Processing of reactive Ni−Al powders via the LabRAM**

Abstract

Reactive Ni−Al materials have been developed using a variety of methods, with high energy ball milling (HEBM) being one of the most common means for tailoring reaction behavior. Powder production limitations associated with HEBM, including the addition of process control agents, have inspired the exploration of an alternate manufacturing technique: acoustic dry milling with the Resodyn Laboratory Resonant Acoustic Mixer (LabRAM). The influence of acoustic milling time, intensity, and media size with respect to microstructure and reactive behavior of Ni−Al powders were evaluated in this work. After just 20 min of milling, a reactive composite Ni−Al microstructure was produced. Milling intensity and media size were directly proportional to the formation of more homogeneous composite powders. The reaction onset temperature was decreased to 446 °C, or ≈200 °C lower than that of unprocessed material. The method shows promise for the production of reactive powder for a host of applications.