三点弯曲对镁合金AZ31降解速率影响的研究

Research on the effect of three-point bending on degradation rate of AZ31 magnesium alloy

本文主要研究三点弯曲作用力对镁合金AZ31接骨板降解性能的影响,有限元模拟设置两种不同孔形镁合金接骨板:相同直径圆孔(模型A)和不同直径圆孔(模型B),基于连续损伤理论实现其降解过程的仿真;体外降解实验中设置与有限元模拟相对应的试件A和试件B,在重要时间节点记录镁合金接骨板所产生的氢气和质量损失.通过有限元仿真与体外降解实验的结果对比可以得出:随着三点弯曲力的增加,镁合金接骨板氢气量和质损率随之增加;模型B是中间整体部分产生断裂,这种孔形使应力得到了有效分配,承受载荷比较均匀,腐蚀较为缓慢,孔形设置比较合理.

This paper mainly studies the impact of three-point bending force on degradation performance of magnesium alloy AZ31 bone fracture plate.Two different hole-shaped magnesium alloy bone fracture plates are set up in finite element simulation:same diameter round holes(model A)and different diameter round holes(model B).Based on the continuum damage theory,simulation of degradation process is realized.In the in vitro degradation experiment,specimens A and B corresponding to the finite element simulation are set,and the hydrogen generated by magnesium alloy bone fracture plate and mass loss are recorded at an important time node.Comparing the results of finite element simulation to the in vitro degradation experiments,it can be concluded that with the increase of three-point bending force,the hydrogen quantity and mass loss rate of magnesium alloy bone fracture plate increase accordingly.The hole shape of model B,a fracture of the whole part in the middle,can effectively distribute the stress,bear uniform load,and the corrosion is slower,so the hole shape is relatively reasonable.