Research Projects

Austenitic stainless steels (ASS) are a unique class of sustainable engineering materials based on austenite stabilizing elements. They are divided into two major variants: Cr-Ni based (300 series) and Cr-Mn based (200 series). Due to the high cost of nickel, conventional Cr-Ni based ASS is expensive. A new alternative, Cr-Mn based ASS, has been developed, which stabilizes austenite through manganese and nitrogen addition. Copper addition in ASS has been found to improve its stability and formability, and is known for its anti-microbial properties. Cu-addition in ASS is considered a potential method to obtain anti-microbial structural materials with sufficient corrosion resistance. The design of the chemistry and processing routes can engineer the presence of copper to achieve optimally balanced mechanical, corrosion, and antimicrobial properties in the steel. This Cr-Mn based ASS also needs good fabricability in terms of formability and weldability. Understanding the effect of copper addition on formability in low-Ni, Cr-Mn based ASS is essential for various structural applications. Friction stir welding is an efficient joining or crack repairing method to overcome drawbacks of fusion welding, such as austenite instability due to manganese loss in the fusion zone and high residual stress. The current proposal aims to study various processing routes to achieve a microstructure capable of providing satisfactory mechanical, corrosion, and antimicrobial properties in Cu-bearing Cr-Mn based ASS with low-Ni addition.