Influence of powder mixing method on properties of high entropy alloys of FeCrMnAlMo thin coatings obtained by magnetron sputtering
Résumé
High Entropy Alloys of FeCrMnAlMo thin coatings obtained by magnetron sputtering were studied. The influence of the powder mixing method to obtain the targets used in the physical vapor deposition reactors was evaluated concerning the mechanical and tribological properties of the coatings. The microstructural characterization was also performed. The high purity element powders of 34Fe-22Cr-19Mn-19Al-6Mo were mixed in two ways: mechanically alloyed for 35 h (MS coating) and the other by conventional mixing for 30 min (CM coating). The coatings showed a poorly crystallized structure, almost amorphous. X-ray photoelectron spectrometry results evidenced that the MS coating contains approximately 8 at.% C, while no carbon was detected in the CM coating. The coatings presented hardness values determined by nanoindentation of ~8.7 GPa and 7.4 GPa for MS and CM coatings, respectively. A better reciprocating dry sliding wear resistance with specific wear rate (k) of ~3.33 × 10−5 mm3 N−1 m−1 for MS coating/substrate system was found, while for the CM coating/substrate system was of ~8.23 × 10−5 mm3 N−1 m−1. The abrasive wear mechanism was observed with the formation of ploughing, scratching and debris wear adhered to the alumina counterpart ball.
Origine : Fichiers produits par l'(les) auteur(s)