This paper mainly briefly introduces the structural features and working principle of the Leeb hardness tester:
2.1 Structural features
2.2 Working principle
Its basic principle is that an impact body with a certain mass impacts the surface of the sample under a certain test force, and measures the impact velocity and rebound velocity at a distance of 1mm from the impact body to the sample surface. Using the electromagnetic principle, the induction is proportional to the speed. voltage. The Leeb hardness value is expressed by the ratio of the rebound velocity of the impact body to the impact velocity. Harder materials produce faster rebound than softer ones.
Calculation formula:
The hardness value measured by the Leeb hardness tester is represented by HL, and the Leeb hardness value can be converted into other hardness units (including Rockwell B and Rockwell C, Vickers, Brinell and Shore D). When measuring the hardness of a material with the traditional static hardness test method, the change of the applied pressure will directly lead to the change of the hardness value. Similarly, in the Leeb hardness measurement, when you change the impact device, the hardness value will also change. Different impact devices are used to test the hardness of the same test block, and the Leeb hardness value will be different. Right now:
2.4 Material code
This article is mainly excerpted from " Leeb Hardness Tester Instruction Manual "