Measurement of the phase transformation in sheet steel from the ferrite to austenite phase using angular dispersive X-ray diffraction in a transmission geometry

An angular dispersive X-ray diffraction arrangement, utilising an image intensifier and X-ray filtering, has been developed to measure the ferrite to austenite phase transformation in an online steel foundry process line. Given the degradation in resolution associated with transmission measurements, the extreme phases have been used to calibrate the system. The most significant differences between these two phases are found to occur at scattering angles of between 6° and 8°. The results obtained from measurement of the radially integrated profile in this region whilst heating a ferrite-phase sample towards the phase transformation temperature are consistent with the expected trend, demonstrating the requirement for uniform temperature between the ferrite and austenite phase samples in order to observe the phase transformation.