Controlling the properties of additively manufactured alloys by feedstock modification

Additive manufacturing (AM) techniques, such as laser powder bed fusion (LPBF), are gaining popularity and have the potential to replace conventional manufacturing methods in many applications. The properties of metallic materials produced by AM depend on several factors, including the specific AM technique, processing parameters, build environment, and the feedstock used. Selecting an appropriate feedstock can be an effective strategy to enhance material properties and reduce sensitivity to processing parameters. In this work, examples of stainless steel, copper, and aluminum alloys are considered, in which the feedstock was modified by adding selected additives via ball milling, and test coupons were subsequently produced by LPBF of the modified feedstock. Corrosion tests were carried out in NaCl solution using cyclic potentiodynamic polarization and electrochemical impedance spectroscopy. The corrosion resistance of the produced alloys depended on the type of additive used. The materials were characterized using scanning and transmission electron microscopy, which revealed that the unique microstructures induced by the additives play a critical role in determining corrosion resistance. The role of additives in microstructural evolution and corrosion behavior will be discussed