What is the Rockwell Hardness for D2 tool steel?

D-2 is a tool steel that is supplied in the annealed or soft condition. This grade must be hardened after machining . D-2 is heat treated between 1825 to 1875F. After heat treating, the tool steel will attain a hardness of about RC 62-64. However, after hea treating, the steel is very brittle and must be tempered. Below is a list of common temperatures for D2 try this......Tempering °C

150

200

250

300

350

400

HRc

62/61

61/60

60/59

57/56

56/55

56/55

See the related links for the D-2 tool steel data sheet and an introduction to the heat treating process.