均匀化工艺对Al-4.46Mg合金腐蚀和疲劳性能的影响

Effect of homogenization on corrosion and fatigue performance of Al-4.46Mg alloy

研究480℃/20 h,430℃/2 h+490℃/12 h和500℃/16 h这3种均匀化工艺对Al-Mg合金腐蚀性能和疲劳性能的影响;通过晶间腐蚀(IGC)和慢应变速率拉伸(SSRT)腐蚀研究这3种工艺对Al-Mg合金O态板材的腐蚀性能的影响;通过疲劳裂纹扩展速率和Kahn撕裂实验研究这3种工艺对Al-Mg合金O态板材疲劳性能的影响。研究结果表明:与其他2种工艺相比,经430℃/2 h+490℃/12 h均匀化后得到的板材抗晶间腐蚀性能最佳,腐蚀速率为2.287 8 mg/cm^2,应力腐蚀敏感指数ISSRT最小,为0.068;经430℃/2 h+490℃/12 h均匀化后得到的板材在高应力强度因子范围下抗裂纹扩展性能最佳,其单位面积裂纹形核功与经500℃/16 h处理得到的板材的形核功接近。

The effects of homogenization on corrosion and fatigue performance of Al-Mg alloy were studied after being homogenized using three homogenization technologies,i.e.,480℃/20 h,430℃/2 h+490℃/12 h and 500℃/16 h,the corrosion performance of Al-Mg alloy sheets were tested by intergranular corrosion(IGC)and slow strain rate testing(SSRT),the fatigue performance of Al-Mg alloy sheets were tested by fatigue crack growth rate testing and Kahn tear test.The results show that Al-Mg alloy after homogenization by 430℃/2 h+490℃/12 h has the best intergranular corrosion resistance,the rate of corrosion is 2.287 8 mg/cm2,and the susceptibility index of slow strain rate test is 0.068.Al-Mg alloy after homogenization by 430℃/2 h+490℃/12 h has the best crack propagation resistance in the range of high intensity factor,and the unit initiation energy is close to that of the Al-Mg alloy sheets after annealing homogenization through the treatment at 500℃for 16 h.