论文部分内容阅读
热轧态7249高强铝合金经固溶处理后分别进行室温空气、PAG淬火液及水淬火处理。通过拉伸实验、OM、SEM及动电位极化曲线等测试手段,研究了不同淬火介质对三级时效后合金力学性能及晶间腐蚀性能的影响。结果表明:随着淬火冷却速率的减小,实验合金基体析出相数量逐渐增多且长大粗化,导致合金时效后力学性能及导电率呈现先增大后下降的趋势,即经PAG淬火处理后,合金综合性能最优;同时合金的腐蚀电流密度和腐蚀速率变小,合金抗晶间腐蚀性能增强。
Hot-rolled 7249 high-strength aluminum alloy after solution treatment were room temperature air, PAG quenching fluid and water quenching. The tensile test, OM, SEM and potentiodynamic polarization curves were used to study the effect of different quenchant on the mechanical properties and intergranular corrosion resistance of the alloy after three-stage aging. The results show that with the decrease of quenching cooling rate, the amount of precipitated phase in the experimental alloy increases gradually and coarsens, which leads to the mechanical properties and electrical conductivity of the alloy first increase and then decrease, that is, after the PAG quenching , The alloy has the best overall performance. At the same time, the corrosion current density and corrosion rate of the alloy become smaller, and the intergranular corrosion resistance of the alloy is enhanced.