微合金化对原位合成(Al_2O_3+Al_3Zr)_p/A356复合材料显微组织与力学性能的影响  

Effect of Micro-alloying on Microstructure and Mechanical Properties of In-Situ Synthesized(Al_2O_3+Al_3Zr)_p/A356 Composites

作　　者：汪长勤[1] 赵玉涛[1] 张松利[1] 陈刚[1] 孙洪强[1] 

机构地区：[1]江苏大学材料科学与工程学院,镇江212013

出　　处：《机械工程材料》2010年第1期33-37,共5页Materials For Mechanical Engineering

基　　金：国家"863"高新技术研究发展计划资助项目(2007AA03Z5481);江苏省六大人才高峰项目(06-D-021);江苏省科技成果转化项目(BA2005054);江苏省高技术研究项目(BG2005026);教育部科技研究重点项目(2070381)

摘　　要：采用微合金化和熔体原位合成法制备了(Al2O3+Al3Zr)p/A356复合材料,研究了微合金化对复合材料显微组织和力学性能的影响。结果表明:微合金化后复合材料中Al2O3和Al3Zr的尺寸更加细小,在0.5～2μm之间,分布更加均匀,颗粒形貌趋于球形,周边圆滑;其力学性能较未添加合金元素的复合材料有明显提高;当添加0.2%Mn+0.2%Cr+0.3%RE时,复合材料的抗拉强度、屈服强度和伸长率达到379 MPa,297 MPa和7.5%,分别提高了32.5%,37.5%和59.5%;其断裂形式属韧性断裂;其强化机制主要有Orwan强化、细晶强化、固溶强化和位错强化。（Al2O3＋Al3Zr）p/A356 composites were synthesized by micro-alloying and melt in-situ reaction technology. The effect of micro-alloying on microstructure and mechanical properties of the composites was investigated. The results indicate that the reinforced particulates A12 03 and A13 Zr of the composites after alloying became smaller with the size at about 0. 5 -- 2 t^m, the distribution became more homogeneous, the morphology became spherical and the surrounding was blunt. The mechanical properties of the composites were greatly enhanced, compared with that of the composites without alloying element addition. The tensile strength, yield strength and elongation of the （Al2O3＋Al3Zr）p/A356 composites reached 379 MPa, 297 MPa and 7. 6%, which increased 32. 5%, 37. 5%and 59.5% respectively, after 0. 2wt%Mn, 0. 2wt%Cr and 0. 3wt%RE were added. The fracture of the composites was ductile fracture. The strengthening mechanisms included Orowan strengthening, grain-refined strengthening, solid-solution strengthening and dislocation strengthening.

关 键 词：微合金化 铝基复合材料 原位合成 力学性能 

分 类 号：TB331[一般工业技术—材料科学与工程]