Electroplating liquid of trivalent chromium system for ferrochrome electrodeposition and preparation method thereof

Abstract

The invention discloses electroplating liquid of a trivalent chromium system for ferrochrome electrodeposition and a preparation method thereof. A solvent of the electroplating liquid is water, and pHis 2.7-4.5. Solutes comprise trivalent chromium main salt, a trivalent chromium main complexing agent, a trivalent chromium auxiliary complexing agent, ferrous main salt, conducting salt, a buffer agent, a stabilizer, a surface active agent and a composite brightening agent. Trivalent chromium is coordinated in a composite coordinating mode, the coordinating capacity of water molecules on the trivalent chromium is lowered, and thus the deposition efficiency of chromium on the surface of a cathode is improved. The specific main complexing agent is micromolecular carboxylic acid and salt of themicromolecular carboxylic acid and can replace the water molecules to be complexed with the trivalent chromium, trivalent chromium electroreduction is promoted, the main complexing agent and the specific auxiliary complexing agent are complexed with trivalent chromium ions jointly to form a combined composite complex, and trivalent chromium electroreduction is further promoted.

Description

Technical field [0001] The invention belongs to the technical field of electroplating solutions, and in particular relates to a trivalent chromium system electroplating solution for electrodepositing ferrochrome alloys and a preparation method thereof. Background technique [0002] Ferrochrome alloys have high mechanical strength and hardness. Among them, amorphous ferrochrome alloys also have excellent magnetic properties, excellent corrosion resistance and electrocatalytic activity. [0003] The preparation methods of ferrochromium alloy are mainly electric furnace method, shaft furnace method, plasma method, smelting reduction method and electrodeposition method. Among them, the preparation of ferrochrome alloys by electrodeposition has the advantages of simple operation, low cost, controllable alloy composition and thickness, and electroplating on the surface of complex parts. [0004] Ma Zhengqing et al. (Ma Zhengqing, Li Wenxian, Tan Dunqiang, Xiao Yude, Yu Kun. Research on el...

AI Technical Summary

Problems solved by technology

[0005] At present, the electroplating process for preparing ferrochrome alloys mostly uses a single complexing agent, which easily leads to a large difference in the deposition potential of trivalent chromium and ferrous iron complexes in the plating solution, which is not conducive to the co-deposition of ferrochrome alloys; most of the plating solutions lack suitable Stabilizer, Fe 2+ easily oxidized to Fe 3+ , affecting the stability of the plating solution; the structure and iron content of the ferrochrome alloy coating are single, lacking the controllability of the proportion of ferrochromium in the coating and the crystal structure of the coating

Images