| 摘要 |
The surface of a relatively short metal tube is partly or completely coated with a metal by a conventional process and then subjected to flow forming to increase its length. The tube is pref. steel and the coating metal is Al, Ni, Cd or Ti, applied either by vapour deposition in high vacuum or electroplating to give a thickness ratio tube wall: coating between 1:0.01 and 1:0.1. After flow forming, the coating metal is pref. oxidised and sealed. A thin, intermediate coating may be applied between the tube and the coating. Used for drums for gas centrifuges, or combustion chambers for rockets. Improves the corrosion resistance of the finished tube, esp. in the bore. |
