自蔓延原位合成TiC/MoSi_2复合材料及其力学性能

Mechanical Properties of TiC/MoSi_2 Composites Prepared by Self-propagating In-situ Synthesis

以钼、硅、钛和碳粉为原料,采用自蔓延原位合成技术制备了不同体积分数TiC强韧化的MoSi2基复合材料,研究了TiC颗粒对MoSi2基体材料显微组织和力学性能的影响。结果表明:TiC颗粒均匀分布于MoSi2基体中;TiC体积分数为30%时,TiC/MoSi2复合材料硬度、抗弯强度和断裂韧度分别达到15.02 GPa、366 MPa和6.26 MPa.m1/2,比纯MoSi2分别增加61.5%、26.8%和150%;复合材料的断口表现为沿晶断裂和准解理断裂的混合形式,其强化机制是细晶强化和弥散强化,韧化机制为细晶韧化。

TiC/MoSi2 composites with different volume fraction of TiC particles were fabricated by self-propagating high temperature synthesis(SHS) with Mo,Si,Ti and C powders as raw materials.Effects of TiC particles on microstructure and mechanical properties of MoSi2 matrix were investigated.The results indicated that TiC particles were uniformly distributed in MoSi2 matrix.The hardness,flexure strength and fracture toughness of 30% TiC/MoSi2 composite reached 15.02 GPa,366 MPa and 6.26 MPa·m1/2 and increased 61.5%...