TOKYO, Nov 26, 2015 – Tanaka Holdings Co., Ltd. (Head office: Chiyoda-ku, Tokyo; Representative Director & CEO: Akira Tanae) announced today that the manufacturing business of the Tanaka Precious Metals, Tanaka Kikinzoku Kogyo K.K. (Head office: Chiyoda-ku, Tokyo; Representative Director & CEO: Akira Tanae) has successfully developed CDF-10, a cadmium-free electrical contact material used primarily in vehicles and smartphones with improved sliding wear resistance*1 compared to existing products. It has developed a system of mass production and will start full-scale operations on December 1.
Background to development of clad materials for electrical contacts
One type of electrical contact material, clad material, uses a different high electrical conductivity contact metal bonded only to the points of contact on a comparatively inexpensive base metal. Clad material enables reduced amounts of contact metal, which functions sufficiently at a thickness of a few dozen microns at the contact points. So clad electrical contacts are an inexpensive material while also having high sliding wear resistance.
In the contact materials market, precious metals have been essential materials for clad material contact points used in components that demand high reliability, such as automotive air conditioner damper motors, with silver-copper-nickel alloys (AgCuNi). In 1993, Tanaka Kikinzoku Kogyo developed CDF-2 for this market, as a modified AgCuNi alloy with improved sliding wear resistance, and it is currently one of Tanaka’s core electrical contact products, alongside AgCuNi. However, with even higher market requirements over recent years, development of even longer-life, inexpensive products have become an issue for the company.
Properties of CDF-10 cadmium-free clad material for electrical contacts
The main component of this successfully developed CDF-10 is AgCuNi, to which fine 1-2um deposited particles have been added to control adhesive wear*2 during sliding. The sliding wear rate of CDF-10 is one-fifth that of AgCuNi and one-half that of CDF-2, and when applied at the same thickness, it achieves more than twice the life of either. In other words, CDF-10 enables the same performance to be maintained at half the current thickness, meeting customer needs for thinner contact materials. This technology enables cost reductions of about 20-40 percent for customers developing products that use clad material for electrical contacts.
Future initiatives with mass production of CDF-10
Tanaka Kikinzoku Kogyo boasts the world’s largest share of precious metal clad material production, at over 40 percent share, and as a leading company in this field, it is continuing development to provide electrical contact material that meets the various needs of its customers. Going forward, it aims to further expand its share in markets for highly versatile micro-motors, switches and connectors through their use with smartphones and consumer electronics in addition to automotive air conditioner damper motors and various sensors. Tanaka Kikinzoku Kogyo is targeting yearly sales of CDF-10 worth 500 million yen by 2018.
