Ti,B 化合物制取颗粒增强 TiB_2/Al 复合材料

PARTICULATE REINFORCED TiB 2/Al COMPOSITE PREPARED USING Ti,B COMPOUND

用熔炼法制备ＴｉＢ２／Ａｌ复合材料．通过添加Ｔｉ，Ｂ化合物，在纯铝基体中原位生成ＴｉＢ２颗粒，基体得以增强．就ＴｉＢ２的体积分数对复合材料机械性能和显微组织的影响进行了研究，并对两种Ｔｉ，Ｂ化合物（Ⅰ，Ⅱ号）的增强效果进行了比较．结果表明，ＴｉＢ２／Ａｌ复合材料的机械性能明显优于铝基体．与Ⅰ号Ｔｉ，Ｂ化合物相比，Ⅱ号Ｔｉ，Ｂ化合物能更有效地提高复合材料的强度和硬度．ＴｉＢ２／Ａｌ复合材料的拉伸强度和硬度随Ｔｉ，Ｂ化合物加入量增多而提高，而延伸率降低．含２．０％（体积分数）ＴｉＢ２的复合材料其热轧退火态的拉伸强度和铸态布氏硬度分别为１５８ＭＰａ和３８８ＭＰａ，与纯铝基体相比，拉伸强度和硬度分别提高了１１１％和５１％．

TiB 2/Al composites were fabricated by casting in the present work.When Ti,B compounds were added to pure aluminum,aluminum matrix were reinforced due to the formation in situ of TiB 2 particles in the aluminum matrix.Effects of volume fraction of TiB 2 on mechanical properties and microstructure of composites were studied,and the reinforced efficiency of two Ti,B compounds (Ⅰ and Ⅱ)were compared.The results indicated that the mechanical properties of TiB 2/Al composites were superior to aluminum matrix.Ti,B compound Ⅱ reinforcement was more effective than Ti,B compound Ⅰ in increasing the strength and hardness of the composite.Tensile strength and hardness of TiB 2/Al composites increased with increasing amounts of Ti,B compound,but elongation decreased.In the case of 2 0%(volume fraction) TiB 2/Al composite,tensile strength as hot rolling and annealed and Brinell hardness as cast were 158 MPa and 388 MPa respectively.As compared with pure aluminum matrix,the tensile strength and hardness increased by 111% and 51% respectively.