HV ≈ 0,1891 F / d²F: N; d: average of the diagonals in mm.
Use when: Vickers conventional expression; if F is in kgf, the coefficient is approximately 1.8544.
Material hardness testing
Distinguish between indentation, scratch and rebound tests.
What is happening?
Hardness describes resistance to local action according to a defined method. Brinell, Vickers and Rockwell use indentation, Mohs compares scratch, and some Shore methods rely on other mechanical responses.
Values from different scales are not directly interchangeable. Load, indenter, surface preparation and sample thickness are part of the test result.
The formulas, with their conditions.
p = F / Ap: pressure; F: strength; A: contact area.
Use when: Physical idea of charge related to the surface; does not replace the standardized definitions of each scale.
Where is this principle used?
Heat treatment workshop
Check the effect of quenching or tempering.
Foundry and mechanical manufacturing
Check parts and compare materials.
What to observe in the experiment
At the same Vickers load, compare two impressions: connect the diagonal to the hardness and check the unit of force.
References and readings
This sheet explains the principles and their assumptions. Educational simulation can simplify the process; an industrial model requires suitable data and validation.
Have you understood the essentials?
Only one correct answer per question. Answer all three questions, then view the answer key.
Intu Lab · Understanding sheet · Kimba Christian