Wire Arc Additive Manufacturing of creep strength enhanced ferritic steels and Nickel alloys

Additive manufacturing – popularly known as 3D printing – is one of the most revolutionary manufacturing methods. It not only allows almost lossless processing of high-value material but also results in high-demanding components with a flexibility that would not be conceivable using conventional methods. Wire Arc Additive Manufacturing (WAAM) which is one of the most efficient additive manufacturing technologies is based on a conventional welding process like GMAW which is fully automated and guided by CAD/CAM on robotic or CNC welding systems.

This paper deals with principal concepts and metallurgical features behind WAAM. The main part attention is drawn to the mechanical properties of printed sample structures made from P91, X20, alloys 625 and 718 wire feedstock. Especially the questions on anisotropy of mechanical properties are addressed by short and long-term testing and are compared to conventional processed material.