不同Y含量对ZM21镁合金组织和力学性能的影响

Effect of Y on the microstructure and mechanical properties of Mg-2Zn-1Mn alloy

摘要:

本文主要通过OM、SEM、EDS和XRD等研究了铸态及挤压态Mg-2Zn-1Mn-xY (Y=0,0.8,2.2,wt.%) 镁合金显微组织和力学性能。由实验结果可知,稀土Y的添加,不仅可以细化铸态及挤压态合金晶粒,还可以弱化挤压态合金的基面织构强度,从而同时提高合金的强度以及韧性。本文中最优化合金挤压态Mg-2Zn-1Mn-xY合金具有良好的力学性能,与原始Mg-2Zn-1Mn合金相比,屈服强度从164MPa提高到204MPa、抗拉强度从237MPa提高到298MPa以及延伸率从12%增加到18%。

Abstract:

The microstructure and mechanical response of as-cast and extruded Mg-2Zn-1Mn-xY alloys (Y content of 0, 0.8 and 2.2 wt.%) have been investigated by optical microscope (OM), scanning electron microscope (SEM) with X-ray energy dispersive spectrometer (EDS), and X-ray diffractometer (XRD). The experiment results reveal that the addition of Y not only decrease the grain sizes of both as-cast and extruded alloys, but also effectively reduce the basal texture intensity of extruded alloys. These are two key reasons for the improvement of the strength and ductility of Mg-2Zn-1Mn-xY alloys, simultaneously. The optimized Mg-2Zn-1Mn-xY alloys after extrusion exhibits an attractive mechanical performance. Compared with the matrix material Mg-2Zn-1Mn, its yield strength increases from 164 MPa to 204 MPa, the ultimate tensile strength increases from 237 MPa to 298 MPa and the elongation increases from 12% to 18%.