(哈爾濱工業(yè)大學(xué)材料科學(xué)與工程學(xué)院，哈爾濱 150001)
摘 要: 研究了SiCw/L3復(fù)合材料固相區(qū)和液-固兩相區(qū)擠壓行為，提出了包覆擠壓方法 。通過SEM、圖象分析和拉伸性能測試，對鑄態(tài)和擠壓態(tài)SiCw/L3復(fù)合材料的組織和性能進行了觀察、分析和測定。結(jié)果表明，液-固兩相區(qū)擠壓雖然有效地減輕了晶須折斷程度，卻造成了擠壓棒表面質(zhì)量的惡化；液-固兩相區(qū)包覆擠壓既有效地減輕了晶須折斷程度，又保證了擠壓棒的表面質(zhì)量。與固態(tài)擠壓相比，液-固兩相區(qū)包覆擠壓的擠壓棒強度進一步提高和塑性大幅度下降，可歸因于晶須折斷程度減輕。
關(guān)鍵字: 鋁基復(fù)合材料 液固兩相區(qū) 包覆擠壓 組織 性能
（School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001, P. R. China）
Abstract:The extrusion behavior of SiCw/L3 composite in the liquid-solid two phase region as well as the solid phase region was studied. A process of clad extrusion is presented. Experiments on the microstructure and properties of both as-cast and as-extruded composites were conducted by SEM, graph-analyzer and tensile tests. Results showed that although the extrusion in liquid-solid two-phase region helps decrease the breakage degree of whiskers effectively, the surface quality of corresponding extruded bars becomes worse; clad extrusion in liquid-solid two phase region not only decreases the breakage degree of whiskers effectively, but also guarantees the surface quality. In comparison with solid phase extrusion, the strength of extruded bars after clad extrusion in liquid-solid two phase region increases to a certain degree and the plasticity decreases greatly. This phenomenon may be explained by the decrease in the breakage degree of whiskers.
Key words: aluminium matrix composite liquid-solid two phase region clad extrusion microstructure mechanical properties
