| 摘要 |
PURPOSE:To decrease generation of erosion in the upper part on the inside surface of a nozzle and to improve propelling performance of a ship by depositing a Co-base alloy contg. NbC, VC and TiC by build-up welding to the upper part on the inside surface of the nozzle. CONSTITUTION:The nozzle 1 of a nozzle propeller is formed of an austenitic stainless steel, etc. A build-up metal layer 3 consisting of the Co-base alloy contg. >=1 kinds among hard carbides such as NbC, VC and TiC at >=40% by volume is formed over about 1/3 periphery of the upper part of the inside surface of said nozzle 1. Then the upper part of the inside surface of the nozzle 1 withstands severe cavitation so that the generation of erosion is decreased. The nozzle propeller which permits long period sailing is obtd. |
