(1. 哈爾濱工業(yè)大學(xué) 化工學(xué)院，哈爾濱 150001；
2. 杭州東方表面技術(shù)有限公司，杭州 311122)
摘 要: 為解決電鍍鉻工藝嚴(yán)重污染環(huán)境的問題，制備低污染且具有良好外觀的Ni-Co-B合金代硬鉻鍍層。采用單因素實驗分別討論電鍍液組成及工藝條件對鍍層硬度、外觀、沉積速度及陰極電流效率等的影響，確定較優(yōu)的鍍液組成及工藝條件，考察優(yōu)化條件下所得鍍層經(jīng)不同溫度熱處理后的鍍層硬度，分析鍍液的極化情況和200 ℃熱處理1 h前后鍍層的表面形貌、晶體結(jié)構(gòu)及耐蝕性。結(jié)果表明：優(yōu)化條件下得到的合金鍍層為納米晶結(jié)構(gòu)，宏觀上均勻光亮，微觀上平整、無孔隙，經(jīng)200 ℃熱處理1 h后晶體顆粒進行重結(jié)晶，晶粒尺寸略有增大，鍍層表面更加致密，硬度達10.875 GPa，高于硬鉻鍍層的，且耐蝕性與硬鉻鍍層的相當(dāng)。該電鍍工藝有望取代電鍍硬鉻工藝而獲得廣泛應(yīng)用。
關(guān)鍵字: Ni-Co-B合金；納米晶；電鍍；代鉻鍍層；顯微硬度
（1. School of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin 150001, China;
2. Hangzhou Oriental Metal Finishing Technology Co., Ltd., Hangzhou 311122, China）
Abstract:To solve the problem of serious environmental pollution from electroplating chromium process, electroplating Ni-Co-B alloy coatings, which are environment-friendly and with good appearance, were prepared to substitute the hard chromium coating. The effects of electrolyte solution composition and process conditions on the microhardness, appearance, deposition rate of the coatings and current efficiency of the cathode were discussed by single factor experiments. Relatively better compositions of the electrolyte and process conditions were gained. The effects of different heat treatment temperatures on the microhardness of the coatings prepared under the optimized condition were measured. The polarization of electrolyte was analyzed. The surface morphology, microstructure and corrosion resistance of the coatings before and after heat treatment at 200 ℃ for 1 h were characterized. The results show that alloy coatings prepared under the optimized condition are nanocrystalline structure, bright and uniform in macrography, smooth and seamless in micrography. After heat treatment, the grain sizes of coatings slightly increase because of recrystallization, the surfaces b, ecome more compact, and the microhardness can be up to 10.875 GPa, which is higher than that of hard chromium coating. Also, the corrosion resistance of alloy coatings after heat treatment is roughly equivalent to that of hard chromium coating. So, this electroplating process is expected to replace the hard chromium plating technology and be widely applied.
Key words: Ni-Co-B alloy; nanocrystalline; electroplating; substituting chromium coating; microhardness
