Effects of gravitational orientation on gas tungsten arc (GTA) welding of nickel were studied to determine the impact of free-surface deformation on weld-pool shape. This was accomplished through GTA welding and a numerical study of the welding process. Welding was conducted by varying scan velocity and gravitational orientation, e.g., welding upward opposing gravity (parallel-up weld), welding downward with gravity (parallel-down weld), and welding perpendicular to gravity (perpendicular weld). Slower scan velocity produced more significant free surface deformation. Gravitational orientation caused 21% deeper penetration in the parallel-up weld compared with the parallel-down weld (resulting from 50% or more maximum surface deformation). Weld penetration of the perpendicular weld was between that of parallel-up and parallel-down cases. A model of the welding process, in which an experimentally generated free surface was implemented as a boundary condition, supported the results by showing similar trends.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering
- Industrial and Manufacturing Engineering