Troubleshooting abnormal problems

1. If the surface of the workpiece is too rough, difficulties may be encountered when evaluating the corners of the indentation, especially when using automated equipment.
When using automated hardness testing, scratches from the preparation process may lead to incorrect readings of the indentation size.
Solution:
Use a polished surface.
Surface preparation requirements depend on the load applied to the material and the hardness of the material: the softer the material, the higher the quality of polishing required.

2. For specimens with a high degree of etching, it may be difficult to evaluate the corners of the indentation, which may lead to incorrect hardness test results.
Solution:
Etching should be avoided as much as possible because it leads to a reduction in the reflective surface. If etching must be performed, light etching is preferred so that the corners of the indentation can be distinguished.
For example, etching is occasionally required when evaluating welding points.

3. Hardness values are higher than expected.
Solution:
Check relevant regulations to ensure that the correct indentation spacing was used in the hardness test.
If the hardness indentations are too close to each other, strain hardening may occur.