Thermodynamic Simulation of Low Temperature Colossal Carburization of Austenitic Stainless Steel

Low temperature colossal carburization (LTCC), as a new and more efficient surface strengthening technology, is generally used to enhance the wear and fatigue resistance of austenitic stainless steel, and not harmful to excellent corrosion resistance. In the present paper, a thermodynamic model was developed by means of diffusion-controlled transformations (DICTRA) method, which can investigate carbon concentration distribution and growth regularity of carburized layer on austenitic stainless steel surface treated by LTCC. Meanwhile, an experimental investigation on carburization layer evolution was performed for 316L stainless steel to verify the validity of the model. The results show that the simulated carbon concentration distribution is well consistent with experimental data. With the assistance of the thermodynamic model, the key parameters such as carburizing temperature and time, carbon activity of carburizing gas and alloying element content may be analyzed for optimizing of LTCC.