论文部分内容阅读
主要研究了SiC颗粒增强镁基复合材料在不同挤压比、不同挤压温度下进行挤压后,SiC颗粒对镁合金基体中的动态再结晶现象影响。结果表明:挤压过程中颗粒周围产生了颗粒变形区(PDZ),并且颗粒变形区在低温挤压时以细小动态再结晶晶粒为主。颗粒促进动态再结晶晶粒形成的主要原因是颗粒周围较高的位错密度以及大的晶粒取向梯度。SiC颗粒对镁合金基体动态再结晶的影响主要有两方面:一方面,颗粒促进动态再结晶的形核以及生长,另一方面,当再结晶晶粒晶界碰到颗粒时,颗粒阻止了晶粒的继续长大。
The effects of SiC particles on the dynamic recrystallization of magnesium alloy matrix were studied mainly after the SiC particle reinforced magnesium matrix composites were extruded at different extrusion ratios and different extrusion temperatures. The results show that the particle deformation zone (PDZ) is generated around the particles during extrusion, and the grain deformation zone is dominated by fine and dynamic recrystallization grains at low temperature. Particles promote dynamic recrystallization grain formation is mainly due to the higher dislocation density around the grain and a large grain orientation gradient. On the one hand, the particles promote the nucleation and growth of dynamic recrystallization. On the other hand, when the recrystallized grain boundary collides with the particles, the particles prevent the crystallization Granules continue to grow up.