Palmqvist method


The Palmqvist method, or the Palmqvist toughness test, is a common method to determine the fracture toughness for cemented carbides. In this case, the materials fracture toughness is represented by the critical stress intensity factor KIc.

Approach

The Palmqvist-method uses the lengths of the cracks from a number of Vickers indentions to determine the fracture toughness. The Palmqvist fracture toughness is given by:
Where HV is the Vickers hardness in N/mm2 with P indentation load and T is the total crack length from the indenter.