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

Method for plating decorative chromium by die-cast zinc alloy part

A zinc alloy and coating technology, which is applied in the field of decorative chrome plating of die-cast zinc alloy parts, can solve the problems of poor bonding between the nickel coating and the substrate, limited application range, and restrictions on large-scale applications, etc., and achieves metal coating methods that are simple, The effect of low production cost and improved binding force

Inactive Publication Date: 2016-04-20
张颖
View PDF3 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] Neutral nickel pre-plating is mainly used for the rack plating process of zinc alloy die castings, and the main component of the plating solution is NiSO 4 , sodium citrate, etc., do not contain cyanide, but the bonding force between the nickel plating layer and the substrate is far inferior to the performance of cyanide copper plating pre-plating, and the product qualification rate is low
Moreover, due to the poor activation ability of the neutral nickel plating solution on zinc alloy die castings, there are higher requirements for its pretreatment
The neutral nickel plating process generally cannot be used for barrel plating of zinc alloy die castings, therefore, the range of industrial applications is not very wide
In addition, the cost of neutral nickel plating solution is high, and wastewater treatment is difficult, which limits its large-scale application in industry.
[0007] Other zinc alloy die casting pre-plating processes include chemical copper plating, HEDP copper plating, copper-tin alloy electroplating, etc., all of which have not been practically applied in industry due to problems such as bonding force, cost, and wastewater treatment.

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

[0027] A method for decorative chrome plating of die-cast zinc alloy parts, said method comprising the steps of:

[0028] (1) Pre-plating treatment: including surface degreasing and degreasing, pickling and derusting, and activation treatment to improve the bonding force of the coating; the surface degreasing and degreasing is the use of acetone ultrasonic degreasing and alkali washing degreasing process, alkali washing The solution composition and process of degreasing are: Na 2 CO 3 10H 2 O35g / L, Na 3 PO 4 12H 2 O20g / L, sodium lauryl sulfate 0.6g / L, temperature: 64°C, time: 6min; use pickling solution for pickling, the composition and process of the pickling solution is CrO3 150g / L, HNO 3 (68%) 130ml / L, the temperature is room temperature, and the treatment time is 3 minutes; the activation solution is used for activation, and the composition and process of the activation solution are: HF (40%) 400mL / L, the temperature is room temperature, and the time is 7 minutes;

...

Embodiment 2

[0036] A method for decorative chrome plating of die-cast zinc alloy parts, said method comprising the steps of:

[0037] (1) Pre-plating treatment: including surface degreasing and degreasing, pickling and derusting, and activation treatment to improve the bonding force of the coating; the surface degreasing and degreasing is the use of acetone ultrasonic degreasing and alkali washing degreasing process, alkali washing The solution composition and process of degreasing are: Na 2 CO 3 10H 2 O45g / L, Na 3 PO 4 12H 2 O18g / L, sodium lauryl sulfate 0.8g / L, temperature: 60°C, time: 10min; use pickling solution for pickling, the composition and process of the pickling solution are CrO 3 130g / L, HNO 3 (68%) 150ml / L, the temperature is room temperature, and the treatment time is 2 minutes; the activation solution is used for activation, and the composition and process of the activation solution are: HF (40%) 420mL / L, the temperature is room temperature, and the time is 5 minutes;...

Embodiment 3

[0045] A method for decorative chrome plating of die-cast zinc alloy parts, said method comprising the steps of:

[0046] (1) Pre-plating treatment: including surface degreasing and degreasing, pickling and derusting, and activation treatment to improve the bonding force of the coating; the surface degreasing and degreasing is the use of acetone ultrasonic degreasing and alkali washing degreasing process, alkali washing The solution composition and process of degreasing are: Na 2 CO 3 10H 2 O40g / L, Na 3 PO 4 12H 2 O19g / L, sodium lauryl sulfate 0.7g / L, temperature: 62°C, time: 8min; use pickling solution for pickling, the composition and process of the pickling solution is CrO 3 140g / L, HNO 3 (68%) 140ml / L, the temperature is room temperature, and the treatment time is 2.5 minutes; the activation solution is used for activation, and the composition and process of the activation solution are: HF (40%) 410mL / L, the temperature is room temperature, and the time is 6 minutes;...

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 method for plating decorative chromium by a die-cast zinc alloy part. The method comprises the steps of: (1) treatment before plating ; (2) cyanide-free copper preplating; (3) acid copper plating; (4) electroplating of semi-bright nickel; (5) electroplating of high-sulfur nickel; (6) electroplating of bright nickel; and (7) electroplating of chromium. An obtained plating layer is uniform in plating film thickness, high in corrosion resistance, high in hardness, bright and smooth in surface, free of generation of scales, peeling, fading and color changing and suitable for decorative chromium plating treatment of decorative parts, artware and the like.

Description

technical field [0001] The invention relates to the field of electroplating, in particular to a method for decorative chrome plating of die-cast zinc alloy parts. Background technique [0002] Due to its cheap price, low melting point, and especially good die-casting process performance, zinc alloy has been widely used in the manufacture of small hardware accessories, and can also be used to manufacture decorative and practical metal parts. Such as various zippers, belt buckles, luggage accessories, car nameplates and military badges, etc. [0003] The appearance of zinc alloy die castings is gray and white, and there are various defects on the surface, such as: slag inclusions, shrinkage cavities, etc. Therefore, without surface treatment, its usability and decoration are very poor. A common surface treatment method is electroplating. According to the different decorative and functional requirements, there are certain differences in the electroplating process. For exampl...

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): C25D5/14C25D5/34
CPCC25D5/14C25D5/34
Inventor 张颖
Owner 张颖
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