Tubular ceramic dielectric capacitor electrode manufacturing method based on chemical nickel plating and tin electroplating

Abstract

The invention discloses a tubular ceramic dielectric capacitor electrode manufacturing method based on chemical nickel plating and tin electroplating. The manufacturing method comprises the steps of coarsening a fired ceramic tube after being subjected to extrusion or dry pressing molding; carrying out high-temperature activation on the ceramic tube; carrying out sodium hypophosphite solution activation on the ceramic tube; carrying out chemical nickel pre-plating on the ceramic tube; carrying out hydrochloric acid activation on the ceramic tube for the first time; carrying out chemical nickelplating on the ceramic tube; carrying out the hydrochloric acid activation on the ceramic tube for the second time; thickening the nickel plating on the ceramic tube; carrying out tin electroplatingtreatment on the ceramic tube; grinding off the two ends of the ceramic tube to expose a ceramic matrix; and checking and testing the electrical performance of the ceramic tube, and then completing the manufacture of the tubular ceramic dielectric capacitor electrode. The tubular ceramic dielectric capacitor electrode is manufactured by adopting a specific process flow, the obtained product completely meets the requirements of performance parameters such as voltage resistance, insulation resistance, capacitance, dielectric loss tangent, weldability and bonding force, the product quality is high, the service life is long, the production efficiency is improved as manual silver coating is not needed, and the production cost is saved; and the tubular ceramic dielectric capacitor electrode manufacturing method based on chemical nickel plating and tin electroplating is particularly suitable for manufacturing the C-shaped tubular ceramic capacitor electrode.

Description

technical field [0001] The invention relates to a manufacturing method of a tubular ceramic capacitor electrode whose material is titanate series ceramics, in particular to a manufacturing method of a tubular ceramic capacitor electrode based on electroless nickel plating and electrolytic tin plating. Background technique [0002] Porcelain capacitors are capacitors whose dielectric material is ceramic. According to different ceramic materials, they can be divided into low-frequency ceramic capacitors and high-frequency ceramic capacitors; classified according to their structure, they can be divided into disc capacitors, tubular capacitors, rectangular capacitors, For feedthrough capacitors, etc., the terminal electrodes are usually prepared by coating silver paste and then sintering. [0003] The electrodes of traditional tubular ceramic capacitors are mostly made by hand-coating with silver (or palladium-silver) and then firing infiltration. In order to meet the product pe...

AI Technical Summary

Problems solved by technology

This process has the following defects: a large amount of precious metal silver or palladium is needed, and the process time required to prepare a batch of products is long; the capacity of the same product is closely related to the area coated, so due to human factors, the capacity of the product after coating Uniformity varies greatly; in addition, for short and small porcelain tubes, the coating operation is more difficult

[0005] At present, for alumina series ceramics, the electrodes are made of nickel plating using the process of "roughening-sensitization-activation-electroless nickel plating-heat treatment", but for barium titanate series of tubular ceramic capacitors, it is difficult Using this process to make electrodes, because the solderability of the nickel layer is poorer than that of tin, and the storage time is not long enough, it is necessary to electroplate tin on the nickel layer to meet the requirements of product solderability and long-term storage. However, the above process After nickel plating, heat treatment is required to improve the bonding force between the nickel coating and the ceramic, and the oxide layer on the surface of the nickel coating after heat treatment seriously affects the tin plating.

[0006] In addition, there is also a process of "silver coating-electroless nickel plating-electrotin plating" to make tubular ceramic capacitor electrodes, but this process is also long and uneconomical.