Rockwell C Hardness Testing Indentions
Rockwell C Preload and Major-Load Indentions at 10X Note the deformation around the major-load indention.
taken by Jeff Thomas, November 1997, with a light microscope
Rockwell C Preload Indention at 100X taken by Jeff Thomas, November 1997, with a JEOL SEM
Rockwell C Major-Load Indention at 100X taken by Jeff Thomas, November 1997, with a JEOL SEM
Rockwell C Indention at 1000X Zoomed on lower edge of indention.
taken by Jeff Thomas, November 1997, with a JEOL SEM
Soft materials, such as copper and mild steel, show an encircling ridge, which can be seen above, and hard materials, such as manganese steel and some bronzes, develop a depression.
From The Testing and Inspection of Engineering Materials, 3rd Ed., by H.E. Davis, G.E. Troxell, and C.T. Wiskocil, McGraw-Hill, 1964, p. 193.