Zn对AM60B镁合金显微组织和力学性能的影响

Influence of Zn on Microstructure and Mechanical Properties of AM60B Magnesium Alloy

以AM60B为基体合金,采用ICP、OM、SEM、EDS和拉伸试验机等研究不同Zn含量对AM60B合金组织和力学性能影响.研究结果表明:随着Zn元素含量的增加,AM60B镁合金的组织主要由α-Mg基体相,Mg2Zn和Al9Mn11相组成,其抗拉强度、屈服强度和硬度先增加后减小,并在Zn元素含量达到4%时达到峰值,分别为248 MPa、123 MPa和70.4HV.其拉伸断口为准解理断口,该合金的强化机制为细晶强化、固溶强化和第二相析出强化,其中细晶强化起主导作用.

The raw material used for casting AM60 B mixed with different contents of Zn. The effects of the addition of Zn element to AM60 B magnesium alloy on the microstructure,mechanical properties were studied by means of inductive coupled plasma emission spectrometer,optical microscope,scanning electron microscope,energy dispersive spectrometer and tensile testing machine. The results show that the alloy consists of the α-Mg matrix phase,the Mg2 Zn and Al9Mn11 phase appears when the content of Zn reaches 5%. The UTS,Yield Strength and hardness of AM60 B all increase with the increase of content of Zn,and they reaches the peak value,which 248 MPa,123 MPa and 70. 4HV at the Zn addition of 4wt% separately. The fracture of tensile is quasi-cleavage fracture. The strengthening mechanism of the alloy perhaps included fine-grain strengthening,solution strengthening and second-phase strengthening,in which fine-grain strengthening plays a leading role.