Compare and convert between different hardness testing methods
Indenter: 10mm Tungsten Carbide Ball
Measurement: Diameter of indentation
Load: 3000 kgf
Best for: Castings, forgings, large parts
Indenter: 120° Diamond Cone
Measurement: Depth of indentation
Load: 150 kgf
Best for: Hardened steels, tools, gears
Indenter: 1/16" Steel Ball
Measurement: Depth of indentation
Load: 100 kgf
Best for: Soft steels, aluminum, brass
Indenter: 120° Diamond Cone
Measurement: Depth of indentation
Load: 60 kgf
Best for: Thin steel sheets, carbides
Indenter: Square Diamond Pyramid
Measurement: Diagonal lengths
Load: 1-120 kgf
Best for: High precision, thin layers, research
Indenter: Elongated Diamond
Measurement: Long diagonal length
Load: < 1 kgf
Best for: Thin coatings, brittle ceramics
The Leeb method is a dynamic "rebound" test that measures the velocity ratio of an impact body before and after hitting the surface.
It's portable and ideal for testing massive structures like bridge beams, large pipes, or installed machinery that cannot be moved to a lab.
Approximate conversion values between different hardness scales. Note: These are guidelines and may vary based on material composition.
| HRC | HRA | HRB | HBW | HV | HK | HLD |
|---|
The Switchover: HRC and HRB overlap around HRC 20. Generally, don't use HRC for materials softer than 20, and don't use HRB for materials harder than 100.
HBW vs HV: At lower hardness levels (below 300), Brinell and Vickers numbers are very similar. As material gets harder, values diverge.
Precision: Vickers is the only scale that is technically "continuous" from very soft to very hard. Brinell is restricted to softer/medium range.
Material Dependency: Conversion values are approximate and can vary based on material composition, heat treatment, and microstructure.
Brinell (HB)
Best for rough surfaces and large grain structures
Rockwell (HR)
Fast, direct reading, ideal for quality control
Vickers (HV)
Universal method, high precision for research
Knoop (HK)
Microhardness for thin coatings and brittle materials
Leeb (HLD)
Portable rebound test for on-site measurements