Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method for preparing chromium based composite coating in environment protection type trivalent chromium plating bath

A composite coating and trivalent chromium technology, applied in the field of electrodeposition, can solve the problems of narrow operating conditions, high cost, and inability to plate thickly, and achieve the effect of wide operating conditions, high bonding strength, and smooth surface

Inactive Publication Date: 2009-07-01
LANZHOU INST OF CHEM PHYSICS CHINESE ACAD OF SCI
View PDF0 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Vapor deposition technology has the advantages of low pollution and uniform deposition, but its cost is high and it cannot be used in large-scale industrial production; electrodeposited alloy chromium plating mainly includes Zn-Sn-Co, Ni-P, Ni-W and other ternary alloy
This method has little pollution, but the stability of the plating solution is poor and the operating conditions are narrow
In contrast, the toxicity of the trivalent chromium electrodeposition solution is only 1% of that of the hexavalent chromium solution, and it consumes less energy and has high efficiency, but its fatal disadvantage is that it cannot be plated thick and has low hardness, so it can only be used for decorative purposes. coatings and cannot be used as wear-resistant coatings and repair coatings

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0019] The electrodeposition method of the present invention is used for plating on the surface of a metal such as steel or copper workpiece, and the pre-plating pretreatment of the workpiece adopts a conventional pre-plating pretreatment process. The formula of trivalent chromium electrodeposition chromium-based composite coating solution is as follows: each liter of electrolyte contains 100-210g of chromium chloride hexahydrate, 40-50g of ammonium bromide, 20-35g of sodium chloride, 20-30g of boric acid, formic acid (or acetic acid, oxalic acid, aminoacetic acid, formates, acetates, oxalates) 0.3-1.0mol, granules 10-100g. The particles are alumina, silicon carbide, zirconia, diamond, silica, graphite, polytetrafluoroethylene or molybdenum disulfide. During electroplating, high-purity graphite is used as anode or titanium plate, and steel or copper workpieces that have undergone conventional pre-plating pretreatment are used as cathodes; the pH value of the electrolyte is con...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
surface roughnessaaaaaaaaaa
thicknessaaaaaaaaaa
thicknessaaaaaaaaaa
Login to View More

Abstract

The invention discloses a method for preparing a chromium-based composite plating layer in an environment-friendly trivalent chromium plating bath. The method adds different particles in a basic electrolyte containing chromium chloride to prepare the chromium-based composite plating layer which has even surface and is firmly combined with a substrate by selecting appropriate process conditions. The method has the advantage that the thickness of the prepared chromium-based composite plating layer is more than 50mu m. The composite plating layer has the hardness higher than that of a hexavalent chrome electroplating layer and the tribological property equivalent to that of the hexavalent chrome electroplating layer, and can substitute the prior hexavalent chrome electroplating technology under various friction working conditions.

Description

technical field [0001] The invention relates to an electrodeposition method for preparing a chromium-based composite coating in an environment-friendly trivalent chromium plating solution. Background technique [0002] Hard chromium coating has become the most widely used electroplating coating in the industry due to its high hardness, good wear resistance and corrosion resistance. But for a long time, the traditional hexavalent chromium plating solution has many insurmountable shortcomings, such as low current efficiency, high plating temperature, serious pollution and so on. In the process of electroplating hard chromium, a large amount of hexavalent chromium in waste water and waste gas will cause great pollution to the environment. Hexavalent chromium can cause human kidney failure, heart failure, leukemia, and can strongly cause cancer. At present, the World Health Organization and countries around the world are paying more and more attention to the pollution of hexava...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C25D3/06C25D15/00
Inventor 张俊彦曾志翔梁爱民
Owner LANZHOU INST OF CHEM PHYSICS CHINESE ACAD OF SCI
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com