FCD-4MCu is an Fe-Cr-Ni-Cu-Mo alloy with a duplex structure of ferrite and austenite. Moderately high strength
and hardness are combined with good ductility and impact properties,.resulting in an alloy with superior
resistance to abrasion or erosion-corrosion. In chloride bearing environments the alloy is highly resistant to
stress-corrosion cracking. Resistance to nitric and sulphuric acids is high. Castings are most commonly used in
the solution annealed condition.