The Webster Hardness Tester, also known as the Webster Hardness Gauge or Webster Hardness Tester/Barber Colman Type Hardness Tester, is a handheld instrument used to measure the hardness of soft metals, specifically aluminum and copper alloys. It provides a quick and non-destructive method for assessing the relative hardness of these materials.
The Webster Hardness Tester operates based on the rebound principle. The instrument features a spring-loaded impact body with a spherical indenter made of hardened steel or tungsten carbide. The indenter is pressed against the material surface with a specific force, and the hardness value is determined based on the rebound or spring-back of the impact body.
Here’s how the Webster Hardness Tester typically works:
- Calibration: Before use, the instrument is calibrated using a standard test block with a known hardness value. This calibration ensures accurate and consistent measurements.
- Testing: The Webster Hardness Tester is placed perpendicular to the material surface, and the impact body with the indenter is pressed against the surface. The impact body is released, and it rebounds or springs back from the material surface.
- Reading: The hardness value is determined by reading the position of the rebound indicator on the instrument. This position corresponds to a hardness value on the scale of the instrument.
The hardness values obtained from the Webster Hardness Tester are specific to the instrument and cannot be directly correlated with other hardness scales, such as Rockwell or Brinell hardness. The measurements are relative and used primarily for comparative purposes or for assessing the consistency of hardness within a specific material.
The Webster Hardness Tester is commonly used in industries such as metal fabrication, foundries, and quality control for assessing the hardness of soft metals during production or on-site inspections. It is a portable and easy-to-use instrument that provides a quick indication of material hardness without the need for complex sample preparation or destructive testing methods.
