SENSITIVITY ANALYSIS OF THE EFFECT OF INTERFACIAL HEAT TRANSFER COEFFICIENT ON DISTORTION SIMULATION DURING QUENCHING

The distortions of C-ring and cut cylinder of austenitic stainless steel after water quenching were investigated using simulation and experiment methods. The results indicated that the accurate measurement of temperature had a major influence on interfacial heat transfer coefficient (IHTC) which is calculated using the inverse analysis method. The sparse data of the high temperature stage due to low sampling frequency resulted in the lower value of IHTC. The simulated distortion during water quenching was mostly decided by the change of IHTC. The simulation results showed that the trend and magnitude of distortion predicted by the IHTCH (calculated from the data of high sampling frequency) agreed better with the experiments than that by the IHTCL (calculated from the data of low sampling frequency). The further analysis showed that the IHTC at high temperature had the great influence on the calculated yield behavior of materials. The high values of IHTC caused that the work piece kept in the yield status at higher temperature and wider temperature range. So the simulation using the IHTCH predicted more serious plastic deformation and larger rigid movement. Further analysis showed that the simulation result of distortions was sensitive to the variation of IHTC at the high temperature stage, while insensitive to the variation at the low temperature stage.