Mechanical Response and Failure Evolution of 304L Stainless Steel under the Combined Action of Mechanical Loading and Laser Heating

Abstract

Deformation and fracture properties of structural materials are greatly influenced by the factors like applied load, state of stress, and temperature. A precise prediction of the material properties of stainless steel at elevated temperature is necessary for determining the load-carrying capacity of structures under severe conditions. The present work reports the deformation and failure characteristics of 304L stainless steel subjected to combined laser heating and mechanical loading. The effect of main parameters on stress-strain, fracture characteristics, failure time, and temperature profile of specimens have been explored. Specimens were subjected to prescribed loading states, and then irradiated by a continuous wave fiber (1.08 µm) laser. The stress-strain curves indicated that the specimens experienced slight strain hardening in a specific temperature range prior to fracture. The specimen's ultimate failure time is found to be reduced by increasing either laser power density or preload level. Fracture on a microscopic scale was predominantly ductile, comprising dimples as well as micro-void nucleation, growth, and coalescence. With the increase of laser power density, dimples rupture is the primary fracture mode, while with the increase of preload value, relatively more in-depth and severe deformation effects were observed. The description and characterization of 304L stainless steel failure under the simultaneous action of laser heating and tensile stress have been explored in detail.

Simulated Heat Affected Zone in Welded Stainless Steel 304l

“…The microstructure and the hardness change from the base metal to the fusion zone, i.e., the microstructure of the nearest subzone to the FZ has the lowest hardness and the highest grains size; however the nearest subzone to the BM has the highest hardness and the lowest grains size. Jelani et al [19] concluded that the sensitivity of the mechanical properties of 304L stainless steel to temperature, i.e., the material becomes softer and more ductile with the increase of the temperature up to 900 °C. For this reason, the nearest subzone to the FZ has the lowest hardness.…”

Microstructure and Mechanical Properties of (Ti, Nb)C Ceramic-Reinforced 316L Stainless Steel Coating by Laser Cladding

“…However, as austenitic stainless steel, the low hardness and poor wear resistance of 316L stainless steel limit its wider application [4][5][6][7]. Surface strengthening techniques such as carburizing, nitriding, local heat treatment, and shot peening have been employed in practical applications to improve the surface properties of 316L steel [8,9]. Zhou et al [10] investigated the effect of shot peening intensity on the surface integrity and fatigue life of 316L stainless steel.…”