Analysis of factors affecting the automatic high-frequency induction brazing strength of PDC

With the development of automation and intelligentization in manufacturing industry, the research on PDC bit brazing automation is one of the key development directions of bit production technology. In order to study the influencing factors and adaptation methods of welding strength in PDC automatic brazing process, PDC high frequency induction welding and shear strength comparison test were carried out by using PDC and alloy pillar as the base material through special tooling and test conditions. Combined with the shear strength experiment and the morphology of brazing surface of PDC high-frequency induction brazing, the effect of brazing filler alloys, fluxes, surface pretreatment, welding method, heat preservation and induction heating on welding strength was analyzed, and a brazing process suitable for PDC automatic brazing was proposed. The results showed that the suitable silver brazing filler alloys and special solder paste should be selected according to the actual situation; the surface oxide layer of the base metal has a great influence on the brazing strength; the rotary auxiliary welding method is helpful for the spreading of the solder and the exhaust slag, at the same time, this method can effectively improve the strength of induction brazing; the heat preservation has little effect on induction brazing strength of PDC; the influence of skin effect on the edge solder melt while the center solder not melt because of the low temperature should be reduced, which would affect the strength of the work piece.The research results provide a feasible solution for the realization of PDC automatic induction welding, and provide a basis for the realization of PDC bit automatic brazing.