The influence of manufacturing process on the fundamental properties of NiCoCrAlY powder

The specific requirements of powder materials depend on the service environments. However, the fundamental characteristics of powders are primarily determined by manufacturing processes. As a high-performance nickel-based superalloy powder, NiCoCrAlY has been widely used in the additive manufacturing, laser cladding, thermal spray coatings, and powder metallurgy. Based on the major powder production techniques, this study investigated the effects of plasma rotating electrode process (PREP), vacuum gas atomization (VGA), and agglomeration-sintering methods on the basic characteristics of NiCoCrAlY powders, including the particle shape, particle size, porosity, and oxygen content. The results indicated that powders prepared by the plasma rotating electrode process exhibited the most regular particle shape, the best distribution of particle size, and the lowest oxygen content and porosity, making them highly suitable for the high-precision additive manufacturing and high-performance coatings. Powders produced by the vacuum gas atomization showed a relatively uniform particle size but contained a small fraction of non-spherical particles. The oxygen content and porosity were slightly higher, making them more suitable for large-scale industrial applications. In comparison, powders produced by the agglomeration-sintering exhibited a moderate porosity but a strikingly uneven distribution of particle size and an extremely high oxygen content, putting their applications only in where low-quality requirements and the cost control are prioritized, such as the production of large-particle powders or composite powders. This study aimed to provide a reference for the rational selection and further optimization of NiCoCrAlY powder production techniques based on specific application requirements.