Vickers Hardness Tester

A Vickers hardness tester is a device used to measure the hardness of materials based on the Vickers hardness test method. The Vickers hardness test is a widely used method for determining the hardness of metals, alloys, and other solid materials. It involves indenting the material with a diamond or hard steel indenter and measuring the size of the resulting indentation.

Here are some key features and aspects of Vickers hardness testers:

1. Principle: The Vickers hardness test is based on the principle of measuring the diagonal lengths of the indentation left by the indenter. The test measures the resistance of a material to plastic deformation caused by a controlled applied load.

2. Indenter: The Vickers hardness test typically uses a pyramidal diamond or steel indenter. The indenter has a square-based pyramid shape with a precise angle between opposite faces, usually 136 degrees. The indenter is pressed into the material under a specific load.

3. Test Procedure: In the Vickers hardness test, the indenter is pressed into the material using a predetermined load, and the indentation is held for a specified duration. After removing the load, the indentation's diagonals are measured using an optical microscope or an automated measurement system.

4. Calculation of Hardness: The Vickers hardness number (HV) is calculated by dividing the applied load by the surface area of the indentation. The HV value represents the hardness of the material and is expressed in units of kilogram-force per square millimeter or gigapascals.

5. Wide Applicability: Vickers hardness testing is suitable for a wide range of materials, including metals, ceramics, composites, and some plastics. It is commonly used in quality control, material research, and engineering applications.

6. Microhardness Testing: Vickers hardness testers can also be equipped with a microscope for microhardness testing. Microhardness testing involves using lower test loads and measuring smaller indentations, allowing for hardness evaluation of smaller or more delicate materials or specific microstructural regions.

7. Automatic Testers: Vickers hardness testers are available in manual and automatic configurations. Automatic testers have motorized stages, automated indentation and measurement systems, and computerized controls, offering higher efficiency and accuracy in testing.

8. Standards and Calibration: Vickers hardness testers should conform to relevant international standards, such as ISO 6507 and ASTM E92. Regular calibration and maintenance of the equipment are necessary to ensure accurate and reliable hardness measurements.

Vickers hardness testers are widely used in industries such as manufacturing, metallurgy, aerospace, automotive, and research laboratories to assess material hardness and evaluate material properties for quality control, material selection, and process optimization.