包覆层浇注温度对铝/钢液-固复合组织及性能的影响OA

Using 304 stainless steel and pure aluminum as test materials,the aluminum/steel bimetallic composite materials were prepared via liquid-solid composite casting technology and a self-designed pouring system.The surface of 304 stainless steel was pretreated by nickel plating,and the effects of pure aluminum pouring temperatures(750,780,810℃)on microstructure,composition,and mechanical properties of aluminum/steel composite interface were studied using SEM and XRD.The results show that the microstructure of the diffusion layer of aluminum/nickel plated steel is significantly improved,compared with that before nickel plating.The nickel coating can improve the surface activity and wettability of aluminum liquid on the steel substrate.As the pouring temperature increases,the shear strength and thickness of diffusion layer increase.The aluminum/steel has the best bonding quality at pouring temperature of 810℃,with no defects such as inclusions or pores in the diffusion layer,and the average shear strength of the composite interface is up to 25.78 MPa.The microhardness of the aluminum/steel diffusion layer increases first and then decreases with the increase of pouring temperature.At the pouring temperature of 780℃,the microhardness of the diffusion layer reaches a maximum of about HV1 000.