Mo-Ti系复合材料的特性波阻抗

Characteristic Wave Impedance of Mo-Ti Composites

采用放电等离子烧结技术 ,在相同的温度 (14 73K)及压力 (30 MPa)下 ,制备出不同配比的致密的 Mo- Ti系复合材料。采用高精度超声波脉冲回波重合法 ,精确测量了样品的横、纵波声速 ,并由此计算得到其特性波阻抗的实验值。对样品的相组成分析及电子探针分析的结果表明 ,Mo- Ti系复合材料是通过 Mo和 Ti之间形成固溶体来实现烧结致密化的。选用混合物模型对其特性波阻抗值进行了理论预测 ,与实测值的比较表明该模型能对 Mo-

Dense Mo Ti composites with different weight fractions of Mo and Ti were prepared at the same temperature (1 473 K) and pressure (30 MPa) by using spark plasma sintering technique. The transverse and longitudinal wave velocities of the samples were accurately measured using the ultrasonic pulse echo overlap method, by which the characteristic wave impedance values of the samples were then obtained. The analyzing results of phase composition and electron probe microscope analysis show that the formation of Mo Ti solid solution contributes to the sintering densification of Mo Ti composites. The mixture model was adopted to estimate the characteristic wave impedance of Mo Ti composites in this paper. Comparisons with the experimental results demonstrate that the suggested model is sufficiently accurate to predict the wave impedance value of Mo Ti composites.