(1. 上海交通大學 材料科學與工程學院，凝固科學與技術研究所，上海 200240；
2. 上海市先進高溫材料及其精密成型重點實驗室，上海 200240)
摘 要: 利用高能球磨結合放電等離子體燒結和熱擠壓工藝，制備出TiB2/Al-3.8Zn-1.85Mg-1.32Cu復合材料。通過X射線衍射、掃描電鏡和透射電鏡表征以及拉伸力學性能測試，研究TiB2顆粒添加量對復合材料微觀組織和力學性能的影響。結果表明：高能球磨誘導TiB2陶瓷顆粒形貌從多邊形轉變?yōu)榻蛐危浑S著TiB2含量從2%增加到10%(體積分數(shù))，鋁基體晶粒逐漸細化，析出相含量減少，復合材料抗拉強度、屈服強度和彈性模量分別由381 MPa、231 MPa和78 GPa增加到679 MPa、645 MPa和96 GPa，伸長率從5.2%下降到1.0%；細晶強化和彌散顆粒強化為復合材料的主要強化機制。
關鍵字: 鋁基復合材料；TiB2增強相；粉末冶金；微觀組織；力學性能
（1. Institute of Solidification Science and Technology, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;
2. Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming, Shanghai 200240, China）
Abstract:TiB2/Al-3.8Zn-1.85Mg-1.32Cu composites were prepared by high energy ball milling in combination with spark plasma sintering and hot extrusion. The materials were analyzed by X-ray diffraction, scanning electron microscope, transmission electron microscope and tensile testing machine to investigate the effects of TiB2content on microstructure and mechanical properties. The results show that the morphology of TiB2 particles changes from polygon to nearly spherical as a result of high energy ball milling. With increasing TiB2 content from 2% to 10% (volume fraction), the grain size of aluminum matrix gradually is refined and the precipitates density decreases; the tensile strength, yield strength and elastic modulus of the composites increase from 381 MPa, 231 MPa and 78 GPa to 679 MPa, 645 MPa and 96 GPa, respectively, and the elongation to fracture decreases from 5.2% to 1.0%. Fine grain strengthening and dispersion strengthening are the main strengthening mechanisms.
Key words: Al-based composites; TiB2 particles; powder metallurgy; microstructure; mechanical property
