Silver-based electrical contact material is the core component in electrical products. With the continuous expansion of the application range, the performance requirements are also increasing - the contact material cannot be fused during the breaking process, and cannot produce too high temperature rise; maintain a low and stable resistance during contacting; high wear resistance and etc.
Because the AgCdO material can decompose heat absorption and arc extinguishing at high temperatures, its electrical life is long. Known as "universal contacts", AgCdO also has low and stable contact resistance, and good the processing performance. It's active in a variety of small current to large current switches, relays, contactors and other electrical contact devices. However, AgCdO material has a fatal disadvantage that it is easy to produce Cd vapor, and it will cause Cd poisoning after inhalation, affecting body functions, causing damage, and affecting the environment. Therefore, some countries in Europe have introduced laws and regulations to prohibit the use of CD-containing contact materials in household appliances.
Silver nickel the most common electrical contact material used in contactor and relays. It has good electrical and thermal conductivity, low resistivity and temperature rise. And it also has good ductility and cutting ability, short processing cycle, low cost advantages. It's widely used in high-precision, high-sensitive communications, electronics, automotive and other industries and fields.
However, there is no infiltration between silver and nickel, and the interface between silver and nickel produced by conventional powder metallurgy method is simple mechanical contact. And the machinability becomes worse and worse with the increase of nickel content. Periodic cracks will inevitably appear in the production of silver-nickel materials with high nickel content, which not only affects the machinability of the materials, but also affects the machinability of the materials. And it will further affect the electrical properties of the material.
In order to improve the interface of the two powders, the transition element is coated on the surface of the nickel powder by the method of combining chemistry and mixing powder, so as to solve the problem that both powders are not infiltrated.
This method makes the surface of nickel powder more rounded, improves the interface between silver powder and nickel powder, and is no longer a simple mechanical contact; The processing properties of silver nickel materials are improved, especially the elongation is greatly improved, and the electrical properties are better.
Post time: Apr-26-2024