Passivation method of easy-to-cover black trivalent chromium for plating and coating combination

A trivalent chromium, cladding technology, applied in liquid chemical plating, coating, metal material coating process and other directions, can solve the problems of high production cost and poor bonding force, reduce varieties, improve standardization level, reduce The effect of production costs

Pending Publication Date: 2022-03-22
DONGFENG MOTOR FASTENER CO LTD
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] In order to solve the problem of poor bonding between the trivalent chromium black passivation film and the silane-based top coat and the prob

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Passivation method of easy-to-cover black trivalent chromium for plating and coating combination
  • Passivation method of easy-to-cover black trivalent chromium for plating and coating combination

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0022] Embodiment 1: a kind of coating combination is easy to cover type black trivalent chromium passivation method, and concrete steps are as follows:

[0023] The first step of degreasing: use a degreasing agent to remove the oil on the surface of the workpiece, and wash the workpiece with water after degreasing; the degreasing agent is FS-251, the concentration of the degreasing agent is 10%, the balance is water, and the degreasing temperature is 60°C. Degreasing time is 15 minutes;

[0024] The second step pickling: remove the oil-stained workpiece and carry out pickling to remove the scale on the surface of the workpiece; after pickling, the workpiece is washed with water; the pickling solution is hydrochloric acid, and the concentration of the pickling solution is 18%, and the balance is water , pickling time is 8 minutes;

[0025] The third step of galvanizing: coat a layer of zinc on the surface of the workpiece, and wash the workpiece with water after galvanizing; ...

Example Embodiment

[0028] Embodiment 2: a kind of coating combination is easy to cover type black trivalent chromium passivation method, concrete steps are as follows:

[0029] The first step of degreasing: use a degreasing agent to remove the oil on the surface of the workpiece, and wash the workpiece with water after degreasing; the degreasing agent is FS-251, the concentration of the degreasing agent is 15%, the balance is water, and the degreasing temperature is 70°C. The degreasing time is 17 minutes;

[0030] The second step of pickling: remove the oil-stained workpiece and carry out pickling to remove the scale on the surface of the workpiece; after pickling, the workpiece is washed with water; the pickling solution is hydrochloric acid, the concentration of the pickling solution is 20%, and the balance is water. Pickling time is 10 minutes;

[0031] The third step of galvanizing: coat a layer of zinc on the surface of the workpiece, and wash the workpiece with water after galvanizing; t...

Example Embodiment

[0034] Embodiment 3: a kind of coating combination is easy to cover type black trivalent chromium passivation method, concrete steps are as follows:

[0035] The first step of degreasing: use a degreasing agent to remove the oil on the surface of the workpiece, and wash the workpiece with water after degreasing; the degreasing agent is FS-251, the balance is water, the concentration of the degreasing agent is 12%, and the degreasing temperature is 65 ° C. Degreasing time is 20 minutes;

[0036] The second step of pickling: remove the oil-stained workpiece and carry out pickling to remove the scale on the surface of the workpiece; after pickling, the workpiece is washed with water; the pickling solution is hydrochloric acid, the concentration of the pickling solution is 23%, and the balance is water. Pickling time is 12 minutes;

[0037] The third step of galvanizing: coat a layer of zinc on the surface of the workpiece, and wash the workpiece with water after galvanizing; the...

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

No PUM Login to view more

Abstract

The invention discloses a passivation method of easy-to-cover black trivalent chromium for plating and coating combination. The passivation method comprises the following specific steps: step 1, degreasing and washing; step 2, pickling and washing; step 3, galvanizing and washing; step 4, passivating and washing; and step 5, spin-drying. Passivating the surface of the workpiece by adopting an easy-to-cover passivating agent, and washing the passivated workpiece with water; the easy-to-cover passivator is formed by mixing an agent A and an agent B, the agent A is prepared from the following raw materials: complexing liquid, cobalt sulfate, ferrous sulfate and nickel sulfate; the complexing solution is composed of chromium sulfate and sodium oxalate; the agent B is prepared from the following raw materials: phosphoric acid concentration, nitric acid concentration, malic acid concentration, sodium benzoate concentration and disodium hydrogen phosphate concentration; according to the invention, a layer of silane top coat is coated on the galvanized passivation film, so that the advantages of various types of galvanization, Dacromet, phosphorization and the like can be combined together, various existing surface treatment processes are replaced, the variety of fasteners is reduced, the standardization level of parts is improved, and the production cost is reduced.

Description

technical field [0001] The invention belongs to the field of metal surface treatment, in particular to an easy-to-coat black trivalent chromium passivation method for plating and coating combinations. Background technique [0002] The surface treatment processes of small-sized parts (such as fasteners, small brackets, etc.) for domestic and foreign automobiles mainly include galvanizing, phosphating, dacromet, and zinc-nickel alloy. [0003] The corrosion resistance of phosphating is poor, and the neutral salt spray test is generally 24 hours; Dacromet and zinc-nickel alloys have good salt corrosion resistance, which can reach more than 480 hours, and are suitable for applications in areas where roads often melt snow or marine climates. Acid rain corrosion resistance is relatively poor (sulfur dioxide gas corrosion test for 24 hours) is easy to corrode in inland areas; galvanized acid rain corrosion resistance is better (sulfur dioxide gas corrosion test for 72 hours), suita...

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
IPC IPC(8): C23C22/47C23C18/31
CPCC23C22/47C23C18/31
Inventor 李才红刘平保王宗广陈中祥
Owner DONGFENG MOTOR FASTENER CO LTD
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