(1. 上海交通大學(xué) 材料科學(xué)與工程學(xué)院，凝固科學(xué)與技術(shù)研究所，上海 200240；
2. 上海市先進(jìn)高溫材料及其精密成型重點(diǎn)實(shí)驗(yàn)室，上海 200240)
摘 要: 利用高能球磨結(jié)合放電等離子體燒結(jié)和熱擠壓工藝，制備出TiB2/Al-3.8Zn-1.85Mg-1.32Cu復(fù)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(xué)性能測試，研究TiB2顆粒添加量對復(fù)合材料微觀組織和力學(xué)性能的影響。結(jié)果表明：高能球磨誘導(dǎo)TiB2陶瓷顆粒形貌從多邊形轉(zhuǎn)變?yōu)榻蛐危浑S著TiB2含量從2%增加到10%(體積分?jǐn)?shù))，鋁基體晶粒逐漸細(xì)化，析出相含量減少，復(fù)合材料抗拉強(qiáng)度、屈服強(qiáng)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(xì)晶強(qiáng)化和彌散顆粒強(qiáng)化為復(fù)合材料的主要強(qiáng)化機(jī)制。
關(guān)鍵字: 鋁基復(fù)合材料；TiB2增強(qiáng)相；粉末冶金；微觀組織；力學(xué)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
