在熔炼Mg-5Al-1.2Zn-0.8Sb合金过程中,以Mg-10Y中间合金形式加入0～2.5％的(质量分数,下同)稀土元素,研究了不同添加量的Y元素对显微组织、力学性能及腐蚀性能的影响.实验结果表明:经过适量稀土Y微处理后的合金具有细小均匀的铸态组织,晶粒尺寸维持在30μm左右.Y元素从0变化到2.5％过程中,合金室温抗拉强度在0～1.5％范围内增加,在1.5％ ～2.5％范围内降低,而高温强度则一直呈现升高趋势.稀土Y对合金的腐蚀性能具有改善作用,当Y含量为1.0％时合金耐蚀性能较好,过量加入Y元素对腐蚀性能有负面影响.%The effects of rare earth Y on microstructure, mechanical properties and corrosion resistance of Mg-5Al-l.2Zn-0.8Sb alloy are studied when Y element is added into melt in the form of Mg-lOY interalloy with the range of 0 ~2.5% (mass fraction, similarly hereinafter). The experimental results indicate that Y element has the strong refinement on cast microstructure, the grain size maintains about 30 micron. When Y element changes from 0 to 2. 5% , room temperature tensile strength of the alloy is increased in the range of 0 to 1.5% and decreased in the range of 1. 5 % to 2. 5 % , while its high temperature strength is improved in the range of 0 to 2. 5 % always. Y element can improve corrosion resistance of the alloy, when Y content is 1. 0% , its corrosion resistance is more better, excessive Y added has negative effects on corrosion behavior of the specimen.
展开▼
