SiCf/Ti60复合材料预制体热等静压致密化过程数值模拟

Numerical simulation of hot isostatic pressing densification process of SiC_f/Ti60 composites prefabricated body

采用有限元方法对SiCf/Ti60复合材料预制体的热等静压致密化过程进行了模拟研究,研究分析了预制体中先驱丝排布方式、SiC纤维的体积分数和热等静压工艺参数对复合材料预制体致密化行为的影响。结果表明,SiCf/Ti60复合材料预制体在热等静压致密化过程中呈现出4个阶段特征;先驱丝堆垛排布方式对预制体的致密化行为有一定的影响,但在致密化的最后阶段,四方和六方排布方式下的致密度趋于相同;增大SiC纤维的体积分数可使热等静压前期的致密度略有增加,但使热等静压后期的致密度略有减小;增大升温速率可较显著缩短预制体完全致密化的时间,而提高升压速率仅少量增加预制体的致密度。

The hot isostatic pressing(HIP)densification process of Si Cf/Ti60 composites prefabricated body was simulated by finite element method.The effects of precursor wire arrangement mode,Si C fiber volume fraction and HIP process parameters on the densification behavior of composite prefabricated body were investigated.The results show that the Si Cf/Ti60 composites prefabricated body exhibits four stages in the process of HIP densification;the stacking arrangement mode of precursor wire has a certain influence on the densification behavior of prefabricated body,but in the last stage of densification,the density tends to be the same with square and hexagonal arrangement;increasing the volume fraction of Si C fibers can slightly increase the density in the early stages of HIP,but slightly decrease the density in the later stages of HIP;increasing the heating rate can significantly shorten the time of densification of prefabricated body,while increasing the pressure rising rate can only slightly increase the densification of prefabricated body.