1. Microscopic Cross-Section Method
By cutting and polishing a sample cross-section, the plating thickness is directly measured using a microscope (accuracy up to ±1μm), suitable for laboratory environments.
2. X-ray Fluorescence (XRF) Method
Non-destructive measurement, using X-rays to excite the plating elements and analyze the attenuation intensity. High accuracy (±0.1μm), requires calibration with standard samples.
3. Coulometric Dissolution Method
Electrolytically dissolves the plating layer, calculating the thickness based on the amount of electricity. Can measure multi-layer plating (such as copper/nickel/chromium systems), accuracy ±5%.
4. Magnetic Method/Eddy Current Method
Suitable for chrome plating on an iron substrate. Measures thickness through changes in magnetic flux or eddy currents. Portable but significantly affected by the substrate material.
5. Chemical Dissolution Method
Timed Droplet Method: Dissolves the plating layer with hydrochloric acid, recording the time to calculate the thickness (only for thin layers <1.2μm, error ±15%).
Dissolution and Weighing Method: Weighs the sample after chemical dissolution to calculate the thickness, requires avoiding substrate interference.
6. Profilometer Method
Forms a step by dissolving or masking the substrate, measuring the step height. Suitable for irregular surfaces.
Selection Recommendations
High accuracy requirements: Prioritize X-ray fluorescence method or microscopic cross-section method.
On-site rapid testing: Magnetic/eddy current thickness gauge.
Multi-layer plating: Coulometric dissolution method.
