The Oxidation Kinetic and Oxidation Mass Transfer of 10CrNi3MoV Steel at High Temperature

Abstract

The isothermal and non-isothermal oxidation kinetic of 10CrNi3MoV steel from 900°C to 1200°C were studied in this paper, which aimed to clarify the oxidation characteristics of the steel in high-temperature service environments and to provide theoretical support for its engineering applications. The weight loss per area increased with the increasing temperature, which intuitively reflects the enhancement of the oxidation intensity of the steel at high temperatures. The value of activation energy (Ea) was 124.82 KJ/mol for the 10CrNi3MoV steel through the determination of non-isothermal oxidation kinetic. The isothermal oxidation kinetic had been studied from 900°C to 1200°C for 720 min. This indicated that the oxidation rate reaction constant (K_p) showed a gradual increasing trend with the increase of oxidation temperature, following the function relationship given by \(k_{p} = 7.24 \times 10^{4} {\text{exp}}\left( { - 15.10 \times 10^{3} /T} \right)\). In addition, the thickness of the oxide film formed by outward transfer diffusion was larger than that by inward transfer diffusion, which indicated outward transfer diffusion of iron ions mainly controlled the oxidation mass transfer during the high-temperature oxidation reaction. The composition's microscopic phases formed during the high-temperature treatment were examined by scanning electron microscopy with energy-dispersive spectrometry (SEM-EDS). This indicated the chromium, silicon, and nickel element-enriched layers formed at the interface between the steel substrate and the oxide scale during the high-temperature treatment. The Fe-Ni phase and Ferrite phase intersected with each other at the interface. The steel had internal oxidation during the high-temperature treatment.