一种反应材料制备及准静态力学特性研究

Preparation and Quasi-Static Mechanical Properties of a Reactive Material

采用热压烧结法制备Zr/W/PTFE反应材料,利用扫描电镜和材料试验机研究其在常态下的微观组织和准静态压缩力学性能;研究结果表明烧结温度过高或过低都会导致Zr/W/PTFE材料密度和强度降低;静态压缩曲线呈现出明显的弹性变形、非弹性变形和应变软化阶段,并具有应变率效应;试件的压缩破坏有劈裂、剪切和劈裂/剪切3种破坏形态.该材料呈现出黏弹塑性,采用修正的Sargin模型唯象地建立了材料在低应变率范围内的本构模型,模拟结果与实验曲线符合较好.

The Zr/W/PTFE reactive material was sintered by hot-pressing, the microstructure photos and the quasi-static compression mechanical properties were investigated experimentally using SEM and MTS at room temperature. Results show that the density and strength of Zr/W/ PTFE material will reduce when the sintering temperature is too high or too low. The quasi- static compression curves can be broadly divided into elastic deformation region, inelastic deformation region and strain softening region, and also demonstrate a distinct strain rate effect in the material. The specimens display three kinds of fracture modes, the splitting failure, the shear failure and the splitting/shear failure under the static compressive load. According to the failure strength with strain rate and visco-elastoplasticity, a modified Sargin constitutive model of the material at low strain rate was proposed. The simulation results of the constitutive model well accord with the experimental results.