1. Surface defects of the plating layer
Pinholes/Pitting: Tiny holes or granular protrusions appear on the surface of the plating layer, mostly due to surface contamination of the substrate, impurities in the plating solution, or abnormal current density.
Blistering/Peeling: Insufficient adhesion between the plating layer and the substrate, often due to incomplete pre-treatment (such as failure to remove oil stains) or excessive stress in the plating layer.
Burning: The plating layer is rough and blackened, caused by excessive current or high temperature.
2. Performance defects of the plating layer
Insufficient hardness: The hardness of the plating layer does not meet the standard (e.g., hard chrome requires ≥800HV), possibly due to abnormal plating solution composition or improper heat treatment.
Poor corrosion resistance: Rusting occurs after the salt spray test, related to high porosity or insufficient thickness of the plating layer.
3. Uniformity defects of the plating layer
Uneven plating/Color difference: Inconsistent gloss of the plating layer, due to uneven current distribution or insufficient stirring of the plating solution.
Uneven thickness: Local plating is too thin or missing, related to improper mounting method or poor anode conductivity.
4. Functional defects
High porosity: Affects sealing or anti-corrosion performance, requiring detection through the filter paper method or ferric chloride test.
Cracking: The plating layer is brittle, possibly due to excessive organic impurities in the nickel layer or excessive thickness of the chromium layer.
