喷射沉积SiC_P/FVS0612薄板微观组织及力学性能

Microstructure and Mechanical Properties of Spray-deposited Heat Resistant SiC_P/FVS0612 Composite Sheet

利用XRD、OM和TEM等方法研究了喷射沉积-挤压-轧制SiC颗粒增强FVS0612(SiCP/FVS0612)薄板的微观结构及力学性能。试验结果表明,制备的SiCP/FVS0612薄板具有较高的力学性能,常温下,σb=420MPa,σ0.2=405MPa,δ=4.5%;在315℃时,σb=229MPa,σ0.2=130MPa,δ=3.5%;在400℃时,σb=141MPa,σ0.2=131MPa,δ=3.3%。该复合材料在400℃退火200h,硬度没有明显下降。微观组织分析表明:类球状细小弥散的Al12(Fe,V)3Si相的生成是该材料具有优异耐热性能的主要原因,此外,SiC颗粒的加入对提高该复合材料的耐热性能也有很重要的作用。

Microstructure and mechanical properties of spray deposition-extrusion-rolling SiCP/FVS0612 composite sheet were investigated by XRD(X-ray diffraction),OM (optical microscope) and TEM(transmission electron microscope). The results reveal that tensile strength,yield strength and elongation of the prepared SiCP/FVS0612 composite sheet are 420 MPa,405 MPa,4.5%,respectively,at room temperature and 229 MPa,130 MPa and 3.5%,respectively,at 315 ℃ as well as 141 MPa,131 MPa and 3.3%,respectively,at 400 ℃,showing acceptable mechanical properties. In addition,the decrement of hardness of the composite sheet can be ignored with annealing at 400 ℃ for 200 h. Microstructural observation reveals that the desirable heat resistance is mainly attributed to the creation of fine spheroidal dispersive Al12(Fe,V)3Si phase in the composite sheet. In addition,SiC particle addition can play positive role for improvement of heat resistance of the composite sheet also.