Vickers Hardness Test Formula |
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\( HV \;=\; 1.854 \cdot \dfrac{ F_a }{ d^2 } \) (Vickers Hardness Test) \( F \;=\; \dfrac{ HV \cdot d^2 }{ 1.854 }\) \( d \;=\; \sqrt{ \dfrac{ 1.854 \cdot F }{ HV } }\) |
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| Symbol | English | Metric |
| \( HV \) = Vickers Hardness Test | - | \( kgf\;/\;mm^2 \) |
| \( F_a \) = Applied Force | - | \( kgf \) |
| \( d^2 \) = Area of Identification | - | \( mm^2 \) |
Vickers hardness test, abbreviated as HV, is a method for measuring the hardness of materials. The Vickers hardness test is known for its accuracy and versatility, making it one of the most popular hardness testing methods in materials science and engineering.
In the Vickers hardness test, a small, precisely shaped diamond indenter with a square-based pyramid shape is pressed into the surface of the material being tested with a known force. The test force is typically applied using a hydraulic or pneumatic system. The indenter is held in place for a specified duration, usually a few seconds, to create an indentation in the material.
The Vickers hardness test is used to assess the hardness of a wide range of materials, including metals, ceramics, and some polymers. It is particularly well suited for materials with high hardness values, as it provides precise and consistent results. The Vickers test can be performed on small or thin samples and can be used for quality control and material characterization in various industries, such as manufacturing, aerospace, and metallurgy.
Vickers Hardness Number Interpretation
- Low Vickers Hardness Number (HV < 100) - Soft materials like copper, brass, or polymers. Easier to machine but less wear-resistant.
- Moderate Vickers Hardness Number (HV = 100-400) - Common for metals like mild steel or aluminum alloys. Balances hardness and ductility.
- High Vickers Hardness Number (HV > 400) - Indicates very hard materials like hardened steels, ceramics, or tool coatings. Suitable for high-wear applications but may be brittle.
Factors Affecting Interpretation
Material Type - Compare HV against reference tables for the material class (e.g., steel, aluminum).Test Conditions - Ensure consistent load (typically 1–100 kgf) and dwell time (10–15 seconds). Low loads (<1 kgf) are for microhardness testing.
Surface Preparation - Surface roughness or coatings can skew results.
Application Context - Correlate HV with requirements like wear resistance or fatigue strength.
