High Temperature Oxidation Resistance of High Contained Silicon Alloys: Austenitic Steel 153MA

Abstract

153-MA develops a protective oxide film under an oxygen atmosphere at high temperature. The experiments were performed at two different temperatures in air, at atmospheric pressure, up to 15 cycles each, consisting of a 10 hours period (1073.15 K and 1173.15 K) heating and 30 minute cooling at room temperature. The kinetic behavior of 153MA was modeled using 3 samples per temperature, each showing increasing mass variation as product of the oxide formation. The techniques used to characterize the structure and composition of the oxidation products formed; XRD, SEM and EDS. This velocity difference depends on diffusion properties, also the protective coat show swelling and anchored on the base metal. The main component of this coating is Cr₂O₃, spinel (Mn,Cr)₃O₄, mixing oxides Fe,Cr and SiO₂. At higher temperatures the coating adherence is lost and becomes porous. Regenerative capacity of the oxides becomes less effective with the increment of cycles.