摘要
通过对Mg-6Zn-3Cu (ZC63)合金进行XRD衍射、硬度及拉伸性能的测试,研究了浇注温度对其组织和性能的影响。研究表明,随着合金的浇注温度增高,ZC63镁合金的晶粒尺寸不断增大,降低浇注温度可细化晶粒,且降低生产成本。当浇注温度为680℃,合金组织比较细小均匀,力学性能较高,其抗拉强度和伸长率分别为205 MPa和13.2%。ZC63镁合金铸态的断口主要由解理面和撕裂棱组成,具有准解理断裂特征。浇注温度越低,解理面尺寸越小,撕裂棱占比越多,表明合金的塑性变形能力越强。
The effect of pouring temperature on the microstructure and properties of Mg-6Zn-3Cu(ZC63) alloy was investigated by XRD, hardness and tensile properties tests. It is found that the grain size of as-cast ZC63 alloy increase with the pouring temperature increasing. Reducing pouring temperature can refine grain size and reduce production cost. When the pouring temperature is 680℃, the microstructure is much finer and more uniform, and the mechanical properties of ZC63 alloy is better. The tensile strength and elongation of ZC63 alloy poured at 680℃are 205 MPa and 13.2%, respectively. The fracture surfaces of as-cast ZC63 alloy mainly consist of cleavage facet and tearing ridge, showing a quasi-cleavage fracture characteristic. The size of the cleavage facet tends to be smaller and the proportion of the tearing ridge is improved with the decrease of the pouring temperature, which indicates that the ZC63 alloy has more stronger plastic deformation ability at lower pouring temperature.
引文
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