Industrial copper plating can be classified as the following table according to the types of plating bath.Physical properties of the coating to be deposited vary depending on the types of plating bath. It is important to choose an appropriate type according to the intended use.
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The following diagram shows the properties of plating films formed by using various types of plating bath.
Industrial materials used as non-conducting substances include plastics, rubbers, and ceramics. This lesson introduces plating on ceramics.
Ceramics are used for electrical components and semiconductor parts for its superior electrical insulation, high frequency characteristics, heat resistance, thermal conductivity and more. However, to use ceramics in electrical applications, a part of the ceramics must be metalized in order to allow formation of necessary electrodes and circuits.
Ceramics can be metalized by various methods from metal deposition and sputtering to a baking process using silver paste. Considering the reliability in terms of adhesion and precision, it is best to adopt the electroplating method.
The common procedure is as follows:
Degreasing → Surface Conditioning → Etching → Catalyzing →
Electroless Plating → Electroplating
As you can see, the ceramic plating process is basically same as the plastic plating process. The difference here is the type of solution used. [Table] lists the purposes and applications of plating used for electrical components.
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The primary purposes of plating on plastic materials were to add decorative elements such as luxurious feel achieved by the metal-textured surface, as well as to prevent degradation of the plastic resin.
For the automobile components, polyacetal was used in place of zinc die cast, while nylon and polycarbonate resin were adopted in place of steel.
In today's IT era, electroless copper/nickel plating is applied on polycarbonate computer housings, keyboards, connector hoods and more, in order to protect these devices from electromagnetic waves.
Examples of the electroplating application also include circuit boards, connectors, and IC testers that are made of heat-resistant special engineering plastics or super engineering plastics, adding superior bonding and soldering properties.In this case, the plating adhesion must be high.The general process of plating on plastic materials is as follows:
Degreasing -> Etching -> Catalyzing -> Electroless Plating -> Electroplating
The etching process corrodes the plastic surface and selectively dissolves out butadiene using concentrated chromium acid or sulfuric acid to prepare the material for the next process where strong metal catalysts are formed.
Catalyzing is a process in which catalytic nuclei (Au, Ag, Pt, Pd, etc.) necessary for the next electroless plating are deposited onto the plated material.
The electroless plating is designed to add conductivity to plastic materials by applying copper or nickel plating over them, using electroless plating solution containing chemical reducing agent, which acts as electricity used in electroplating.This process prepares the material for the next electroplating step.
The following table describes the characteristics and precautions specific to other metals being plated that were not introduced in the previous lessons.
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