Laser treatment of 430 ferritic stainless steel for enhanced mechanical properties

Thin AISI 430 ferritic stainless steel sheets containing 18% Cr were hardened by continuous-wave laser beams under different conditions. A symmetric double treatment platform was developed to operate two lasers simultaneously in order achieve a homogenous microstructure through the specimen and avoid overheating associated with single treatments on one surface. The influence of linear energy density shielding gas hardness is investigated for both treatments. Tensile behavior oxidation effect during are also studied. With peak temperature around Tm, single-track yields local microhardness that 90% higher than base material, while samples completely treated multi-track present 60% increase yield stress 45.8% ultimate tensile stress. These improvements mechanical behaviors driven formation martensite chromium carbides upon rapid cooling despite poor carbon content dramatic grain coarsening. results could be useful locally modify medium chrome meet industrial requirements.