SiC_p/Al-Fe-V-Si的板材成形过程中显微组织和力学性能的演变

贺毅强¹，陈振华²

(1. 淮海工学院 机械工程学院, 连云港 222005；
2. 湖南大学 材料科学与工程学院, 长沙 410082)

摘 要：采用多层喷射沉积工艺制备SiC_p/Al-Fe-V-Si复合材料，并分别通过挤压后轧制和热压后轧制工艺制备了板材，分析了复合材料不同状态下的显微组织、物相和力学性能，并研究在轧制过程中复合材料密度和硬度的变化规律。结果表明：挤压后轧制和热压后轧制均能有效致密沉积坯。与挤压后再轧制相比，热压后再轧制材料组织更均匀细小，力学性能更优秀。挤压后再轧制板材抗拉强度为535 MPa，伸长率为4.0%，压下25%前，挤压坯的密度和硬度随之降低；当压下25%时，密度和硬度升高。热压后轧制板材抗拉强度达580 MPa，伸长率达6.3%，压下量低于10%时，热压坯密度与硬度随压下量升高；压下10%至40%，密度和硬度下降；压下量高于40%后，密度与硬度升高。对于两种材料，随着压下量的增加，轧制过程中密度与硬度的变化规律都一致。

关键词：耐热铝合金；复合材料；喷射沉积；板材成形；显微组织；力学性能

Microstructure and mechanical property evolution of SiC_p/Al-Fe-V-Si composite during sheet forming process

HE Yi-qiang¹, CHEN Zhen-hua²

(1. College of Mechanical Engineering, Huaihai Institute of Technology, Lianyungang 222005, China;
2. College of Materials Science and Engineering, Hunan University, Changsha 410082, China)

Abstract:SiC_p/Al-Fe-V-Si composite prepared by multi-layer spray deposition was densified by rolling process after extruding and rolling after pressing. The microstructure, phases and mechanical properties of the composite under different conditions were analyzed. And the density and hardness evolution of the composite during rolling process were investigated. The results show that the composite deposits can be densified and strengthened efficiently by rolling processes after extruding and pressing separately. More homogeneous, finer microstructure and more excellent mechanical properties of the composite are obtained by rolling process after pressing than by rolling process after extruding. The tensile strength and elongation of the composite as-rolled after extruding are 535 MPa and 4.0%, both of hardness and density of the composite as-extruded decrease firstly when reduction is below 25% and then raise during rolling process, which agrees with density evolution. The tensile strength and elongation of the composite as-rolled after pressing are 580 MPa and 6.3%. And those of the as-pressed composite firstly when reduction is below 10%, then decrease until the reduction reaches 40%, and finally rise during rolling process. The hardness varies as density does with reduction increases during rolling process for both of the composites.

Key words:heat resistant alloy; spray deposition; composite; sheet forming; microstructure; mechanical property