MECHANICAL & TRIBOCORROSION BEHAVIOUR OF ULTRA-FINE GRAINED 316L STAINLESS STEEL

Abstract

Stainless steels are primarily chosen for their corrosion resistance. Most commonly used grades are the non-magnetic austenitic kind. Using severe plastic deformation processes results in grain refinement which contributes for improved strength and weight saving for many applications. If the combined action of wear and corrosion, commonly known as the tribo-corrosion behaviour, of severely plastic deformation processed steel is comparable to the as-received steel then its use in biomedical implants, chemical processing equipment, and food-processing industries will be justified. Most of the orthopaedic implants fail due to combined action of wear and corrosion in the body fluids. Therefore, the main aim of the current work is to study the microstructural evolution and tribocorrosion behaviour of ultra-fine grained 316L stainless steel, a grade that can be used in body implants and other industrial applications. For microstructural analysis, optical microscopy, scanning electron microscopy and transmission electron microscopy was carried out, which showed extreme grain refinement in MAFed samples. Hardness testing was performed on multi-axially forged samples. Corrosion and tribocorrosion behaviour is evaluated which showed an improvement in uniform corrosion rate and wear resistance of MAFed samples in Hanks’ solution.