Study on Microstructure and Anti-Corrosion Property of Stainless Steel Particles Deposition on Ti–6Al–4 V Substrate using Laser Cladding Technique

In the present study, the Stainless Steel (SS420) particles is deposited on Ti–6Al–4 V (Ti-64) substrate using laser cladding process. The cladded structure and hardness were analysed through Field Emission Scanning Electron Microscopy (FESEM) and Nanoindenters, respectively. Then, the corrosion behaviour of the cladded surface was analysed with polarization test and electrochemical impedance method with different testing hours (0, 18 and 42 h). Further, the roughness of the corroded surface was measured using laser confocal microscopy. Result showed that the laser cladded surface shows with three structures namely, coaxial dendrites, columnar dendrites and cellular dendrites. The cladding nanohardness (10.58 GPa) was higher while compared with base (4.53 GPa) and interface regions (5.89 GPa). Corrosion current density at 18 h test specimen is lower than that at 0 h and 42 h test specimen and improved the corrosion resistance by forming the passive layer at 18 h test specimen. Moreover, lesser roughness was noticed at 18 h test specimen due to reduced corrosion rate.