Development and characterization of hot dip aluminide coated stainless steel 316L

Stainless steel (SS) grade 316L is used for orthopedic implants due to its biocompatibility; yet the effort should be done to minimize the carcinogenic and inflammatory effects related to SS 316L implants. In this research, aluminide coating of Al–Si alloy on SS 316L is characterized by using optical microscopy, energy dispersive spectroscopy (EDS), nano-indentation and corrosion testing technique. Hot dip aluminizing process is used to coat the SS 316L specimens at 765 °C for 2 min immersion time. Half of the specimens are also diffusion treated in a Muffle furnace at 550 °C for 4 h to produce diffused specimens of SS 316L. Microstructural examination shows the formation of flat coating/substrate interface due to Si addition. EDS analysis confirms the formation of complex intermetallic at the coating/substrate interface which finally results in increasing the hardness and corrosion resistance properties of coating.