激光熔化沉积(TiB+TiC)/TA15原位钛基复合材料的显微组织与力学性能  

Microstructure and mechanical properties of laser melting deposited(TiB+TiC)/TA15 in situ titanium matrix composites

作　　者：于翔天[1] 王华明[1] 

机构地区：[1]北京航空航天大学材料科学与工程学院激光材料制备与成形实验室,北京100083

出　　处：《复合材料学报》2008年第4期113-118,共6页Acta Materiae Compositae Sinica

基　　金：国家重点基础研究发展计划(2006CB605206-2);国家杰出青年科学基金(50625413)

摘　　要：利用激光熔化沉积工艺制备了TiB+TiC增强相体积分数分别为9%、11%、22%及57%的4种(TiB+TiC)/TA15原位钛基复合材料。随增强相含量提高,TiB形态由片层状向棱柱状转化,TiC形态由不规则颗粒状向枝晶状转化,钛基复合材料硬度及弹性模量均显著提高而塑性明显下降。增强相体积分数约为9%的复合材料表现出较好的综合力学性能,增强相体积分数大于11%后复合材料的抗拉强度急剧降低。与激光熔化沉积态TA15钛合金相比,TiB+TiC增强相体积分数约为9%的复合材料抗拉强度(1040 MPa)及屈服强度(935 MPa)均提高约12%。（TiB＋TiC）/TA15 in situ titanium matrix composites with 90%, 11%, 22% and 57% volume fractions of TiB＋TiC reinforcements, respectively were fabricated by the laser melting deposition manufacturing process. The morphology of TiB changes from plate like to prismatic while the morphology of TiC evolves from particle like to dendritic with the increasing volume fraction of the reinforcements. The Rockwell hardness and elastic modulus of the composites increase and the ductility decreases with the increasing volume fraction of TiB＋TiC reinforcements. The composite with a reinforcement volume fraction of 9% exhibits the optimum mechanical properties, while the tensile strength of the composites decreases abruptly when the reinforcement volume fraction is up to approximately 11%. The yield strength （935 MPa） and ultimate tensile strength （1040 MPa） of the laser melting deposited in situ （TiB＋TiC）/TA15 composite containing 9% volume fraction of TiB＋TiC reinforcements are both enhanced by 12% compared to the as-laser deposited titanium alloy TA15.

关 键 词：激光熔化沉积 钛基复合材料 TiB TIC 显微组织 力学性能 

分 类 号：TB333[一般工业技术—材料科学与工程] TG113[金属学及工艺—物理冶金]