To interpret Vickers hardness test results, you must first understand what the numbers mean and how they relate to material properties. Here's a breakdown to help you:

Recognizing the Format

• Hardness Number: This is a numerical value that represents the hardness of the material. Higher numbers indicate greater hardness.
• HV: The Vickers hardness scale is indicated.
• Load (kgf): This is the test load that was used in the measurement. Micro-Vickers tests are typically 10gf to 1kgf, whereas macro-Vickers tests are 5kgf to 30kgf.

Using the Hardness Number to Interpret

• Relative comparison within the sample: A sample's hardness can be compared across different areas of the same sample or between samples subjected to similar conditions.
• Comparison with reference values: Check to see if your material type has established hardness ranges. This enables you to compare your sample to those of others.
• Consider the load: Higher loads may result in slightly lower hardness values due to material deformation. However, the values usually stabilize above 200gf.

Additional Factors

• Test conditions: Ensure that all equipment is properly prepared, tested, and calibrated.
• Reporting format: Additional information, such as indentation size or conversion to other hardness scales, may be included in some reports.
• Material microstructure: The grain size, phase presence, and phase distribution can all influence hardness.