Method for electroplating LED pin with high-gloss silver coating

Abstract

The invention relates to a method for electroplating an LED pin with a high-gloss silver coating. The method comprises the following steps: 1, adding the LED pin; 2, carrying out thermal degreasing and electric degreasing of the surface of the pin by sodium carbonate; 3, carrying out acid activation; 4, electroplating copper; 4, electroplating silver; and 6, carrying out cleaning, drying and protection treatment of the obtained coating, wherein the acid activation adopts a mixed solution containing 40-80g / L of hydrofluoric acid and 5-15g / L of sulfuric acid; the copper plating is two-step copper plating and comprises cyanide copper plating and copper sulfate plating; and the above silver plating technology is characterized in that materials used in the silver plating comprise 20-50g / L of silver nitrate, 140-200g / L of hydantoin, 30-70g / L of potash, 5-15g / L of boric acid, 120-140g / L of potassium citrate and 10-15mL of a brightener, silver plating is carried out at 20-100DEG C, the cathode current density is 0.1-2A / dm<2>, and a 99.99% pure silver plate is used as an anode. The method enables the gloss of the obtained coating to reach 1.7-1.8 in case and the extremely-thin silver coating (1mum) to be guaranteed, so demands of the subsequent welding quality and the conductive performance can be fully satisfied.

Description

technical field [0001] The invention relates to the technical field of electrodeposition, and relates to a method for electroplating high-gloss silver coatings on LED pins. Background technique [0002] As a new lighting technology, light emitting diode (Light Emitting Diode, LED) is a light emitting device that uses a semiconductor chip as a light emitting material to directly convert electrical energy into light energy. It is a cold light source with a very high photoelectric conversion rate, its energy consumption is only 1 / 8~1 / 10 of that of an incandescent lamp, and its service life can reach 100,000 hours. Since the birth of the world's first semiconductor light-emitting diode in the 1960s, with the improvement of technology and processing technology, LED has the characteristics of long life, energy saving, rich colors, safety, and environmental protection, and has been vigorously promoted by countries all over the world. Widely used in home, commercial or public place...