Residual stress analysis in Inconel-718 milled turbine disk

Residual stress state in turbine disk after machining could affect the life of the disk. For this reason, a strong effort is made today to predict the residual stress distribution by modelling the machining process. However, it should be stressed that the numerical models need of reliable and trusty experimental data to be validated and calibrated. This work is focused on the experimental detection of the residual stress state produced after milling in turbine disk made of Inconel 718, the aim is to supply an experimental database for numerical models validation. The residual stresses were detected by means of X-ray diffraction technique. The robustness of the adopted measurement technique was proved by means of an experimental plan of comparison of measurements among different diffractometers. A database of surface residual stress values and depth profiles was obtained. From these data, the effect of varying cutting parameters (cutting speed, feed rate and tool wear) was evaluated and compared with other results in the literature. Copyright © 2008, Inderscience Publishers.