TiC-TiB_2/Cu复合材料的自蔓延高温合成研究

Self-propagating High-temperature Synthesis of TiC-TiB_2/Cu Ceramic-matrix Composite

采用SHS/PHIP工艺制备了TiC-TiB_2/Cu复合材料,通过实验研究了该系列复合材料的微观结构特征和力学性能。结果表明,TiC-TiB_2/Cu复合材料中只有TiC、TiB_2和Cu相存在;随着Cu含量的增加,燃烧温度下降,材料的颗粒尺寸变小;TiC-TiB_2/Cu复合材料的相对密度、抗弯强度和断裂韧性均随Cu含量的增加呈先增后减趋势,当Cu含量为20％时强度最高为580MPa,Cu含量为40％时韧性最高为8.1MPa·m^(1/2)。

TiC-TiB2/Cu ceramic-matrix composites were produced by self-propagating high-temperature combustion synthesis combined with pseudo hot isostatic pressing. Microstructure and mechanical properties of the synthesized compacts were investigated. The results show that the final product consists of TiC, TiB2 and Cu three phases, which is pure without unreacted B4C and Ti. The particle size of TiB2 and TiC decreases with Cu content increasing due to the reduction of the combustion temperature. The introduction of Cu into TiB2-TiC/Cu composites results in a drastic increase in the relative densities, transverse rupture strength and fracture toughness. The maximum bend strength obtained with the addition of 20wt% Cu is 580MPa, while the maximum fracture toughness obtained with the addition of 40wt% Cu is 8.1MPa.m(1/2).