When inspecting them, we can distinguish them by the following aspects:. Trivalent chromium and hexavalent chromium are two common types of chromium plating in the galvanizing process. Although they both have corrosion protection and decorative effects, during visual inspection we can distinguish between them by the following aspects
Author: Marisa
When inspecting them, we can distinguish them by the following aspects:.
Trivalent chromium and hexavalent chromium are two common types of chromium plating in the galvanizing process. Although they both have corrosion protection and decorative effects, during visual inspection we can distinguish between them by the following aspects
1. Color difference
Trivalent chromium coatings are usually a brighter blue-white or silver-white, with a uniform and softer color. On the other hand, hexavalent chromium plating often shows dark yellow or orange-yellow color, which is relatively bright and sometimes may have a certain metallic luster. Therefore, during visual inspection, by observing the color of the chromium plating layer, we can initially determine whether it is trivalent chromium or hexavalent chromium.
2. Gloss comparison
In addition to color, trivalent chromium and hexavalent chromium also differ in terms of gloss. Generally speaking, the trivalent chromium coating has a relatively low gloss, showing a matte effect, and the overall appearance is smooth but not harsh. On the other hand, hexavalent chromium plating has a relatively high gloss, sometimes even reaching a mirror effect, reflecting light strongly and with a certain sense of sparkle. Therefore, by comparing the gloss level, we can further distinguish between the two kinds of chromium plating layer.
3. Examination of corrosion resistance
Although trivalent chromium and hexavalent chromium have a certain degree of corrosion resistance, but their degree of corrosion resistance is not the same. Under the same environmental conditions, hexavalent chromium plating usually shows stronger corrosion resistance, and can better resist the erosion and destruction of the external environment. Although trivalent chromium plating also has a certain degree of corrosion resistance, but relatively speaking, it may be slightly inferior. Therefore, in the process of long-term use, by observing the corrosion of the chromium plating layer, we can also distinguish between trivalent chromium and hexavalent chromium.
In summary, through the color, gloss and corrosion resistance and other aspects of observation and comparison, we can effectively distinguish between valent chromium and hexavalent chromium plating in the galvanizing process. This is of great significance for ensuring product quality, selecting the appropriate chromium plating process, and carrying out subsequent maintenance and management.