Evaluation of Residual Stress of HSS Rolls by Ultrasonic and X-ray diffraction based techniques

In this project, first time in-situ residual stress measurement was carried out on rolls at Tata Steel, India. Under this exercise, optimisation of grinding process during profiling of new rolls and in-service mill-out rolls has been established. Attempt has also been made to apply ultrasonic technique using 0.5 MHz surface wave probes to assess the stress condition of the HSS rolls and calibrate the ultrasonic velocity changes with stress as measured by XRD. Calibrated ultrasonic velocity has been used to assess the stress state on one pair of test roll till the full campaign length.