The process and mechanical properties of GH4169 columnar crystals fabricated by wire arc additive manufacturing

Abstract

Wire- Arc Additive manufacture (WAAM) has been widely applied in metal field to control metal structure and microstructure. GH4169 is well fit to the WAAM due to its excellent weldability. While the columnar crystal has greater growth advantage than equiaxed crystal, so the superalloy GH4169 whose grain boundary induce its high temperature mechanical property will have fewer boundaries that can increase the property. While the shape of AM sample can be controlled, growth direction of columnar crystal can be adjusted through the heating method. If t growth directions of columnar crystals are consistent, the number of grain boundaries well induce largely. We can use different heating method and compare the result of growth direction. While the temperature environment at the top which decides the growth direction fit the requestion of growth direction, we can get the columnar that grows as we design.