摘要
The effects of Sr and Y with different contents on the microstructure and corrosion resistance of AZ31 alloy were investigated. The results indicate that the addition of Sr can obviously reduce the grain size of AZ31 alloy and transform β-Mg 17 Al 12 phase from continuous network to scattered form. Simultaneously, Al 4 Sr phase distributed along the boundaries of grains is formed in AZ31-Sr magnesium alloys. The addition of Sr is not as effective as the simultaneous addition of Sr＋Y for the refinement of grains, and Al 2 Y and Al 3 Y phases are distributed both in intracrystalline and along grain boundaries. The corrosion resistance is improved slightly in AZ31 alloy with simultaneous addition of 0.5%Sr＋Y. Due to its smallest corrosion current density and corrosion rate, the corrosion resistance of AZ31-0.5%Sr-1.5%Y magnesium alloy is proved the best.
研究不同含量的Sr和Y对AZ31镁合金组织与耐蚀性能的影响。结果表明:添加Sr可以明显减小AZ31合金的晶粒尺寸,使β-Mg17Al12相从连续网状结构转变为弥散均匀分布颗粒状,并在AZ31-xSr合金中生成沿晶界分布的Al4Sr相。同时添加Sr和Y的晶粒细化效果好于单独添加Sr的。生成晶内和沿晶界分布的Al2Y和Al3Y相。在AZ31镁合金中加入0.5%Sr+xY,其耐蚀性能明显提高。AZ31-0.5%Sr-1.5%Y合金的腐蚀电流和腐蚀速率最小,耐蚀性能最好。
基金
Project(2007CB613702)supported by the National Basic Research Program of China
Project(2006AA4012)supported by the Research Program Foundation of CQ CSTC, China
Project(2008BB4323)supported by the Natural Science Foundation of CQ CSTC, China
