Thermogravimetric studies of high temperature reactions between potassium salts and chromium

► K2CO3 reacted with Cr2O3 forming K2CrO4. ► Presence of chlorine did not alone explain the initiation of accelerated oxidation. ► More light was shed to the role of chromates in accelerated oxidation. ► Accelerated oxidation of chromia protected steels occurs in two consecutive stages. ► Both potassium and chloride are required, so that both stages of reaction occur.