Here are the workpieces sent by the customer for coating hardness testing.
Since the coating thickness is usually very thin and measured in micrometers, it is difficult to obtain accurate hardness values by conventional methods. Therefore, the micro Vickers hardness test method is commonly adopted for coating hardness measurement, generally denoted by HV.
As the coating layer is extremely thin, direct hardness measurement on the coating is challenging. The substrate material or underlayer will interfere with the hardness test results. Before testing, we prepare the workpieces into standard specimens and then conduct the hardness inspection.
I. Specimen Preparation Process
Sampling:The coating specimen is cut by a metallographic mounting press to ensure the cross-section completely contains the coating layer and substrate base material.
Mounting: Use a metallographic mounting press to mount the specimen to prevent edge collapse and coating peeling.
Grinding and Polishing:Grind the specimen step by step from coarse sandpaper to fine sandpaper, then polish it with a metallographic grinding polishing machine until the cross-section is scratch-free, the boundary between the coating and the substrate is clear, and no deformed layer remains.
II.Hardness Testing Procedure
We adopt the below Vickers hardness tester equipped with an automatic measurement system for testing.
Place the prepared specimen steadily on the worktable of the hardness tester with the coating cross-section facing upward. Gently fix the specimen with a pressing block to ensure it is free from shaking and tilting.
III.Testing Procedure
Manual Focus (Optional for Auto-Focus Model)
Manually adjust the focus of the instrument to clearly display the surface texture of the workpiece on the computer interface.
Start Measurement
Set the measurement path on the computer and click Start to begin the test process.
Automatic Indentation Loading
The instrument automatically applies the set test force → dwell holding → unloading, and forms a diamond-shaped Vickers indentation.
Automatic Indentation Measurement
The lens automatically identifies the diagonal length of the indentation, and the system automatically calculates the Vickers hardness HV value.
Coating Thickness Calculation
Determine the interface position between the coating and the substrate, and the software automatically calculates.
If you are interested in these sample preparation equipments and micro Vickers hardness test, pls see products list and feel free to contact us to learn more about them.
MP-2000 metallographic gringding and polishing machine:
HVT-1000A micro Vickers hardness tester:
Post time: May-15-2026
