Microstructure and Wear Behavior of the High‐Velocity‐Oxygen‐Fuel Sprayed and Spark Plasma Sintered High‐Entropy Alloy AlCrFeCoNi
Martin Löbel, Thomas Lindner, S. Clauss, Robert Pippig, D. Dietrich, Thomas Lampke
Abstract
High‐entropy alloy AlCrFeCoNi powder with a metastable body centered cubic (bcc) structure is produced by inert gas atomization. This state is largely preserved after processing the powder by high‐velocity‐oxygen‐fuel (HVOF) thermal spraying. A heat treatment is conducted with the objective to form a duplex structure comprising a ductile face centered cubic (fcc) phase. The formation of an additional fcc phase is accompanied by a decrease in hardness and a significant improvement of wear resistance. The alternative processing route, spark plasma sintering (SPS), causes a duplex bcc and fcc structure. Detailed analyses of phase formation and wear behavior for all production routes contribute to a better understanding of microstructural effects in high‐entropy alloys.