Conductors made of copper and copper alloys are frequently electroplated with pure metal coatings like Tin, silver, and nickel. In some circumstances, numerous layers of alloy coatings such as tin/lead (solder coat) or composite coatings such as silver over nickel, etc., can be applied. Coatings are used to improve the conductor’s performance.
When applied as a pure metal coating, Tin raises the working temperature of copper conductors to 150 degrees Celsius and improves solderability. Tin plating is relatively inexpensive in comparison to the performance gains it provides. It’s mainly used because of its temperature and solderability properties.
Tin plating is only utilised on base materials that are not subjected to high-temperature processing after the Tin is applied due to the Tin’s low melting temperature. Some high-strength copper alloys and other base materials require heat treatment or anneal to melt the tin coating during processing.
Solderability of tin-plated copper conductors has a finite shelf life. Tin and copper interact over time and at a rate regulated by temperature to generate an intermetallic alloy. The conductor loses its solderability when all of the Tin on the surface has been consumed (alloyed with the base copper). Even at room temperature, this reaction happens and is unaffected by protective packaging. Solderability is also harmed by surface oxidation, so the conductor should be packaged to protect it from air and moisture. Proper packaging and storage in a temperature-controlled environment can extend shelf life.
silver plating for equipment
Silver plating for equipment raises the operating temperature of copper or copper alloy conductors to 200 degrees Celsius. The conductor also has a high solderability due to the silver coating. If conventional packaging measures are employed to preserve the surface from oxidation, silver will retain its solderability. Due to diffusion, its solderability will not deteriorate over time.
The electrical conductivity of pure silver is the highest of any pure metal. Silver plating for equipment a conductor also increases the wire’s high-frequency transmission properties. The “skin effect” occurs when high-frequency electrical signals flow down the conductor’s surface, and employing silver for that pathway improves the conductor’s performance.
Silver is a soft metal with a low contact resistance due to its electrically conductive oxide. As a result, silver-plated conductors for crimp terminations have numerous advantages over alternative Silver plating for equipment. According to ASTM B 298, silver-plated conductors must have a minimum plating thickness of 40 micro-inches (0.000040 inches) (equal to 1 micron). Depending on the use, thickness variations are acceptable.
A barrier layer between the surface and the base metal is created by Silver plating for equipment of different metals’ base metal. This reduces intermetallic interaction between the surface and the base metal while preserving the surface Silver plating for equipment beneficial qualities.
Thickness Measuring Techniques
Electrochemical methods are used to determine the plating thickness of conductor strands. An electronic thickness tester that uses an electrochemical de-plating approach (often referred to as the “Kocour” method—named after an equipment manufacturer) is recognised by ASTM (B 33, B 298, and B 355). To measure the plating thickness, this coulometric technique uses a controlled “de-plating” current rate, the time necessary to remove the plating material, and the diameter and length of the sample area.
Silver plating for equipment integrity can be measured in terms of plate continuity and adhesion to the base metal.
Continuity of Coating
The plating material must completely cover the wire’s surface, according to the specifications. When viewed with the naked eye before stranding, base metal exposure is unsatisfactory. To make this testing more accessible, samples are treated with a sodium polysulfide solution (ASTM B 33, B 298, and B 355), darkening any exposed copper regions.
The base metal must be adhered to by the plated layer. Stress is first applied to the Silver plating for equipment interface in adhesion testing. Twisting two-conductor lengths together or winding a conductor length around its own diameter puts enough stress on the plated layer that any areas of poor adhesion show up as lifting or cracking. A sodium polysulfide test is then performed on the samples. Blackened exposed copper sees poor adhesion.
Silver plating for equipment is available at smart microns in thicknesses ranging from 1 micron to 20 microns. Despite its noble status, silver is subject to oxidation and eventual corrosion. We offer lacquering services ranging from light to hard lacquer, depending on the usage and exposure time of the plated component or product.