Copper piece surface passivating treatment fluid

Abstract

The invention relates to a copper piece surface passivating treatment fluid. The passivating treatment fluid is composed of 3-7 g/L of benzotriazole, 180-220 mg/L of sodium phosphate, 6-12 g/L of citric acid, 60-90 mg/L of colloidal silicon dioxide and 5-7 ml/L of a wetting agent; and the wetting agent is formed by mixing polyethylene glycol and polyving akohol, and the mass ratio of polyethylene glycol to the polyving akohol is (1.7-2.3):1. The copper piece surface passivating treatment fluid has the beneficial effects that through the synergistic effect of all components, the hydrothermal resisting property of the passivating treatment fluid is greatly improved; in addition, during passivating treatment, chromium ions are not contained, and the environmental protection performance is greatly strengthened; and meanwhile, expensive raw materials are not contained, and the cost of the passivating treatment fluid is greatly reduced.

Description

technical field [0001] The invention belongs to the technical field of metal corrosion and protection, in particular to a copper surface [0002] Passivation treatment solution. Background technique [0003] The processing volume of copper and copper alloy in China is about 10 million tons per year, and its annual output value is more than 600 billion yuan. Generally, after machining copper and copper alloy workpieces, passivation treatment is required to improve their discoloration and corrosion resistance. At present, the passivation of copper and copper alloy products is mainly cleaned by chromic acid and other treatment solutions or their mixtures, but the wastewater after cleaning and passivation treatment using these treatment solutions contains hexavalent chromium ions, which seriously pollutes the environment and affects the safety of operators. In good health. [0004] In response to the above phenomenon, people have improved the passivation treatment solution. F...

AI Technical Summary

Problems solved by technology

At present, the passivation of copper and copper alloy products is mainly cleaned by chromic acid and other treatment solutions or their mixtures, but the wastewater after cleaning and passivation treatment using these treatment solutions contains hexavalent chromium ions, which seriously pollutes the environment and affects the safety of operators. Healthy body

[0004] In response to the above phenomenon, people have improved the passivation treatment solution. For example, the invention patent with application number CN86103910.6 uses benzotriazole and polyvinyl alcohol as passivation agents, but this patent still uses a small amount of chromic acid; The invention patent with application number CN200810187682.6 uses benzotriazole 5-8g / l, 1-phenyl-5 mercaptotetrazolium 2-4g / l, tartaric acid (or citric acid) 14-18g / l, molybdenum The mixed solution of sodium tungstate (or sodium tungstate) 2-4g / l and sodium lauryl sulfate 0.5-1g / l can passivate brass, but the composition of the passivation solution is complex and expensive sodium molybdate or sodium tungstate; the invention patent with application number CN201010595972 .1 uses a mixture of phytic acid, hydrogen peroxide, boric acid, polyethylene glycol, etc. to passivate brass, but this method is also very complicated in composition and plant The phosphorus content in the acid (phytic acid) is very high, which will lead to an increase in the chemical oxygen demand (COD) in the wastewater; and there is a common problem in the above patents: the passivation treatment solution has poor heat and humidity resistance