| 摘要 |
<p>PURPOSE: To prevent sulfuric acid dew point corrosion from corroding a heat transfer pipe surface and thinning the pipe wall, by applying the electroplating of porous Ni, including Mo fine particles, having specific thickness on the surface of a carbon steel pipe, and then giving diffusion-coating to metal Cr containing Al2 O3 powder to form the coat of anticorrosive Ni-Cr-Mo alloy. CONSTITUTION: In the coat of Ni-Cr-Mo alloy obtained by applying the electroplating of porous Ni, containing the Mo fine particles of 1-3μm, to a mainly carbon steel surface, and then diffusion-cementation-treating metal Cr, containing Al2 O3 powder, at 900-1100 deg.C degree; anticorrosion to sulfuric acid is kept by Ni, Cr, and Mo. Also, anticorrosion to sulfuric acid is excellent because of realizing the densification of a coat by the effect of diffusion-cementation- treating. Consequently, when an alloy coat, by porous electroplating + diffusion cementation treating excellent in sulfuric acid corrosion resistance, is formed on a heat transfer pipe surface; the alloy coat protect a heat-transfer pipe to improve the sulfuric acid corrosion resistance of the heat transfer pipe, thereby obtaining an anticorrosion heat-transfer pipe.</p> |
