Posted on 9/21/2026 by Fudar Offical | Views: 149
Electrical contacts make, carry, and interrupt current in switches, relays, contactors, and circuit breakers. Silver-based contact materials are widely used for their conductivity and reliable switching performance, but their cost has driven interest in copper-based alternatives.
Copper is highly conductive and can be more cost-effective than silver. However, exposed copper oxidizes readily, while repeated arcing can accelerate material loss. Both effects can increase contact resistance and shorten electrical life.
To address these challenges, Fudar Alloy developed a graphene-coating process for copper-based electrical contact materials. The process is designed to protect the copper-rich matrix while preserving its conductivity.
Conventional copper-based formulations often use reinforcing particles or alloying additions to improve electrical contact performance. However, these additions do not necessarily protect the copper matrix itself. When graphene or carbon nanotubes are introduced only through mechanical mixing, they may be distributed unevenly. Some copper surfaces can remain exposed, while the carbon and reinforcing particles may cluster elsewhere.
Fudar's approach forms graphene directly on the surface of the copper or copper-alloy powder before consolidation. The coating is no more than 10 nanometers thick and covers 50 to 100 percent of the particle surface area.
Placing the carbon phase around the conductive matrix at the powder stage is intended to reduce copper exposure and distribute the oxide and carbide reinforcements more evenly.
The material combines a graphene-coated, copper-rich matrix with selected oxide and carbide powders. The composition ranges and coating parameters are summarized below.
| Component | Specified Range or Parameter | Role in the Material |
| Graphene-coated copper or copper-alloy powder | Balance | Conductive matrix with particle-level surface protection |
| Oxide powder | 0.01–10 wt% | Reinforcing phase |
| Carbide powder | 0.01–2 wt% | Reinforcing phase |
| Graphene coating | Up to 10 nm thick; 50–100% surface coverage | Nanoscale carbon layer on the matrix particles |
The oxide phase may include one or more of SnO₂, CuO, ZnO, Fe₂O₃, and rare-earth oxides. Carbide options include WC, VC, and B₄C.
The matrix may be pure copper or a copper alloy containing more than 95 wt% copper. Possible alloy systems include CuAl, CuZn, CuNi, CuB, CuTe, copper–rare-earth alloys, and multi-element copper alloys.
The material is produced in three main stages.
1. Coat the copper-rich powder
A graphene layer is formed on the surface of the copper or copper-alloy particles by chemical vapor deposition or liquid-phase reduction of graphene oxide.
2. Prepare the powder blend
The graphene-coated matrix powder is mixed with the selected oxide and carbide powders in the required proportions.
3. Consolidate the material
The blend is either compacted into a billet, sintered, and extruded, or die-pressed, sintered, and repressed. Both representative formulations presented below were produced by isostatic pressing, sintering, and extrusion.
The material design targets four related aspects of contact performance.
Fudar Alloy developed two representative formulations to demonstrate how the graphene-coating process can be applied to both a high-copper CuTe alloy and pure copper.
| Property | CuTe formulation | Copper formulation |
| Matrix | Graphene-coated CuTe alloy | Graphene-coated copper |
| Matrix composition | Cu 99.5 wt%; balance Te | Pure copper |
| Reinforcements | 1 wt% WC; 1 wt% SnO₂ | 0.5 wt% B₄C; 0.3 wt% SnO₂ |
| Graphene-coating route | Liquid-phase reduction of graphene oxide | Chemical vapor deposition using methane |
| Consolidation route | Isostatic pressing, sintering, and extrusion | Isostatic pressing, sintering, and extrusion |
| Density | 8.78 g/cm³ | 8.72 g/cm³ |
| Resistivity | 2.18 µΩ·cm | 2.06 µΩ·cm |
| Hardness | HV108 | HV93.5 |
These examples show that both graphene-coating routes can be integrated with powder consolidation. However, the reported data cover only density, resistivity, and hardness. Device-level switching results are not included, so the values demonstrate material and process feasibility rather than confirmed performance in a finished contact system.
Fudar's graphene-enhanced copper-based material is intended for low-voltage circuit breakers, contactors, and relays. The material platform can use either pure copper or a copper-rich alloy with selected oxide and carbide reinforcements, allowing the composition to be adapted to different application requirements.
The material is designed for specific switching duties rather than as a direct replacement for every silver-based contact. Its composition and manufacturing process should be matched to the application, and the final contact should be validated under the intended electrical and operating conditions.
To discuss graphene-enhanced copper contact materials for your application, contact Fudar Alloy team.
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