Rosiwal scale Rosiwal scale The Rosiwal scale is a hardness scale, with its name given in memory of the Austrian geologist August Karl Rosiwal. The Rosiwal scale bases its measure on absolute values, unlike the Mohs scale whose values are relative values, its interest is relegated to the amateur or an approach that makes it useful in the research field ('in situ'). The Rosiwal method (also called Delesse and Rosiwal) is basically a method of petrographic analysis and led to the development of the stereograph. Measures in an absolute scale the hardness of minerals expressed as abrasion's resistance, measured at laboratory, starting
Brinell scale be shown as XXX HB YY"D". The XXX is the force to apply (in kgf) on a material of type YY (5 for aluminum alloys, 10 for copper alloys, 30 for steels). Thus a typical steel hardness could be written: 250 HB 30"D". It could be a maximum or a minimum. Brinell scale The Brinell scale characterizes the indentation hardness of materials through the scale of penetration of an indenter, loaded on a material test-piece. It is one of several definitions of hardness in materials science. Proposed by Swedish engineer Johan August Brinell in 1900, it was the first widely