Hardness Testing

Portable hardness testers are designed to measure the hardness of materials on-site or in environments where traditional, stationary hardness testing equipment cannot be used. These testers are compact, easy to use, and provide quick, reliable results, making them ideal for field inspections, quality control, and maintenance applications.

Here’s a detailed look at the types of portable hardness testers and their applications:

1. Rebound (Leeb) Hardness Testers

  • Method:
    • Uses the Leeb rebound principle, where a test tip (usually a tungsten carbide ball) is propelled against the material’s surface.
    • The hardness value is determined by measuring the rebound velocity of the tip compared to its impact velocity.
    • The result is typically displayed in Leeb hardness units (HL) and can be converted to other hardness scales like Rockwell, Brinell, and Vickers.
  • Applications:
    • Suitable for large and heavy workpieces like castings and forgings.
    • Ideal for on-site testing of installed machinery, welds, and heat-affected zones.

2. Ultrasonic Contact Impedance (UCI) Hardness Testers

  • Method:
    • Uses a vibrating rod with a Vickers diamond indenter at the tip.
    • The hardness is determined by measuring the frequency shift of the vibrating rod as the indenter penetrates the material.
    • The result is displayed in Vickers hardness (HV) and can be converted to other scales.
  • Applications:
    • Suitable for thin-walled or small parts, coatings, and welds.
    • Used in various industries, including aerospace, automotive, and precision manufacturing.

3. Portable Rockwell Hardness Testers

  • Method:
    • Similar to stationary Rockwell testers but designed for portability.
    • Uses a diamond cone or steel ball indenter and measures the depth of penetration under a minor and major load.
    • The result is displayed directly in Rockwell hardness units (e.g., HRA, HRB, HRC).
  • Applications:
    • Ideal for testing hardness in the field or on large parts that cannot be easily transported.
    • Commonly used in construction, metalworking, and maintenance industries.

4. Portable Brinell Hardness Testers

  • Method:
    • Designed to replicate the Brinell hardness test method in a portable format.
    • Uses a steel or carbide ball indenter and applies a known load to the material.
    • The diameter of the indentation is measured, and the Brinell hardness number (BHN) is calculated.
  • Applications:
    • Suitable for testing large and heavy workpieces, such as steel plates and castings.
    • Used in industrial environments where stationary Brinell testers are impractical.

5. Pencil Hardness Testers

  • Method:
    • Uses standardized pencils with varying hardness grades to scratch the surface of a material.
    • The hardness is determined by the hardest pencil that does not scratch the surface.
  • Applications:
    • Commonly used for testing coatings and films.
    • Ideal for on-site inspections of paint, varnish, and other surface coatings.