(V) Understanding stress corrosion cracking of TRIP Fe39Mn20Co20Cr15Si5Al1 (at.%) high entropy alloy using slow strain rate testing

Stress corrosion cracking (SCC) includes combined action of stress and corrosive environment on a susceptible material that might lead to catastrophic failure of an engineering component. So, there is a need for advanced materials with better SCC resistance in a wide range of applications. A new class of metallic materials, widely known as high entropy alloys (HEAs), has shown promising properties. However, the SCC behavior of HEAs has not been explored yet. The present study examines the SCC behavior of a transformation-induced-plasticity (TRIP) Fe₃₉Mn₂₀Co₂₀Cr₁₅Si₅Al₁ (at.%) HEA in 3.5 wt.% NaCl solution at room temperature. The SCC evaluation was carried out by performing slow strain rate testing (SSRT) of smooth dog-bone shaped tensile specimens at strain rates of 10^-6, 10^-5 and 10^-4 s^-1. The microstructural characterization before and after SCC tests has been conducted using advanced characterization tools including X-ray photoelectron spectroscopy and transmission electron microscopy. The preliminary results of SSRT show a decrease in ductility and ultimate tensile strength with a decrease in strain-rate and no dependence of yield strength on strain rate. Further analysis of SSRT data obtained at different strain rates and post-deformation microstructure including identification of corrosion product(s) and passivation film is in progress and will be discussed during presentation.