Residual stress determination of ductile cast iron by means of neutron diffraction

Abstract

A study was undertaken to simulate the casting process, using simulation software, of a ductile iron casting (for use as a valve body) and in doing so, to determine the order of residual stress and experimentally verify the simulation results. The simulation was carried out using MAGMASOFT® simulation software, where after the residual stress results were extracted. The residual stress results were verified using neutron diffraction strain measurements. The simulation and verification were also done on samples subjected to heat treatment and machining in order to determine the effects it had on residual stress within the components. The measured residual stress results were found not to compare very well with the simulation predictions of MAGMASOFT®. Numerous reasons were provided for this in the report. The residual stress results, by means of neutron diffraction versus the residual stress results obtained by the MAGMASOFT® simulation for the heat treated and machined samples, also did not compare very well. However, the results of both neutron diffraction and MAGMASOFT®, showed a decrease in residual stress.