A kind of manganese-magnesium phosphating solution

Abstract

The invention discloses a manganese &magnesium-based phosphating solution and relates to the technical field of standard component surface treatment. The manganese &magnesium-based phosphating solution adopts water as the solvent and further comprises the following components including, by mass concentration, 200-300 g / l of manganous dihydrogen phosphate, 50-90 g / l of manganese nitrate, 70-120 g / l of magnesium nitrate, 40-50 g / l of nitric acid, 2-4 g / l of nitrilotriacetic acid and 3-5g / l of hexafluorozirconic acid. According to the manganese & magnesium-based phosphating solution, by adding the specific contents of magnesium nitrate, nitrilotriacetic acid and hexafluorozirconic acid into the phosphating solution, the compaction degree of phosphating film produced after phosphating treatment is performed is greatly increased, the produced phosphating film is continuous and compact with no crystal can be seen, accordingly, the phosphating film is made to have the excellent corrosion resistance and abrasion resistance, meanwhile, the thickness of the phosphating film can reach up to 18 mum or above, the number of abrasion resistance times can reach up to 11 or above, in addition, thestability of the manganese & magnesium-based phosphating solution provided by the invention is good, the amount of phosphorus slag produced after phosphating treatment is performed is quite small, the phosphorus slag starts being produced after 9-12 times of phosphating is performed, environment friendliness is achieved, and the phosphating solution is quite suitable for being applied to phosphating treatment on steel standard components.

Description

technical field [0001] The invention relates to the technical field of surface treatment of standard parts, in particular to a manganese-magnesium phosphating solution. Background technique [0002] At present, zinc-manganese series medium-temperature phosphating solution is usually used to treat the surface of steel standard parts. The thickness and adhesion of the manganese-iron film or zinc-manganese-iron film formed after surface treatment are acceptable. In addition, the phosphating film produced also has certain corrosion resistance. However, due to the large particle size of manganese ions or zinc ions, the crystalline particles of manganese hydrogen phosphate and zinc hydrogen phosphate, the main components of the film, are relatively coarse, so the phosphating film is relatively loose and the compactness of the film is poor, so there are gaps between the phosphating films. Acidic phosphating solution may be brought into the gaps. Although passivation treatment can ...

AI Technical Summary

Problems solved by technology

However, due to the large particle size of manganese ions or zinc ions, the crystalline particles of manganese hydrogen phosphate and zinc hydrogen phosphate, the main components of the film, are relatively coarse, so the phosphating film is relatively loose and the compactness of the film is poor, so there are gaps between the phosphating films. Acidic phosphating solution may be brought into the gaps. Although passivation treatment can be carried out after phosphating, the passivation solution is alkaline. Although it can neutralize the acidic phosphating solution brought in to a certain extent, the phosphating film The gaps between the gaps still exist, and air and moisture will fill the gaps, which will greatly reduce the corrosion resistance and wear resistance of the film. The corrosion resistance and wear resistance of the existing zinc-manganese phosphating solution can no longer meet the increasingly high market requirements.

[0003] In addition, the use of zinc-manganese phosphating solution for surface treatment is likely to produce a large amount of phosphorus slag, which has caused serious pollution to the environment.

Images