PROPERTIES OF CONVERSION COATINGS FOR ZINC FILM ON SODA-LIME SILICATE SURFACE

• Main Authors: Tsung-Han Lu, 呂宗翰
• Other Authors: Chao-Hwa Liu
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/07904300536608793522

碩士 === 淡江大學 === 機械與機電工程學系碩士班 === 100 === The conversion coatings of zinc film on the soda-lime silicate surface comparing with bulk zinc in CuSO4/NaCl aqueous solution were investigated. For bulk zinc, first, the black coatings (Zn, Cu and Cu (OH) 2) formed on the surface. Next, copper was precipitated between the black coatings and bulk zinc. Then, part of black coatings fell off and formed the yellow powder (Cu2O). After that, yellow powder turned into green powder (CuCl2 complexes). At last, the surface of bulk zinc was covered by zinc oxide. For zinc film, the change of color was as follows: black coatings (Zn, Cu and Cu (OH) 2), red coatings (Cu), yellow coatings (Cu2O) and green coatings (CuCl2). The activation energy of zinc film for the conversion coatings in 0.6wt%, 1.2wt% and 2.3wt% CuSO4/NaCl aqueous solution are 33.60(J/mol), 28.21(J/mol) and 14.87(J/mol), respectively.