Zinc-nickel alloys are commonly used as plating materials for corrosion protection applications, and their salt spray resistance is critical for many industrial uses. Especially in areas such as marine equipment and automotive brake calipers, the protective properties of zinc-nickel alloys have a direct impact on the service life and reliability of the equipment. So how can we improve the salt spray resistance of zinc-nickel alloy blue passivation processes?
In the electroless nickel plating process, the porosity of the plated layer has a crucial influence on the corrosion resistance of the plated parts. If the porosity is high, the corrosion resistance of the plated parts will be reduced, which in turn affects their service life.
In recent years, black zinc passivation has been widely used as a common electroplating process to improve the appearance and corrosion resistance of galvanized layers. However, some users have found that after using black zinc passivation solution, the film salt spray capability of electroplated products has instead decreased. This phenomenon has attracted widespread attention from relevant researchers and industry. In order to effectively solve this problem, we need to gain a deeper understanding of the reasons behind it, which can be explored in the following aspects.
In the trivalent chromium colored zinc passivation process, the quality of the plating solution plays a crucial role in the quality of the passivated film layer formed. Among other things, the high content of heterometallic impurities such as copper, divalent iron and zinc ions is one of the main reasons for fogging failures in the film layer.
Many customers prefer the color appearance of hexavalent chromium passivator, because after using trivalent chromium zinc passivator, the color appearance of the workpiece does not meet the requirements, or the workpiece coating has poor corrosion resistance and affects the performance of the workpiece.
In the field of metal processing and protection, blue and white zinc passivators are widely used to improve the corrosion resistance of galvanized layers. Among them, blue-white zinc passivation is favored for its good corrosion resistance and ease of operation. This article describes how to test the corrosion resistance of passivated layers with blue-white zinc passivator using a neutral salt spray test.
