C/SiC/Si-Mo-Cr复合涂层碳/碳复合材料力学性能研究

Mechanical Properties of C/SiC/Si-Mo-Cr Multilayer Coated Carbon/carbon Composites

采用包埋法和涂刷法在碳/碳复合材料表面制备了一种新型的C/SiC/Si-Mo-Cr复合高温抗氧化涂层.借助XRD和SEM等测试手段对所制备复合涂层的微观结构进行了表征,采用三点弯曲试验研究了涂层处理及热震试验对碳/碳复合材料力学性能的影响规律。结果表明:制备的多相涂层结构致密,涂层后碳/碳复合材料弯曲强度有所增大,断裂特征由假塑性向脆性转变.涂层试样经1500℃至室温20次热震后,涂层试样的弯曲强度降低,塑性增强.

A novel C/SiC/Si-Mo-Cr multilayer oxidation protective coating for carbon/carbon composites was prepared by pack cementation and slurry method. The microstructures of the as-prepared multilayer coating were characterized by XRD and SEM analyses. The effects of the coating processing and thermal shock on the mechanical properties of carbon/carbon composites were investigated by three point bending tests. The results show that the as-obtained multiphase coating is dense, and the flexural strength of carbon/carbon composites after coating increases and the fracture behavior changes from the pseudo-plastic fracture to brittle fracture mode. After enduring the thermal cycling between 1500℃ and room temperature for 20 cycles, the flexural strength of the coated specimens decreases accordingly, and the plastic increases.