振动对消失模铸造Al-18Si/AZ91D双合金界面组织和力学性能的影响

Effect of vibration on the interface micro-structure and mechanical properties of lost foam casting Al-18Si/AZ91D double-alloy

研究了机械振动对消失模铸造Al-18Si/AZ91D双合金界面组织和力学性能的影响。结果表明,施加振动之后,Al-18Si/AZ91D双合金结合界面的金属间化合物(IMCs)层厚度由715.7μm减小到575.4μm,从而消减了界面存在的脆性相;振动还消除了Al_(3)Mg_(2)层存在的粗大初晶Si,将其转化为细小而分散的Mg_(2)Si;此外,由于高Si含量的影响,施加振动对Al-18Si/AZ91D表现出明显的破除氧化膜的作用,这有利于减少界面缺陷,促进元素扩散。剪切结果显示,施加振动之后,Al-18Si/AZ91D双合金的平均剪切强度从49.7MPa提升到65.2MPa。

The effect of mechanical vibration on the interface micro-structure and mechanical properties of lost foam casting Al-18Si/AZ91D double-alloy has been studied.The results show that the thickness of the inter-metallic compounds(IMCs)layer at the Al-18Si/AZ91D double-alloy bonding interface decreases from 715.7μm to 575.4μm after applying vibration,thereby eliminating the brittle phase existing at the interface;the vibration also eliminates the existence of the Al_(3)Mg_(2) layer.The coarse primary Si is converted into fine and dispersed Mg_(2)Si;in addition,due to the influence of high Si content,the application of vibration on Al-18Si/AZ91D shows an obvious effect of breaking the oxide film,which is beneficial to reduce the interface defects and facilitate element diffusion.The shear results show that the average shear strength of the Al-18Si/AZ91D double-alloy increases from 49.7MPa to 65.2MPa after applying vibration.