Reducing the amount of precious metals and improving material properties has always been an eternal research direction in the field of electrical contact materials. The above needs also exist in the field of the fuses. The fuses are one of the major categories of thermal fuses. As one of the components of the fuse, the star-shaped reed is mainly made of silver-based electric contact material.

    In terms of reducing the amount of precious metals, there are three main development trends:

    ① The thickness of the star-shaped reed material is reduced. Movable contact materials should have better plasticity and strength, as well as better high-temperature stability.

    ② Development of silver-based materials with low silver content. Representative materials such as internal oxidation process AgCuO (20) materials, or even silver-based materials with lower silver content.

    ③ The softening temperature of the middle layer of the composite material increases and the thickness of the cladding layer decreases. The middle Cu layer can be replaced with high-strength and high-conductivity copper alloy to increase the overall softening temperature of the material and reduce the thickness ratio of the surface silver metal oxide layer, thereby reducing the amount of precious metal while meeting the usage requirements.

    Improving material performance is mainly in the form of pairing. The subsequent development direction is to add a silver metal oxide material layer to the end of the lead that is in direct contact with the star-shaped reed to form a pairing structure between silver metal oxide and silver metal oxide, and improve the welding resistance and arc burning resistance between the two.

——The content of the article comes from the Internet