Physical Properties Group C (Class 20, 21, 22)

Group C Specialty Materials Alloy Number Rockwell Hardness Electrical Conductivity      Yield Strength        Ultimate Tensile Strength Elongation %
     
%IACS [Ms/m] 0.2% Offset Ksi [Mpa]
     
  Ksi [Mpa]  
Minimum Minimum Typical Typical IN 2" or 4 X D
Class 20 C15760 75 HRB 75% [43.5] 60 [413] 74 [510] 25
Class 21 C15715 62 HRB 92% [53] 48 [331] 58 [400] 30
Class 22 C15725 68 HRB 87% [50] 54 [332] 65 [448] 27

Notes:

Acceptance is based on hardness and conductivity only. 

Reference:

American Welding Society Publication J1.3