Abstract：Multi-pass hot extrusion was used to prepare the Al2O3/AZ31 composite.The microstru-cture was characterized by optical microscopy, scanning electron microscopy, transmission electron microscopy, and mechanical properties were tested by Vickers hardness tester and electron universal strength tester. The results show that Al2O3 particles are uniformly distributed in AZ31 magnesium matrix by multi-pass hot extrusion. The grain refining effect of Al2O3 particles on the matrix is enhanced, and the grain size of the composite decreases significantly with the increase of the pass. During the hot extrusion process, the dislocation density around the Al2O3 particles increases, and the high-density dislocation region facilitates the dynamic recrystallization nucleation, so that the grains of the Al2O3/AZ31 composite are significantly refined. The Al2O3 particles are gradually distributed into a long strip from the initial island distribution, then distributed in a linear pattern, and finally distributed uniformly in the form of particles in the AZ31 magnesium matrix. After fourth-pass hot extrusion, the mechanical properties of Al2O3/AZ31 composite are significantly improved, and hardness, tensile strength and yield strength are 89HV, 305MPa and 198MPa, respectively. The hardness, tensile strength and yield strength increase by 19.2%, 14.8%, and 14.1%, respectively, compared with the first-pass hot extrusion.
魏帅虎, 胡茂良, 吉泽升, 许红雨, 王晔. 多道次热挤压制备Al2O3/AZ31复合材料的微观组织与力学性能[J]. 材料工程, 2019, 47(12): 85-91.
WEI Shuai-hu, HU Mao-liang, JI Ze-sheng, XU Hong-yu, WANG Ye. Microstructure and mechanical properties of Al2O3/AZ31 composites prepared by multi-pass hot extrusion. Journal of Materials Engineering, 2019, 47(12): 85-91.
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2019, Vol. 47 
