2 pin 3 pin 4 pin 5 pin connector plug socket contact resistance detection function basic principle
Look at the surface of the 2-pin, 3-pin, 4-pin, 5-pin connector plug and socket contact parts under an optical microscope. Although the bronzing layer is very smooth, you can still observe a 5-10 mm protrusion. You will see the touch of the two touched parts that are mated, not all the touches on the surface, but the touches scattered at some points on the surface. The specific surface must be lower than the basic theoretical surface. Depending on the level of surface finish and the size of the contact pressure, the difference between the two can reach thousands of times. The specific surface can be divided into two parts; one is that the real metal material and the metal material immediately touch a part. That is, the contact micro-points without connection resistors between metal materials, also known as touching black spots, are generated after the page film is damaged by contact pressure or thermal effects. These account for approximately 5-10% of the total area touched. The second is the part that touches each other after polluting the plastic film on the page environment. Because all metal materials often have a tendency to return to the original compound.
In fact, no truly clean stainless steel passivation can be found in the air. Even very clean stainless steel passivation, if exposed to the air, will quickly transform into a few micrometers of early air oxide film. For example, if copper is 2-3 minutes, nickel is about 30 minutes, and aluminum takes only 2-3 seconds, its surface layer can produce a thin oxide film of about 2 mm in thickness. Even very smooth precious metal gold, because of its high surface, will produce layers of organic chemical gas adsorption film on its surface. In addition, floating dust in the air will also cause a build-up film on the surface of the contact. Therefore, from the external economic analysis, all surfaces are all environmental pollution.
2 pin 3 pin 4 pin 5 pin connector plug socket coating classification:
General aviation sockets are dominated by thiosulfate complexing agents; advanced types are dominated by organic compounds with non-sulfur content. The thickness of the full bright coating can exceed about 40μm, and the surface resistivity of the coating is ∽41μΩ? Cm. If Na3 [Au (SO3) 2] is used for the coating, the thickness of the gold layer can exceed 1.5μm. Bronzing on electronic ceramics.
2 pin 3 pin 4 pin 5 pin connector plug socket factory
2 pin 3 pin 4 pin 5 pin connector plug socket can also be used for buried hole plating of circuit board and non-conductor surface metallization. The use of cheap non-toxic polyphosphates eliminates harmful indoor formaldehyde and replaces them, but at the present stage there is no commercial product made by this coating method. With this coating method, the stacking speed can reach 3-4 μm / h, the service life can exceed about 10 circulation systems, and the coating has high density and brightness. It must also be continuously improved and developed in industry. Because the connection speed is slow, it is not suitable for places where frequent plug-in and fast connection are required.
The aviation socket uses alloy copper raw materials, which can be deepened for pre-plating and thickening, usually the coating reaches about 10 μm, and the chromaticity is as bright as the acid-base bright copper coating, which can exceed the actual effect of darkness when the blackening process is carried out.
Because Ni can cause allergic dermatitis, so the decorations contain Ni. EU member states have refused to import. When coating aviation sockets, palladium has become a common metal material. In the pure palladium plating process, the thickness is 0.1-0.2 μm; in the thick palladium plating process, the thickness is 3 μm, and cracks are not easy to occur. In order to prevent the coating from causing erosion or silver discoloration, white copper tin is applied on the surface.