Contact Material and Manufacturing Process
AgNi(30)C(3) contact material is made of silver, nickel, and graphite. It has good electrical conductivity and wear resistance. To further optimize their properties, researchers at
Fudar Alloy Materials have explored two main manufacturing processes: mechanical powder mixing and chemical coating.
1. Mechanical powder mixing method
Mix silver powder, nickel powder, and graphite powder together. Perform the initial rolling to shape the mixture. Sinter the shaped material in a hydrogen atmosphere. Finally, re-roll the finished product.
Features: Simple process, but uneven distribution of particles, the reinforcing phase is easy to agglomerate, affecting the comprehensive performance of the material.
2. Chemical coating method
Apply silver plating to the surface of nickel and graphite particles using chemical plating technology. Then, mix, sinter, and repress the materials.
Features: Uniform distribution of the prepared particles, the interface bound with the metallurgical state, significantly improving the comprehensive performance of the material.
Effect of Two Processes on Material Properties
1. Microstructure analysis
In materials made by the mechanical powder mixing method, nickel and graphite particles are unevenly distributed. This uneven distribution makes it easy for agglomerates to form, resulting in unstable material properties.
The chemical coating method ensures that nickel and graphite particles are uniformly distributed in the silver matrix. The reinforcing phase is fine and evenly dispersed.
Metallographic Organisation of AgNi30C3 Products Prepared by Different Processes
a—Mechanical Powder Mixing Method；b—Chemical Coating Method
2. Fracture Morphology
The fracture of the mechanical mixing method is brittle, the reinforcing phase is easy to fall off, and the interfacial bonding strength is low.
The fracture in the chemical coating method shows tearing ribs and tough sockets. It has higher interfacial bonding strength, and the crack extension is effectively hindered.
SEM Photographs of Fracture of AgNi30C3 Products Prepared by Different Processes
a—Mechanical Powder Mixing Method； b—Chemical Coating Method
3. Comparison of physical properties
Density: The material made by the chemical coating method has a higher density. During the sintering process, the densification of the particle interface is more thorough.
Hardness: The hardness of the chemically coated material is higher. The uniform distribution of the particles enhances the pinning effect of the reinforcing phase.
Resistivity: The resistivity of chemically coated materials is lower and the conductive network is more complete.
Effect of Different Preparation Processes on the Physical Properties of AgNi30C3
a--Density Comparison； b--Hardness Comparison； c--Hardness Comparison
Advantages of the Chemical Coating Method
The study results show that the AgNi(30)C(3) contact materials made by the chemical coating method exhibit significant improvements. Key properties such as hardness, density, and resistivity are enhanced compared to those made by the mechanical powder mixing method. This is mainly due to the more uniform particle distribution and higher interfacial bond strength. These factors provide a more reliable solution for intelligent air circuit breakers.
Future Perspective
With the rapid development of the smart grid and low-voltage electrical market, the requirements for contact material performance will be further improved. In the future, optimizing the process parameters of the chemical coating method will be crucial. Exploring new compound materials will also play an important role in enhancing the performance of intelligent air circuit breakers.
Through in-depth research on the preparation process, AgNi(30)C(3) contact materials demonstrate their strong performance potential. In the era of intelligence, these technological innovations will provide strong support. They will ensure the safety and reliability of power systems. For more info about Fudar solutions, or to schedule a consultation with our experts, don't hesitate to get in touch.
