热加工后SiC颗粒的分布对喷射沉积7075/SiC_p复合材料性能的影响

Effect of particle distribution on mechanical properties of multi-layer spray forming 7075/SiC_p composite after hot forming

研究了多层喷射沉积大尺寸7075/SiCp复合材料的沉积坯和挤压坯两种坯料经过循环压制加工后SiC颗粒的分布,测试了复合材料循环压制后的力学性能,通过拉伸断口SEM形貌分析了复合材料的断裂行为。结果表明:沉积坯经过循环压制后发生了SiC颗粒的破碎,但是由于塑性变形程度有限,基体依然不致密,破碎的SiC颗粒团聚在一起,复合材料的强度和伸长率都较低。挤压坯经过循环压制后SiC颗粒尺寸较小、分布均匀,复合材料性能得到提高。

Large dimensional spray formed 7075/SiCp composite and extrusion billet were densified by cyclic pressing. The distribution of SiC particles during cyclic pressing was investigated. Tbe tensile properties of the composites were tested and the fracture surface was studied by optical micrographs and SEM. The results show that the deposited and cyclic-pressed billets have low tensile strength and elongation due to pores and the cluster of SiC . After extrusion and subsequent cyclic pressing the tensile strength of the composite reaches to 640MPa due to the improved SiC particle distribution and less defect in the matrix.