| 摘要 |
<p>Workpiece is heated and then mounted on a mandrel and cooled, after which the mandrel is removed to leave a precise geometric shape of the interior of the workpiece. Specifically the outside may be precision-machined without removal of the mandrel. The mandrel may be of material of linear coefficient of expansion lower than that of the workpiece, and have an initial outside perimeter of its transverse cross-section higher than the initial inside perimeter of the workpiece by the difference in linear expansion of these perimeters during heating.</p> |
