• The gray iron class 40 alloy has moderate strength (40 ksi ultimate), but low ductility (<0.5%) that that will not meet the mechanical requirements of the coupler.
  
• The fatigue limit of the gray iron 40 alloy is 18 ksi and does not meet the performance requirements.
  
• The alloy has a nominal machining speed of 115 m/min with carbide tools which exceeds the machining requirement.
  
• The gray iron class 40 alloy does not meet all the performance requirements and should not be selected.

Go back to the alloy page and select an alternate cast iron alloy.