摘要
A bypass-current metal inert-gas welding-brazing technology has been developed to join aluminum/galvanized steel and aluminum/stainless steel. Microstructure, intermetallic compounds and hardness distribution of the joints were studied by optical microscopy, scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction analysis and microhardness tests. Comparative study on both types of joints was carried out. During aluminum to galvanized steel assembling, finer seam was obtained under a more stable process. A uniform interfacial reaction layer with a thickness of 2-4 μm was formed. During aluminum to stainless steel assembling, an uneven interfacial reaction layer with a thickness of 5-45μm was formed. Intermetallic compounds at the interface of aluminum/galvanized steel were identified as Fe-Al- Si-Zn complex phases, while Fe-Al-Cr-Ni complex phases were found at the aluminum/stainless steel interface. Microhardness of interfacial layer increases rapidly within reaction layer due to possible brittle intermetallic compounds.
A bypass-current metal inert-gas welding-brazing technology has been developed to join aluminum/galvanized steel and aluminum/stainless steel. Microstructure, intermetallic compounds and hardness distribution of the joints were studied by optical microscopy, scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction analysis and microhardness tests. Comparative study on both types of joints was carried out. During aluminum to galvanized steel assembling, finer seam was obtained under a more stable process. A uniform interfacial reaction layer with a thickness of 2-4 μm was formed. During aluminum to stainless steel assembling, an uneven interfacial reaction layer with a thickness of 5-45μm was formed. Intermetallic compounds at the interface of aluminum/galvanized steel were identified as Fe-Al- Si-Zn complex phases, while Fe-Al-Cr-Ni complex phases were found at the aluminum/stainless steel interface. Microhardness of interfacial layer increases rapidly within reaction layer due to possible brittle intermetallic compounds.
基金
supported by the National Natural Science Foundation of China (No. 51005049)
