Diffusion welding of SUS304L stainless steel to titanium

The aims of this study are first to investigate the relationship between diffusion welding parameters and joint quality of SUS304L stainless steel to titanium, and secondary to develop a bonding method to get good joints using a heat treatment in a vacuum for surface control. The equipment used consists of an ultra high vacuum welding chamber and an surface analysis chamber with Auger device.The strength of joints increased using higher welding pressure and finer surface roughness at diffusion welding of SUS304L stainless steel to tianium. The heat treatment of specimens in a vacuum caused dissociation of surface oxides and contaminants. Bond formation at the contact area depended on the disappearance of the surface film.Therefore, a new bonding process where specimens were heated in a vacuum prior to bonding was developed, unlike the conventional bonding process where the joint region was heated after the bonding surfaces are brought into contact. This bonding method produced the sound joint when specimens were heated at the suitable temperature.