In situ X-ray phase analysis and computer simulation of carbide dissolution of ball bearing steel at different austenitizing temperatures

This paper presents the results of in situ X-ray diffraction experiments and computer simulation of AISI 52100 steel during soaking at different austenitizing temperatures. A study of carbide dissolution kinetics and austenite lattice parameter variations has been executed. In situ X-ray diffraction investigations were carried out with a rotating anode and an area detector to allow a good time resolution. For the computer simulation, a Johnson–Mehl–Avrami equation was used. Lattice parameters of austenite obtained by X-ray diffraction show good agreement with values calculated from a model based on neutron diffraction experiments. Carbide contents measured by X-ray diffraction are close to those obtained by simulation. But discrepancies are present which are essentially due to local heterogeneity of the chemical composition.