Residual stress and cracking behaviors of Cr13Ni5Si2 based composite coatings prepared by laser-induction hybrid cladding

Abstract

Cr13Ni5Si2 based composite coatings were prepared by laser-induction hybrid cladding (LIHC). Residual stresses in the composite coatings were characterized by X-ray based layer-removal method, and dye penetrant testing was adopted to inspect cracks in the coatings. Results indicate that, LIHC not only can remarkably reduce residual stress in the composite coatings, but also can completely avoid cracks in the large area and high thickness hard facing coatings. Furthermore, a residual stress evolution model for the LIHC was established, and it reveals that temperature difference between the composite coating and the substrate is the main inducement that leads to residual stress, and dwell time of the coating in the temperature range of 800°C to 500°C (t8–5) is an important factor that affects residual stress releasing. Due to the hybrid effect of laser beam and induction heating, temperature difference between the coating and the substrate decreased, and t8–5 increased. As a result, residual stresses were decreased remarkably and cracks in the composite coatings were avoided.