An adaptive clamp system for deformation control of aerospace thin-walled parts

The assembly and service of thin-walled parts are usually threatened by machining deformation. In this study, phase change material (Sn-Bi-Pb-Cd alloy with a melting point of 70 °C) was used to develop an adaptive clamp system, which could adjust the clamping position when the material was liquid to follow the stress-releasing deformation after rough machining. The material's solidification could re-clamp the workpiece, whose internal stress had been minimized. Afterwards, the workpiece deformation could be removed in finishing machining. Comparing to the counterpart using traditional vacuum fixture, the maximum deformation and the flatness tolerance of the web using the adaptive clamp system reduced by 82.0 % and 72.9 %, respectively, thus effectively improving the accuracy of thin-walled parts manufacturing.