Evaluating the effect of repair using direct laser metal deposition on the fracture resistance of the cracked 1.2714 tool steel component

In this research, the use of direct laser metal deposition repair has been investigated with the aim of using this technique to repair forging mold. Tensile fracture testing was performed according to ASTM E1820 guidelines on single-edge-cracked specimens that were repaired by the DLMD process. In this study, the effect of laser cladding process parameters (laser power and percentage of reinforcing nanoparticles) as well as the effect of crack length on the remaining strength were investigated. In the following, the experimental displacement field obtained from the analysis of digital image correlation was used to create boundary conditions for a finite element post-processing model. The finite element model was calculated using a developed code and the fields of stress and strain as well as the J-integral parameter for coated and without coating samples. The results show that by increasing the laser power from 150 to 450 W and by increasing the percentage of nanoparticles of SiC from 0 to 5%, the failure load of the samples increases by 171 and 139%, respectively, and the J-integral parameter is reduced by 32 and 41%, respectively. On the other hand, it was observed that by reducing the crack length from 25 to 3 mm, the failure load of the samples increased by 158 and 240%, respectively, and the J-integral parameter also decreased by 55 and 40%, respectively.