Interfacial mechanical property of steel-mushy Al-20Sn bonding

The bonding of a steel plate to Al-20Sn slurry was conducted using the casting rolling technique. The surface of the steel plate was defatted, descaled, immersed (in K₂ZrF₆ flux aqueous solution) and stoved. Al-20Sn slurry was prepared using the electromagnetic mechanical stirring method. The interfacial mechanical property of the bonding plate was researched to determine the relationship between the diffusion time and the interfacial shear strength. In order to identify the mechanism of bonding, the interfacial structure of the bonding plate was studied. The results show that at a preheat temperature of the steel plate of 505℃ and a solid fraction of Al-20Sn slurry of 35%, the relationship between the interfacial shear strength S and the diffusion time t is S=28.8+4.3t-0.134t² +0.0011t³. When the diffusion time is 22 s, the largest interfacial shear strength is 70.3 MPa, and the corresponding interface is a new one which is made up of Fe-Al compound and Fe-Al solid solution alternatively and in a right proportion.In this interfacial structure, the interfacial embrittlement does not happen and Fe-Al compound can play its role in strong combination adequately.