Three reasons for Hydrogen Embrittlement in Workpiece Plating During the Use of Electroless Nickel Brightener
Author:Robby
In the process of using electroplating nickel brightener, the workpiece nickel plating layer will produce hydrogen embrittlement phenomenon, resulting in the workpiece in the process of using the plating layer will appear cracks or fracture phenomenon and affect the use. So how can the workpiece plating layer produce hydrogen embrittlement phenomenon?
According to the field experience and product plating nickel brightener characteristics of the analysis, there are mainly the following three points:
1、The content of secondary brightener in plating solution is too high.
In the production process, the secondary brightener needs to be used in conjunction with the primary brightener in order to obtain a bright coating, leveling and good ductility of the coating. When the secondary brightener in the plating solution is too much, although bright plating can be obtained, but the bright range of the plating layer is narrow, the tensile stress is high, and the brittleness of the plating layer is big.
2、Excessive current density.
The current density is too high, the nickel plating layer is easy to burn, and the stress of the plating layer is large, brittle. Therefore, the current density should be adjusted in production within the process.
3, high content of zinc, lead and other metal impurities in the plating solution. When the plating solution of zinc, lead and other metal impurities in the high content, the nickel plating layer of the internal stress increases significantly, and brittle, serious black streaks.
In the production process, metal impurities can be removed using electrolysis, i.e., using a corrugated board as the cathode under agitation and electrolyzing at a current density of 0.2~0.4A/dm2.
Therefore, in the production process of using electroplating nickel brightener, attention should be paid to these 3 points, to avoid the phenomenon of hydrogen embrittlement of the workpiece nickel plating layer, and to reduce the occurrence of failures.