Al_(2)O_(3)/TiB_(2)/Al复合材料的微观结构和高温力学性能  

Microstructure and Elevated Temperature Mechanical Properties of Al_(2)O_(3)/TiB_(2)/Al Composites

作　　者：汪佳 刘伟[2] 束国刚 李丘林 Wang Jia;Liu Wei;Shu Guogang;Li Qiulin(Tsinghua Shenzhen International Graduate School,Shenzhen 518055,China;School of Materials Science and Engineering,Tsinghua University,Beijing 100084,China;China Nuclear Power Engineering Co.,Ltd,Shenzhen 518172,China)

机构地区：[1]清华大学深圳国际研究生院,广东深圳518055 [2]清华大学材料学院,北京100084 [3]中广核工程有限公司,广东深圳518172

出　　处：《稀有金属材料与工程》2021年第3期787-794,共8页Rare Metal Materials and Engineering

基　　金：Science and Technology Key Project of Guangdong Province(2019B121204005)。

摘　　要：以细雾化铝粉和TiB_(2)颗粒为原料,通过粉末冶金和热轧制制备微米TiB_(2)和纳米Al_(2)O_(3)颗粒增强铝基复合材料。室温时,由于TiB_(2)和Al_(2)O_(3)的综合强化作用,Al_(2)O_(3)/TiB_(2)/Al复合材料的屈服强度和抗拉强度分别为258.7 MPa和279.3 MPa,测试温度升至350℃时,TiB_(2)颗粒的增强效果显著减弱,原位纳米Al_(2)O_(3)颗粒与位错的交互作用使得复合材料的屈服强度和抗拉强度达到98.2MPa和122.5 MPa。经350℃退火1000 h后,由于纳米Al_(2)O_(3)对晶界的钉扎作用抑制晶粒长大,强度和硬度未发生显著的降低。Aluminum matrix composites with micro-TiB_(2) and nano-Al_(2)O_(3) particles were successfully fabricated by combining powder metallurgy and hot rolling using raw materials of fine atomized aluminum powders and TiB_(2) particles.Results show that the Al_(2)O_(3)/TiB_(2)/Al composites exhibit a yield strength of 258.7 MPa and an ultimate tensile strength of 279.3 MPa at 25℃due to the comprehensive strengthening effect of TiB_(2) and Al_(2)O_(3) particles.The strengthening effect of TiB_(2) particles significantly weakens with rising the temperature to 350℃,and the Orowan strengthening mechanism between nano-Al_(2)O_(3) and dislocation makes the yield strength and tensile strength of the composite material reach 98.2 and 122.5 MPa,respectively.After annealing at 350℃for 1000 h,due to the pinning effect of nano-Al_(2)O_(3) at grain boundaries,the grains growth is suppressed significantly,and the strength and hardness do not decrease significantly.

关 键 词：TiB_(2)/Al复合材料 纳米Al_(2)O_(3) 力学性能 高温稳定性 

分 类 号：TB33[一般工业技术—材料科学与工程]