Preparation method of silver-coated aluminum powder

A technology of silver-coated aluminum and aluminum powder, which is applied in the direction of liquid chemical plating, coating, metal material coating technology, etc., and can solve problems such as cumbersome process, poor coating effect, and complicated treatment process

Inactive Publication Date: 2011-11-23
BEIJING UNIV OF TECH
View PDF5 Cites 24 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] (1) The pretreatment process of aluminum powder is complicated, and no method has been found to remove the oxide film on the surface of aluminum powder without affecting the surface quality of aluminum powder; (2) Aluminum is an amphoteric metal, and it requires a plating solution for chemical coating The environment is neutral, but the current silver plating formula often has too high pH value, the plating solution is unstable during the preparation process, the silver coating is not dense, and the coating effect is poor; (3) in the current silver plating chemical plating formula, the required chemical There are many raw materials, and some formulas use multiple silver plating, which is not conducive to the reduction of product cost. (4) The plating process is cumbersome and requires strict equipment, and the use of highly toxic substances such as cyanide also pollutes the environment more serious

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
  • Preparation method of silver-coated aluminum powder
  • Preparation method of silver-coated aluminum powder

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0036] Electroless copper plating:

[0037] Take 5g of 100μm spherical aluminum powder, add it to 10ml of acetone solution, ultrasonically clean it for 5 minutes to remove the grease on the surface, wash it with deionized water for 3 times, and filter it for later use. Take by weighing 1.2g anhydrous copper sulfate (at this moment aluminum powder and CuSO 4 The mass ratio is 5:1.2), disodium edetate 5.6g (CuSO 4 , EDTA-2Na molar ratio is 0.5), after dissolving with deionized water respectively, mix and place for 10 minutes to make it fully complexed. Add the pretreated aluminum powder to the above mixed solution, add 2 g of polyethylene glycol, adjust the pH value of the solution to 6 with hexamethylenetetramine-hydrochloric acid (pH=5.4), adjust the volume of the plating solution to 350 ml and raise the temperature to 30°C. Add 0.25g of solid sodium fluoride (the mass of sodium fluoride accounts for 5% of the mass of the powder), replace and plate for 30 minutes, stop stir...

example 2

[0041] Electroless copper plating:

[0042] Take 5g of 50μm aluminum powder, add it to 20ml of acetone solution, ultrasonically clean it for 10 minutes, remove the grease on the surface, wash it with deionized water for 3 times, and filter it for later use. Take by weighing 2.4g anhydrous copper sulfate (aluminum powder and CuSO 4 The mass ratio is 5:2.4), disodium edetate 5.6g (CuSO 4 , EDTA-2Na molar ratio is 1.0), after dissolving with deionized water respectively, mix and place for 10 minutes to make it fully complexed. Add the pretreated aluminum powder to the above mixed solution, add 2 g of gelatin, adjust the pH value of the solution to 4 with potassium hydrogen phthalate-hydrochloric acid buffer solution (pH=4), adjust the volume of the plating solution to 350 ml and heat up to 40°C, add 0.5g of solid sodium fluoride (the mass of sodium fluoride accounts for 10% of the mass of the powder), replace and plate for 30 minutes, stop stirring when the solution is clear, f...

example 3

[0046] Electroless copper plating:

[0047] Take 5g of 20μm aluminum powder, add it to 30ml of acetone solution, ultrasonically clean it for 10 minutes to remove the grease on the surface, wash it with deionized water for 3 times, and filter it for later use. Weigh 4.8g anhydrous copper sulfate aluminum powder and CuSO 4 The mass ratio is 5:4.8), disodium edetate 5.6g (CuSO 4 , EDTA-2Na molar ratio is 2.0), after dissolving with deionized water respectively, mix and place for 10 minutes to make it fully complexed. Add the pretreated aluminum powder to the above mixed solution, add 3g of gelatin, adjust the pH value of the solution to 7 with potassium hydrogen phosphate diformate-sodium hydroxide (pH=6.8), adjust the volume of the plating solution to 350ml and raise the temperature to 40 ℃, add 0.75g of solid sodium fluoride (the mass of sodium fluoride accounts for 15% of the mass of the powder), replace and plate for 30 minutes, stop stirring when the solution is clarified,...

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 relates to a preparation method of silver-coated aluminum powder and belongs to the technical field of powder surface treatment. The preparation method comprises the steps of performing copper displacement plating and then performing silver displacement plating. In the step of performing copper displacement plating, fluoride serves as a complexing agent of aluminum ions, so that reaction of removing an oxide film from the surface of aluminum powder can be performed in a nearly neutral environment, dissolution of the aluminum powder is inhibited and deposition of the copper on the aluminum powder is promoted. In the step of performing silver displacement plating, ammonium sulfate solution serves as activating solution, potassium sodium tartrate serves as a complexing agent ofcopper, and a copper platting layer is removed by replacing silver by copper, so that the silver can be deposited on the aluminum powder. The final silver-coated aluminum powder does not contain interlayer copper and the aluminum powder is coated completely. The procedures of plating the interlayer copper and then plating the silver are adopted, so the difficulty of coating the silver on the aluminum powder is reduced.

Description

technical field [0001] The invention belongs to the technical field of powder surface treatment, and relates to a method for coating silver on the surface of aluminum powder to obtain silver-coated aluminum powder. The prepared silver-coated aluminum powder has the characteristics of complete coating and good conductivity, and can be used as a conductive filler Conductive composite materials used in the electronics industry. Background technique [0002] With the development of electronic technology, various digital and high-frequency electronic appliances bring a lot of convenience to our life, but also bring a lot of electromagnetic pollution. Therefore, the research on electromagnetic shielding materials has very important practical significance. Electromagnetic shielding rubber is a very important electromagnetic shielding material, which is mainly composed of rubber and conductive filler. As a conductive filler, pure silver has excellent conductivity and oxidation res...

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): B22F1/02C23C18/40C23C18/42
Inventor 夏志东张星赵少凡高勇周虎郭福史耀武雷永平
Owner BEIJING UNIV OF TECH
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