TY - JOUR ID - 71259 TI - Pretreatment of Gray Cast Iron for Hard Chromium Electroplating (RESEARCH NOTES) JO - International Journal of Engineering JA - IJE LA - en SN - 1025-2495 AU - Afshar, A. AD - Materials Engineering, Sharif University of Technology Y1 - 2000 PY - 2000 VL - 13 IS - 2 SP - 81 EP - 84 KW - Gray Cast Iron KW - Chromium Plating KW - Electroplating KW - Hard Chromium DO - N2 - From the standpoint of processing, hard chromium layer plate may be applied to steels, cast iron, aluminum and nickel base alloys. Cast iron can be plated provided that the surface is capable of conducting the required current and is reasonably free of voids, pits, gross silicate inclusions, and massive segregation. There are many difficulties arising from graphite phase and deposition of hydrogen on the surface of gray cast iron (G.C.J). To obtain desired hard chromium coating with acceptable adhesion, special pretreatments should be used. In this paper the surfaces of G.C.I. were prepared in sulphuric acid, chromic acid + S04--  by anodic etching phosphoric acid + sulphuric acid solution by electro polishing and sulphuric acid + fluoridric solution by dipping in the different conditions. The best results for removal of graphite from the surface of specimens are obtained after anodic etching in 60%  H2S04 solution. UR - https://www.ije.ir/article_71259.html L1 - https://www.ije.ir/article_71259_34cf5897d6ea5cf6b2d7080f6c6517c7.pdf ER -