Estimation of displacement field for turbine blade profile based on reverse engineering in investment casting

An estimation algorithm was proposed to calculate the displacement field of turbine blade profile during solidification based on reverse engineering in investment casting. Firstly, the turbine blade profile was reconstructed based on measured data from coordinate measuring machine (CMM). Secondly, two-step match algorithm was employedto calculate the rotating and translating matrixes which were defined as the best space transformation of reconstructed profile to CAD model profile. Thirdly, the normal offset-distance of every node between the reconstructed profile and CAD model profile was calculated to be suggested as displacement of the node, which can be used for accurate modification of sequent mould. The practical validation shows that the method mentioned can achieve the accurate estimation for displacement of turbine blade profile in investment casting, providing a desirable basis for mould modification.