Electrical Contacts and CuW
Mi-Tech developed CuW materials to be used in oil-filled devices, air and gas circuit breakers, contactors, and high voltage switch gears. Some common applications are arcing contacts and plates, arc runners, current carrying members and blade facings.
CuW metal composites have excellent arc resistance properties, which minimizes arc erosion and transfer problems. The high electrical and thermal conductivity allows a cooler and more effective transfer of power.
These characteristics can be varied by composition—more silver or copper yields higher electrical and thermal conductivity, while a higher refractory metal content results in superior arc erosion properties.
All of our materials are produced by the press, sinter, and infiltrate process. Each manufacturing step, including the basic powder, is closely controlled and monitored. Quality Assurance signs off on each step. After completion, all manufactured lots are checked for conductivity, density, and hardness prior to shipping. This information is recorded and kept on file and also accompanies the parts or materials when requested.
We specialize in the manufacturing of large size contacts. We routinely produce 4" x 8" rectangles and 3" diameters in most commonly-used contact materials. For smaller quantity requirements, contacts can be manufactured from our standard stock bar.
Mi-Tech also has the ability to produce individual shapes and sizes. Our machining abilities allow us to machine to print small parts as well as large parts.
We're a primary supplier to electrical device rebuilders and to original equipment manufacturers. We stock most commonly used sizes and materials.
| Mi-Tech | Nominal Composition % Weight | Rockwell Hardness | Electrical Conductivity % IACS | Density GMS/CC |
| CuW 68 | 68% Tungsten & 32% Copper | 88 B | 52 | 13.93 |
| CuW 70E | 68% Tungsten & 32% Copper | 88 B | 52 | 13.93 |
| CuW 70 | 70% Tungsten & 30% Copper | 90 B | 50 | 14.18 |
| CuW 75 | 75% Tungsten & 25% Copper | 94 B | 48 | 14.7 |
| CuW 80 | 80% Tungsten & 20% Copper | 98 B | 44 | 15.56 |
| SW 50 | 50% Tungsten & 50% Silver | 70 B | 65 | 13.4 |
| SW 65 | 65% Tungsten & 35% Silver | 87 B | 53 | 14.5 |
| SW 74 | 74% Tungsten & 26% Silver | 90 B | 47 | 15.5 |
| TCS50 | 50% Tungsten carbide & 50% Silver | 79 B | 47 | 12.2 |
| TCS60 | 60% Tungsten carbide & 40% Silver | 95 B | 40 | 12.8 |
| SM50 | 50% Molybdenum & 50% Silver | 75 B | 50 | 10.2 |
| SM60 | 60% Molybdenum & 40% Silver | 80 B | 47 | 10.2 |
