Steels containing high percentages of certain alloying elements such as manganese and nickel which are austenitic at room temperature and cannot be hardened by normal heat-treatment but do work harden. They are also non-magnetic. Typical examples of austenitic steels include the 18/8 stainless steels and 14% manganese steel.

Nohara Formula is used to calculate the temperature Md30 at which an amount of 50 % austenite will be transformed to martensite through cold-deformation of 0.30 true strain. Nohara Formula can be given as:

M_d30=551 - 462 * %C - 9.2 * %Si - 8.1 * %Mn - 13.7 * %Cr - 29 * %Ni - 18.5 * %Mo - 29 * %Cu - 68 * %Nb - 462 * %N - 1.42 * (GS[ASTM] -8.0)

The standard value assigned to austenitic stainless steel to denote a specific ferrite content; used instead of percent ferrite. The formula for Avesta Ferrite Number FNA assumes parallel lines of constant ferrite numbers. FNA Cr-equivalence includes Ti as an additional element. FNA Ni-equivalence contains Cu and Co as additional elements. formulas for FNA can be given as:

C_req = Cr + 1.5 Si + Mo + 2 Ti + 0.5 Nb
N_ieq = Ni + 30 (C + N) + 0.5 Mn + 0.5 Cu + 0.5 Co
FNA = 3.34 Creq - 2.46 Nieq - 28.6