Research on 16Mo3 steel pipe overlaid with superalloys Inconel 625 using robotized PPTAW

Abstract

The article presents research on the development of technology and mechanical properties of a 16Mo3 steel tube overlaid with Inconel 625 nickel superalloy using robotized Plasma Powder Transferred Arc Welding (PPTAW) process. Based on the results of non-destructive, metallographic and microscopic observations, chemical composition, thickness and hardness measurements of overlays optimal technological parameters for working in elevated temperature environment were selected. The performedtest has shown the correct structure of the overlay weld without welding imperfections. The examined padding weld was characterized by a dendritic structure with primary crystals growing in the direction of heat removal. It has been stated that in the range of heat input to base material 277÷514 J/mm, the iron content in the surface zone of 1,5 mm padding weld ranges from 4 to 5,5%. od 4 do 5,5%.