Microstructure and electrochemical behaviour of laser clad stainless steel 410 substrate with stainless steel 420 particles

Stainless steel (SS) 410 is widely used in many engineering applications such as turbines, nuclear reactor components and seamless pipes due to its superior mechanical properties i.e., high mechanical strength, creep resistance and ductility. Corrosion resistance is an important property which is required for these components to reduce the material degradation from the surface. In the present study, an investigation has been made to enhance the electrochemical behavior of SS410 by depositing SS420 particles using the laser cladding technique. The hardness measured through nano-indentation tests and microstructure of the resulting surface were analysed. Also, electrochemical studies were performed on laser clad specimens with different durations such as 0 h, 8 h, 14 h and 36 h. The improvements in corrosion resistance were analysed using polarization curves and electrochemical impedance spectroscopy (EIS). Further, the morphology and roughness of the corroded surface were analysed. The results showed that a closely packed acicular structure was formed through cladding, which improved the nanohardness compared to the base material. In addition, the clad specimen with 14 h test duration exhibited excellent corrosion resistance amongst the other specimens. The morphological analysis of the corroded specimen revealed the formation of oxides which is indentified to be a major reason for improved corrosion resistance.