| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To suppress corrosion of both a shaft and a hard material sleeve used in water (fresh water, river water), in chemicals (various chemicals), polluted water, and sea water. <P>SOLUTION: Regarding a natural electrode potential in a solution in the environment in use of the metallic shaft and the hard material sleeve of a pump, the hard material sleeve side forms a noble member, and the metallic shaft side forms a base material, and the difference of the natural electrode potential between the both is set 200mV or less. The progress of corrosion therefor is slowed, making it possible to obtain a shaft for a pump with a long service life. <P>COPYRIGHT: (C)2004,JPO</p> |
