3. Hardness testing
3.1 Historical interest
They are used to classify materials according to their resistance to deformation by penetration with a harder material.
The first hardness scale was established arbitrarily by Mohs in 1820, for use by mineralogists. It comprises a list of 10 minerals ranked in order of increasing hardness, from talc "1" to diamond "10" to quartz "7", each crossing out the previous one and being crossed out by the next.
This scale is of no interest to the metallurgist. The hardest steel (quenched high-speed steel) would rank at around 8.5, while extra-hard steel would rank at around 3.5.
The experimental difficulties are great, and the precision relatively low. The...
The Ultimate Scientific and Technical Reference
This article is included in
The building envelope
This offer includes:
Knowledge Base
Updated and enriched with articles validated by our scientific committees
Services
A set of exclusive tools to complement the resources
Practical Path
Operational and didactic, to guarantee the acquisition of transversal skills
Doc & Quiz
Interactive articles with quizzes, for constructive reading
Hardness testing
Resilience testing
Bibliography
Standards and norms
NF EN 1090, which defines the requirements for the manufacture, inspection and certification of steel and aluminum products used in construction.
NF EN ISO 6892-1, which describes the method for tensile tests on metals.
NF EN ISO 6506-1, which describes the Brinell hardness test method for metallic materials.
NF EN ISO 6507-1, which describes...
The Ultimate Scientific and Technical Reference
