Failure in 3D-printed composite parts is complex due to anisotropic properties, which are mainly governed by printing parameters, printing strategy, and materials. Understanding the failure behaviour of materials is crucial for the design calculations of parts. Effective computational methodologies are yet not available for accurately capturing the failure behaviour of 3D-printed parts. Therefore, we proposed two different computational methodologies for modelling the failure behaviour of 3D-printed parts. 3D-printed parts subjected to uniaxial tensile loading were considered for modelling. In the first method, the computational model employed nonlinear properties of virgin material, and the model predicted higher values than the experimental results. This method provided idealistic nonlinear behaviour of 3D-printed parts. The difference in the results of experimental and computational is significant, especially in the case of 3D-printed composites. In the second method, the computational model utilized nonlinear material data from mechanical testing results and the model predicted accurate nonlinear behaviour of 3D-printed parts. This method provided realistic material behaviour of 3D-printed parts. Therefore, for effective design and analysis, it is suggested to use the latter computational methodology to capture the failure behaviour of 3D-printed parts accurately.

The 25Cr7Ni stainless steel alloy system is gaining increasing interest in the oil and gas industry because of its combination of high strength and corrosion resistance properties. However, very few studies on the effects of starting powder attributes and chemical composition on the as-printed properties of 25Cr7Ni stainless steel fabricated through laser-powder bed fusion (L-PBF) exist in the literature. This study examined the influence of powder attributes and chemical composition on the samples from gas atomized and water atomized 25Cr7Ni stainless steel powders, fabricated through L-PBF, on their as-printed microstructure and properties. The mechanical properties that were examined included ultimate tensile strength (UTS), elongation (%), and hardness. The corrosion behavior was also studied using linear sweep voltammetry in 3.5 wt.% NaCl solution. The evolved phases were characterized using optical and scanning electron microscopy, as well as through X-ray diffraction. The gas atomized powders, with their spherical and uniform morphology, yielded as-printed parts of higher relative densities when compared to water atomized powders, with irregular morphology due to better powder bed compaction. The higher densification obtained in the L-PBF samples from gas atomized powders translated into the highest UTS, hardness, and yield strength among the L-PBF samples from water atomized powders and wrought–annealed 25Cr7Ni stainless steel. The presence of higher amounts of N and Mn in the chemical composition of the gas atomized powders over water atomized powders promoted the presence of retained austenite in the corresponding L-PBF samples. Higher amounts of Mo, combined with austenite content, yielded a higher corrosion resistance in the L-PBF samples from the gas atomized powder than in the L-PBF samples from the water atomized powders. The latter part of the work is focused on the evaluation of simulation parameters for analyzing the fabrication procedure for the L-PBF process using Simufact software. For a given set of process parameters, Simufact provides the distortion and internal stresses developed in the printed parts as output. The present study sought to evaluate the process simulation by comparing the experimental observations in terms of the part distortion achieved in a stainless steel cube fabricated through L-PBF with Simufact process simulation obtained using the same set of process parameters.