为了改善复合材料的力学性能,对2200℃热压烧结后的20vol%ZrCp/W复合材料进行了高温退火处理,退火工艺为2300℃×60min。结果表明,高温退火后,复合材料几乎达到了完全致密化,W2C相的生成量增多,复合材料中的缺陷减少,ZrC颗粒和W的晶粒尺寸增大。复合材料的弹性模量和维氏硬度变化很小,断裂韧性略有增大,而抗弯强度则急剧下降,这可能与晶粒尺寸增大和杂质元素在晶界的偏聚有关。
To improve the mechanical properties, the annealing process at 2300℃ for 60min was applied to 20vol% ZrCp/W composite prepared by hot pressing at 2200℃. The microstructure and mechanical properties of the annealed composite were investigated. The result shows that the annealing treatment enables the 20vol% ZrCp/W composite to achieve almost full densification. In addition, content of W2 C phase increases and defects decrease in the composite after annealing treatment. Meanwhile, both the ZrC particles size and W grain size increase. The elastic modulus and Vickers hardness change a little and the fracture toughness of the composite increase slightly. However, the flexural strength of the composite tends to decrease sharply, which can be attributing to grain growth and segregation of impurity in grain boundary during the annealing treatment.