Évolution de la microstructure lors du traitement thermique de l’acier inoxydable AISI 410

Abstract

In this research work, the influence of the various parameters on the phenomena which occur during the austenitization and the tempering of AISI 410 stainless steel, were investigated. Using a highresolution dilatometer, the samples underwent three cycles of austenitization heat treatment at different temperatures in order to observe the influence of the austenitization temperature with and without tempering on the microstructure, grain size and hardness. The results indicated important influences on the microstructure, grain size and hardness at different austenitization temperatures even with and without tempering. The results also showed that the amount of dissolution of the carbides at the three austenitizing temperatures was directly related to the influences noted discussed earlier. Subsequently, non-isothermal tempering cycles at 677 ° C were performed with different holding times to study the evolution of the microstructure during the tempering heat treatment. The complete cycle considered in this study is the tempering cycle of the industrial partner Finkl Steel where the aim was to gain a better understanding of the evolution of the microstructure during the complete industrial tempering cycle. The results obtained demonstrated a progressive evolution of the various parameters studied until the end of the first tempering. After the first tempering, several industrial requirements were already obtained. As the typical industrial tempering cycle of AISI 410 stainless steel is a double tempering, the results indicated that the evolution of the microstructure on second tempering slows down considerably and that it is possible that a second tempering is not necessary.

Date	29 Mar 2021
Original language	French
Awarding Institution	École de technologie supérieure
Supervisor	Mohammad Jahazi (Co-supervisor) & Henri Champliaud (Co-supervisor)