Duplex steel is made up of:: (A) Martensitic steel and austenitic steel, (B) Ferritic grain of stainless steel, (C) Ferritic + austenitic grains of stainless steel, (D) Ferritic + martensitic grains of stainless steel
Answer is C. Duplex stainless steel is a combination of both ferritic and austenitic grains of stainless steel. The basic chemical composition of duplex stainless steel is an equal mix of ferrite and austenite. This combination creates some very beneficial properties for this family of stainless steels.