Process for producing green passivation coating of cadmium-plated workpiece

A production process and passivation film technology, applied in the direction of metal material coating process, etc., can solve problems such as easy to be scratched, large color difference, poor wear resistance, etc., and achieve strong salt spray corrosion resistance and color change The effect of small size and improved wear resistance

Active Publication Date: 2015-01-21
SICHUAN HUAFENG ENTERPRISE GRP
View PDF2 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Moreover, taking the yellow passivation film as an example, after heating and drying processes such as printing and glue filling, the color of different batches of parts will change to varying degrees, so that the same set of products, such as the head and the same set of connectors There will be a large color difference between the seats
In addition, because cadmium and its thick passivation film are soft in texture, the corresponding wear resistance is poor, and it is easy to be scratched

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

[0024] The production process of the green passivation film of the cadmium-plated workpiece of the present embodiment is as follows:

[0025] ① Preparation of passivation solution

[0026] According to the amount of 1 liter of solution, the components of the passivation solution are:

[0027] Potassium dichromate 40g / l

[0028] Formic acid 60ml / l

[0029] Sulfuric acid 0.4ml / l

[0030] Phosphoric acid 0.01 ml / l

[0031] The balance is deionized water. Its preparation method is:

[0032] ② electroplating a cadmium layer with a thickness of 15 microns on the surface of the aluminum alloy workpiece to obtain a cadmium-plated workpiece; placing the cadmium-plated workpiece in the above-mentioned passivation solution and passivating it for 50 seconds at 18° C. to form a brown-yellow passivation film;

[0033] ③Put the cadmium-plated workpiece with a brown-yellow passivation film into an oven and bake at 220±2°C for 20±2 minutes to fix the color, and obtain a green passivation...

Embodiment 2

[0037] ① Preparation of passivation solution

[0038] According to the amount of 1 liter of solution, the components of the passivation solution are:

[0039] Potassium dichromate 45g / l

[0040] Formic acid 62ml / l

[0041] Sulfuric acid 0.6ml / l

[0042] Phosphoric acid 0.07 ml / l

[0043] The balance is deionized water. Its preparation method is:

[0044] ② Electroplating a cadmium layer with a thickness of 12 microns on the surface of the aluminum workpiece to obtain a cadmium-plated workpiece; placing the cadmium-plated workpiece in the above-mentioned passivation solution and passivating it for 55 seconds at 19° C. to form a brown-yellow passivation film;

[0045] ③Put the cadmium-plated workpiece with a brown-yellow passivation film into an oven and bake at 220±2°C for 20±2 minutes to fix the color, forming a matte green passivation film;

[0046] ④ Cool the above-mentioned workpiece prepared in step ③ to room temperature, then immerse it in water, then put it into th...

Embodiment 3

[0049] ① Preparation of passivation solution

[0050] According to the amount of 1 liter of solution, the components of the passivation solution are:

[0051] Potassium dichromate 50g / l

[0052] Formic acid 65ml / l

[0053] Sulfuric acid 0.8ml / l

[0054] Phosphoric acid 0.13 ml / l

[0055] The balance is deionized water. Its preparation method is:

[0056] 2. Electroplate a cadmium layer with a thickness of 18 microns on the surface of a common steel workpiece to obtain a cadmium-plated workpiece; place the cadmium-plated workpiece in the above-mentioned passivation solution and passivate it for 60 seconds at 21° C. to form a brown-yellow passivation film;

[0057] ③Put the cadmium-plated workpiece with a brown-yellow passivation film into an oven and bake at 220±2°C for 15±2 minutes to fix the color, forming a matte green passivation film;

[0058] ④ Cool the above-mentioned workpiece prepared in step ③ to room temperature, then immerse it in water, then put it into the m...

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
thicknessaaaaaaaaaa
Login to view more

Abstract

The invention discloses a process for producing a green passivation coating of a cadmium-plated workpiece. The process is characterized by comprising steps of performing passivation, color fixing, silicon sealing and solidification for the cadmium-plated workpiece. The process has the advantages that appearance and tone fluctuation during production is reduced, the uniform and consistent appearance of the passivation coating is guaranteed, and the produced green passivation coating is high in the salt spray corrosion resistance and good in heat stability; and after being subjected to silicon sealing, the coating is high in abrasion resistance, the conductivity of the passivation coating is unaffected, and the appearance of the passivation coating is unchanged.

Description

technical field [0001] The invention belongs to the technical field of electroplating, and in particular relates to a green passivation film production process for cadmium-plated workpieces. Background technique [0002] Cadmium plating is widely used in military products under marine climate conditions. Cadmium and light-weight aluminum alloys have excellent potential matching characteristics, which can avoid galvanic corrosion that easily occurs between other metals and aluminum alloys. Cadmium-plated products have extremely high resistance to salt spray corrosion, especially dark passivation films such as yellow, olive, and green, which can easily achieve neutral salt spray test resistance of products with aluminum alloy substrates for more than 500 hours. The appearance color of the chemical conversion film (passive film) of the cadmium plating layer varies with the composition of the passivation solution, the film-forming process in the solution, and the curing conditio...

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 Patents(China)
IPC IPC(8): C23C22/27C23C22/33
Inventor 张勇强陈凯高官荣
Owner SICHUAN HUAFENG ENTERPRISE GRP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap