激光冲击强化对AZ91镁合金的电化学腐蚀行为的影响

Effect of Laser Shock Processing on Electrochemical Corrosion Behavior of AZ91 Magnesium Alloy

采用电化学测量技术和透射电镜,研究了激光冲击强化(LSP)后的AZ91镁合金在质量分数为3.5%的NaCl溶液中的耐蚀性能。结果表明:经过激光冲击后,AZ91镁合金内产生大量位错,大量的位错发展为位错缠结。在3.5%NaCl溶液中,激光冲击后的镁合金阻抗值显著增加,腐蚀电流密度显著降低。随着激光冲击次数的增加,AZ91镁合金的自腐蚀电位正移,腐蚀电流密度降低,耐腐蚀性能提高。

The effect of laser shock processing （LSP） on electrochemical corrosion behavior of AZ91 magnesium alloy in NaCI solution of mass fraction of 3. 5 % is studied by using electrochemical technique and transmission electron microscopy. The results show that a lot of dislocations reduce in the alloy after LSP. Impedance of AZ91 magnesium alloy increases significantly and the electric current density reduces significantly after LSP. With the impact times of LSP increasing, the self-corrosion potential of AZ91 Mg alloy begin to move towards a positive direction, the corrosion current destiny declins while the corrosion resistance is improved in 3.5 % NaCl solution.