中文摘要：

为由热挤出直接再循环 AZ91D 镁合金碎片的一个方法被学习。各种各样的微结构分析用光显微镜学的技术被执行，扫描电子显微镜学(SEM ) 和精力散光谱学(版本) 。微结构观察表明所有再循环的标本由于动态再结晶由好谷物组成了。再循环的标本的主要加强机制是谷物精炼加强，氧化物的同类的分发猛抛。当碎片与 40:1 的挤出比率被渗出时，渗出的材料的单个碎片的接口没被识别。碎片的氧化层被压缩的高度分解为片并且砍在 40:1 的挤出比率下面的力量。到失败的最终的张力的力量和延伸与增加挤出比率增加了。有 40:1 的挤出比率的再循环的标本演员组标本显示出 342.61 MPa 和更高的延伸的更高最终的张力的力量到 11.32% 的失败，与那些相比。

英文摘要：

A method for recycling AZ91D magnesium alloy scraps directly by hot extrusion was studied.Various microstructural analyses were performed using the techniques of optical microscopy,scanning electron microscopy（SEM）and energy dispersive spectroscopy（EDS）.Microstructural observations revealed that all the recycled specimens consisted of fine grains due to the dynamic recrystallization.The main strengthening mechanism of the recycled specimen was grain refinement strengthening and homogeneous distribution of oxide precipitates.The interfaces of individual scraps of extruded materials were not identified when the scraps were extruded with the extrusion ratio of 40-1.Oxidation layers of the scraps were broken into pieces by high compressive and shear forces under the extrusion ratio of 40-1.The ultimate tensile strength and elongation to failure increased with increasing the extrusion ratio.Recycled specimens with the extrusion ratio of 40：1 showed higher ultimate tensile strength of 342.61 MPa and higher elongation to failure of 11.32%,compared with those of the cast specimen.