Mg-9Al-1Si-1SiC复合材料ECAP变形组织及力学性能研究  

Study on Microstructure and Mechanical Properties of Mg-9Al-1Si-1SiC Composite Deformed by ECAP

作　　者：张晶辉[1] 李子岩 赵兴国[2] 王红霞[2] ZHANG Jinghui;LI Ziyan;ZHAO Xingguo;WANG Hongxia(Shanxi Polytechnic College,Taiyuan 030006,China;School of Material Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]山西职业技术学院,山西太原030006 [2]太原理工大学材料学院,山西太原030024

出　　处：《热加工工艺》2018年第15期104-108,共5页Hot Working Technology

基　　金：山西省自然科学基金项目(201701D121045);国家自然科学基金青年基金项目(51301118)

摘　　要：利用半固态搅拌辅助超声处理复合法成功制备了Mg-9Al-1Si-1SiC（wt%）复合材料,并在350℃以Bc路径对其进行等通道转角挤压（ECAP）,研究了ECAP变形道次对复合材料显微组织和力学性能的影响。结果表明：1道次ECAP变形能够显著细化复合材料的基体晶粒,但是第二相未明显碎化。随变形道次增加到2和3次,第二相碎化程度增加,但仍然聚集,基体局部区域晶粒长大,出现粗晶和细晶两个区域;变形达到4道次后,复合材料的基体晶粒又变得均匀,β-Mg_（17）Al_（12）和Mg_2Si相均得到有效的碎化并且在基体中的分布趋于均匀。复合材料的抗拉强度随变形道次增加逐渐增加,伸长率先减小后增加。变形4道次后,复合材料力学性能最大：抗拉强度和伸长率分别达到283 MPa和14.79%,与铸态相比,抗拉强度和伸长率分别提高66.5%和127.5%。Mg-9Al-1Si-1SiC（wt%）composites were successfully prepared by semi-solid stirring assisted ultrasonic treatment.The materials were subjected to equal channel angular pressing（ECAP）at 350℃with the Bc route.The effects of ECAP deformation pass on the microstructure and mechanical properties of the composite were investigated.The results show that the matrix grains are refined significantly,but the second phases are not fragmented obviously after one pass ECAP.The degree of fragmentation of the second phase increases with the increase of the number of deformation pass to 2,3 passes,but it still accumulates,the grains grow up in some areas of the matrix,and there are two regions of coarse and fine grains.After 4passes of deformation,the matrix grain of the composite becomes homogeneous,both theβ-Mg_（17）Al_（12）and Mg_2Si phases are effectively crushed and the distribution in the matrix tends to be uniform.The tensile strength of the composite increases gradually with the increase of the deformation pass,and the elongation decreases firstly and then increases.After 4 passes of deformation,the mechanical properties of the composite are the largest,the tensile strength and elongation reach 283 MPa and 14.79%,respectively.Compared with as cast composite the tensile strength and elongation increase by 66.5%and 127.5%,respectively.

关 键 词：Mg-9Al-1Si-1SiC复合材料 等通道转角挤压(ECAP) 显微组织 力学性能 

分 类 号：TG379[金属学及工艺—金属压力加工]