摘要
对多种成分的铸造合金的加速腐蚀实验、电化学检测、金相分析、X射线衍射和电子探针分析,证实了各种成分的合金都发生晶界腐蚀;随着铝含量的增加,由晶界富铝相腐蚀逐渐过渡到晶界富锌相腐蚀;晶界腐蚀是Zn-Al合金老化的主要原因。在此基础上,提出了改进Zn-Al合金耐腐蚀性能的几种可能途径:适当提高铝含量,表面处理,加入合金元素等。
Accelerated corrosion experiment, electrochemical measurement, x-ray diffraction, metallomicroscope and electronmicroprobe have been used to investigate a series of the casting alloy with different aluminium content by mass fraction, Results prove that: all of the alloy samp es take place intergranular corrcsion; a transition from corrosion by Al-riched phase to one by Zn-riched phase exists as the aluminium content increases; main cause of the aging is intergranular corrosion. Several methods to improve corrosion-resistance of the alloy are suggested: to suitably increase aluminium content (e. g. 43％Al), passivate the alloy surface and add some alloying elements.
关键词
耐磨合金
锌基合金
铝合金
老化
Abrasion resistance alloys
Zinc-containing alloys
Aluminium alloys
Aging mechanism
Aging tests
Aging stability
