Additive Manufacturing of Titanium and Nickel-Based Alloys Using Arc Welding and VHP UAM

Processes such as laser additive manufacturing (LAM) and electron beam additive manufacturing (EBAM) using various methods of material delivery, such as wire feed and powder beds are well known and moving along a path to flight qualification.  Other additive processes, such as arc welding additive manufacturing (AWAM), or very high power ultrasonic additive manufacturing (VHP/UAM), are being studied but further behind in the five steps (established through the Air Force and MAI) on the path to full flight qualification.  The available AM processes range from those producing very fine detail part features at deposition rates as low as 20 hrs/lb, to those producing large deposits at 20 lbs/hr, or more.  There is a lot of ‘trade space’ in between that has really not been explored to a significant degree.  This presentation summarizes work conducted using arc welding processes and VHP/UAM for common titanium and nickel based alloys.  Arc Welding processes addressed include gas tungsten arc welding with hot wire feed (GTAW-HW) plasma arc welding (PAW) and variants of gas metal arc welding (GMAW), including pulsed (GMAW-P) and reciprocating wire feed GMAW (RWF-GMAW).  The former arc welding processes, with suitable inert gas shielding, offer the opportunity to meet property requirements at much more affordable cost than offered by EB and LAM.

VHP/UAM is a new, higher power, version of the UAM process providing up to 6 times more power and ten times more down force than offered by present commercially available equipment.  The VHP UAM process is being commercialized at present and also being evaluated for nickel and titanium alloys as well as aerospace aluminum alloys.  This presentation will summarize the current state of the art for this new variant of the UAM process.