corrosion(EXCO) resistance testing. The relationship between microstructure and properties of the alloy was analyzed by TEM'. The results show that under the condition of T6 treatment, the alloy has higher strength but worse EXCO resistance. After RRA treatment, the EXCO resistance is improved while the peak strength does not decline compared to the T6 treatment. After pre-aging at 100 ~C for 24 h, retrogressing at 170 ~C for 120 min and then re-aging at 100 ~C for 24 h, the precipitated phase in the crystal of the alloy is coarser but of higher strength. The tensile strength and yield strength are 623 MPa and 554 MPa, respectively. The precipitated phase rl at the grain boundary is coaser and of a discontinuous distribution, reflecting good EXCO resistance and over-all properties.
出处
《矿冶工程》
CAS
CSCD
北大核心
2012年第4期101-105,共5页
Mining and Metallurgical Engineering
基金
国家自然科学基金项目(51171209)