B_4C(W,Ti)C陶瓷复合材料的制备及其性能

Preperation of B_4C/(W,Ti)C Ceramic Composite and Study on Its Mechanical Properties

采用热压烧结工艺制备了B4 C/(W ,Ti)C陶瓷复合材料。研究表明 :B4 C/(W ,Ti)C陶瓷材料烧结时将产生化学反应 ,反应产物为TiB2 和W2 B5。B4 C/(W ,Ti)C陶瓷材料的性能与 (W ,Ti)C的含量密切相关 ,随 (W ,Ti)C含量的增加 ,材料的致密度、抗弯强度和断裂韧性逐渐增加 ,硬度逐渐减小 ;当保温时间低于 5 0min时 ,材料的致密度、抗弯强度和硬度显著降低 ;B4 C/(W ,Ti)C陶瓷复合材料的最佳性能参数为 :抗弯强度 6 93MPa ,维氏硬度 2 3.5GPa ,断裂韧性 3 .9MPa·m1/2 。磨损实验表明 ,B4 C/(W ,Ti)C陶瓷材料在低速小载荷的实验条件下 ,耐磨性能优异 ,在高速大载荷的实验条件下 ,磨损过程中局部点的高温导致试样表面发生氧化 。

In this study,B 4C/(W,Ti)C ceramic composites were prepared using hot pressing technique.Chemical compatibility calculation and XRD analysis proved that chemical reaction would take place for this ceramic material system during hot pressing sintering.Under the optimum conditions,the flexural strength of this material is 693MPa,vickers hardness 23.5GPa,and fracture toughness 3.9MPa·m 1/2 .The effects of soaking time and mass content of(W,Ti)C on the mechanical properties were investigated.The wear -resistant test indicated that the loss in volume increased at high speed and heavy loading conditions for B 4C/(W,Ti)C ceramic composites.