机械研磨对医用Mg-6Al-2Ca合金表面组织和性能的影响

Effect of Mechanical Polishing on Microstructure and Properties of Medical Mg-6Al-2Ca Alloy Surface

通过SEM、表面性能分析和电子拉力试验等手段,研究了表面机械研磨处理对医用Mg-6Al-2Ca镁合金表面组织和力学性能的影响。结果表明:经表面机械研磨处理后,合金表面晶体生长更为规则,其晶粒平均尺寸也越来越细化。随着表面机械研磨时间的增加,合金表面粗糙度和显微硬度也随之增大,表面接触角随之减小。表面机械研磨后,镁合金的拉伸强度和屈服强度增大,而塑性有所降低。机械研磨45 min后,合金的拉伸强度和屈服强度分别增加了29.2%和44.5%,伸长率降低了31.6%。镁合金断口以准解理断裂为主,撕裂棱和尺寸较小的空洞明显增多,表面机械研磨处理时间增加,减小了韧窝数量。

By SEM, surface properties characterization and surface electronic tensile testing and other methods, the effects of surface mechanical polishing treatment on the microstructure and properties of medical Mg-6Al-2ea alloy surface were studied. The results show that after surface mechanical polishing processing, the crystal growth of alloy surface is regular, the average grain size is becoming more and more refined. With the extension of surface mechanical polishing time, the surface roughness and microhardness of the alloy surface increase,and then the surface contact angle becomes small. After surface mechanical grinding, the tensile strength and yield strength of the alloy increase, but the plasticity decreases. After surface mechanical polishing for 45 rain, the tensile strength and yield strength of the alloy increase by 29.2% and 44.5%, respectively, and the elongation reduces by 31.6%. The fracture of magnesium alloy is given priority to quasi cleavage fracture, and the numbers of tom edges and smaller hole obviously increase. The increase of surface mechanical polishing processing time can reduce the numbers of toughening nests.