多向压缩对ZK60镁合金微观组织和耐腐蚀性能的影响

Effect of multidirectional compression on microstructure and corrosion resistance of ZK60 magnesium alloy

为研究温度对铸态ZK60镁合金多向压缩过程中组织演变的影响,测试多向压缩后试样的电化学极化曲线,分析试样的腐蚀行为。结果表明:随着压缩温度的提升,试样晶粒得到一定程度的细化,且晶粒变得更加均匀;随着压缩温度的上升,合金的自腐蚀电流密度先上升后减小,400℃下晶粒充分破碎长大,试样的晶粒细化且均匀,表面可形成致密的氧化膜,析出相被破碎细化并回溶到基体中,微电偶腐蚀作用减弱,该温度下压缩试样自腐蚀电流密度最低。

This paper aims to investigate the effect of temperature on the microstructure evolution of cast ZK60 magnesium alloy in the process of multidirectional compression. The investigation involves testing the electrochemical polarization curve of the samples after multidirectional compression and analyzing the corrosion behavior of the samples. The results show that with the increase of compression temperature, the grains of the sample are refined to a certain extent, and become more uniform;the self-corrosion current density of the alloy first increases and decreases latter. At 400 ℃, the grains of the sample crush and grow fully;with the grains refined and uniform, the surface can form a dense oxide film;the broken and refined precipitated phase is dissolved back into the matrix;the micro-galvanic corrosion is weakened;and the lowest self-corrosion current density of the compressed sample occurs at this temperature.