浸渗法制备双连续TiB_2/(Cu,Ni)复合材料的组织和性能

Research on properties and microstructure of TiB_2/(Cu,Ni) interpenetrating phase composites by melt infiltration

用高温粉末烧结结合自发浸渗法制备高TiB2含量(体积含量约为86%)的双连续TiB2/(Cu,N i)复合材料,研究了不同陶瓷体积含量多孔材料对TiB2/(Cu,N i)复合材料微观组织和力学性能的影响.采用XRD和SEM分析了复合材料的相组成和微观结构,用三点弯曲试验测试了复合材料的弯曲强度和断裂韧性.结果表明:经过预制坯高温烧结后自发熔渗金属是制备致密的双连续TiB2/(Cu,N i)复合材料的有效方法,复合材料的致密度和力学性能得到显著提高;当TiB2陶瓷体积含量为81.6%以及浸渗温度为1500℃条件下,TiB2/(Cu,N i)复合材料的弯曲强度和断裂韧性分别达到640.5 MPa和9.37 MPa.m1/2,相对密度为98.4%.

TiB2/（ Cu, Ni） interpenetrating phase composites （IPCs） with ceramic content of 75% - 86% are prepared by high-temperature powder sintering and subsequently melt infiltration. The microstructure and mechanical properties of the TiB2/（Cu, Ni） IPCs with different TiB2 ceramic volume contents are investigated detailedly. The phase constitution and microstructures are studied by SEM and XRD. The bending strength and fracture toughness are also investigated by three-point bending tests. The results show that high temperature sintering of pre-pressed compact combined with subsequently melt infiltration is a good way to fabricate TiB2/ （Cu, Ni） interpenetrating phase composites. Mechanical properties and densities are improved observably. The bending strength and fracture toughness attain 640. 5 MPa and 9. 37 MPa · m^1/2, and the relative density reaches 98.4% with the infiltration temperature of 1500 ℃ and the ceramic volume content of 81.6%.