TWI Industrial Member Report Summary 236/1984
By W M Thomas, E D Nicholas and S B Dunkerton
Background
The use of frictional energy to deposit metals in the solid phase on a substrate has been briefly highlighted in the literature over the last 20 years. However, a systematic evaluation of its feasibility for industrial exploitation has not been undertaken. Thus, with this ultimate goal in mind, a series of trials were carried out to obtain a better understanding of the relationships between welding parameters and deposit characteristics viz, bond integrity, deposit thickness and width and finally deposition rate. To pursue these aims it was first of all necessary to design and construct a traverse system which when interfaced with a conventional friction welding machine would provide a means of moving the substrate across the face of a rotating consumable. Experiments using a 25mm diameter mild steel consumable bar demonstrated that deposit thicknesses and widths of approximately 2 and 20mm respectively could be placed on a 0.4%C, Ni, Cr, Mo steel substratate traverse rates within the range 2.5 to 12mm/sec. Multilayer deposits were also found to be possible although some problem areas were identified. Brief trials demonstrated that both stainless steel and Inconel 600 could be deposited on mild steel. In contrast, however, no success was achieved when attempting to deposit pure aluminium on mild steel and copper on stainless steel.