• The 100-70-03 ductile iron is a high strength alloy (100 ksi ultimate and 70 ksi yield) that can easily meet the mechanical requirements of the coupler. The ductility is limited to 3%.

• The fatigue limit of the 100-70-03 alloy is 40 ksi and does meet the performance requirements.

• The alloy has a nominal machining speed of 66 m/min with carbide tools.

• Overall, the 100-70-03 alloy is the best alloy selection.

The 100-70-03 ductile iron alloy is the best alloy choice.           
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