冷却速率对高Zn含量AlZnMgCu合金晶间腐蚀性能的影响

Effect of Cooling Rate on Intergranular Corrosion Properties of AlZnMgCu Alloys with High Zn Content

通过末端淬火的方法结合硬度、电导率、光学显微镜和扫描电镜等手段研究了淬火冷却速率对高Zn含量AlZnMgCu合金晶间腐蚀性能的影响规律。结果显示,随着冷却速率减小,硬度先降低后不变,晶间腐蚀性能恶化,而电导率先缓慢升高后迅速升高;随着冷却速率减小,合金逐渐析出淬火η相,淬火η相的尺寸和数量随冷却速率减小而增大。

The effect of cooling rate on intergranular corrosion of AlZnMgCu alloy with high Zn content was investigated by means of end-quenching technique,hardness,electrical conductivity,optical microscopy and scanning electron microscopy.The results show that with the decrease of cooling rate,the hardness first decreases and then stays the same,the intergranular corrosion resistance deteriorates,and the electrical conductivity first increases slowly and then increases rapidly.As cooling rate decreases,the alloy gradually precipitates the quenchedηphase,and the size and quantity of quenchedηphase increase.