Influence of post-heat treatments on fatigue response of low-alloyed carbon-manganese steel material manufactured by Direct Energy Deposition-Arc technique

摘要

The main idea of this paper is improving fatigue response of a low-alloyed carbon-manganese steel material manufactured by Direct Energy Deposition-Arc technique using post-heat treatments. Four series of fatigue specimens are machined from a 3D printed wall. The machined samples are austenitized following a direct quenching and tempering processes at two different temperatures. All samples are subjected to rotating bending fatigue loading conditions. Next, microhardness, microstructures and fracture surfaces of the fatigue samples are analysed. Despite of very low carbon content, a full martensitic transformation was observed after the post-heat treatments which resulted in considerably higher fatigue lifetimes compared to non-treated ones. The quenched samples gave the best improvement when compared to as-printed and tempered samples.