Hardness of bodies - Analysis of other behaviors

In this article, we first look at the case of tests carried out on alloys where the flow stress depends on the strain rate, for example in hot hardness tests. We then review current knowledge of the results of tests carried out with very low forces and penetrations where size effects are apparent. We then describe the fracture phenomena induced by the indentation of semi-fragile materials, namely the ductile/fragile transition, and how these can be used to measure the toughness of these bodies. Finally, we analyze the case of anisotropic materials: single crystals and polycrystalline bodies with a crystallographic texture.

This article is part of a series on hardness testing:

• Body hardness and qualitative analysis ;

• Hardness of common metals. Rigid-plastic limit case ;

• Hardness of materials. Influence of elasticity ;

• Hardness of bodies. Analysis of other behaviors [M 4 157] ;

• Find out more .