The Great Contact Material Upgrade! How Ultrasonic Dispersion Revolutionises AgZnO Contact Properties?

Limitations of the Traditional AgZnO Preparation Process

The mechanical powder mixing method is a commonly used technique for preparing AgZnO. It is widely adopted due to its short production cycle and relatively simple operation.

However, this method has a significant drawback. The ZnO powder is extremely fine and tends to agglomerate. As a result, it cannot be uniformly dispersed within the silver matrix. This unevenness causes changes in material properties. These changes affect the stability and lifespan of the contacts.

Breakthrough in Ultrasonic Dispersion

Ultrasonic dispersion uniformly disperses ZnO particles in a silver matrix through a physical phenomenon known as the ‘cavitation effect’. Specifically, when ultrasonic vibrations are transmitted through a liquid, tiny bubbles form within the liquid.

When these bubbles burst, tiny fluid shock waves are generated. These shock waves disperse the larger ZnO particles into smaller ones, effectively preventing the agglomeration of ZnO. This process improvement results in a more uniform and stable internal structure of the AgZnO contact material. As a result, the comprehensive performance of the material is significantly enhanced.

Performance Comparison: Advantages of Ultrasonic Dispersion

AgZnO materials prepared using ultrasonic dispersion are superior in several ways:

Higher density: AgZnO materials prepared by ultrasonic dispersion are denser. This is because the homogeneous dispersion of ZnO particles facilitates a denser structure during the sintering process. In contrast, the mechanical mixing method results in more pores and lower density due to the agglomeration of ZnO particles.

a—Mechanical Powder Mixing 500x	b—Ultrasonic Dispersion 500x
c—Mechanical Powder Mixing 5000x	d—Ultrasonic Dispersion 5000x

SEM Fracture Morphology of AgZnO Products Prepared by Different Processes

Lower electrical resistivity: The electrical conductivity of the material depends on the area of the internal Ag-Ag conductive network. Ultrasonic dispersion increases this conductive network, resulting in a significantly lower resistivity and better conductivity.

Higher hardness: The increase in hardness is caused by the reinforcement of the silver matrix. This reinforcement occurs due to the fine and uniformly distributed ZnO particles. This phenomenon is called "second-phase strengthening." It gives AgZnO materials made by ultrasonic dispersion a big advantage in mechanical properties.

Better fracture strength: Fracture analysis shows that the AgZnO material, prepared by the ultrasonic dispersion method, has strong internal bonding. This makes it less prone to brittle fracture under external force and gives it excellent toughness.

Ultrasonic Dispersion Method Brings Application Prospects

With the increasing demand for environmentally friendly and high-performance electrical contact materials, ultrasonic dispersion has a promising future. The advantages of this process are twofold. First, it improves the material performance. Second, it provides a low-cost, high-quality solution for producing electrical contact materials.

In the future, high-dispersion AgZnO contact materials, prepared by ultrasonic dispersion, will play a key role in improving the performance of relays and circuit breakers. They will also contribute to the environmental protection of such equipment. For more information about the AgZnO and related solutions or products, please visit https://www.fudarworld.com/ or feel free to contact us.