All about stainless steel

What is the alloying element that makes steel "stainless"?

• Nickel (Ni)

• Molybdenum (Mo)

• Chromium (Cr)

• Nitrogen (N)

What minimum amount of chromium is required for steel to be stainless steel?

• 20.5%

• 10.5%

• 30%

• 8%

Which of the following isn't a classification of stainless steel?

• Austenitic

• Ferritic

• Precipitation Hardening

• Annealed

Duplex stainless steel is so named as it is equally comprised of two different steel phases. What are they?

• Ferrite and martensite

• Austenite and ferrite

• Austenite and martensite

These microstructures show the phases present. Which one is for a duplex stainless steel?

• A

• B

• C

• D

Which of the following types of stainless steels are not magnetic?

• Ferritic

• Austenitic

• Martensitic

• Duplex

Most cutlery is made from 18/8 stainless steel. What are the two main alloying elements at 18% and 8% that contribute to its classification?

• 18% Chromium; 8% Nickel

• 18% Nickel; 8% Chromium

• 18% Chromium; 8% Molybdenum

• 18% Nickel; 8% Molybdenum

Nickel (Ni) is added to stainless steel to stabilise the austenite phase. With that in mind, is 18/8 stainless steel magnetic?

• Yes

• No

When calculating the Pitting [corrosion] Resistance Equivalent Number (PREN) which stainless steel alloying element does NOT contribute?

• Nickel (Ni)

• Chromium (Cr)

• Molybdenum (Mo)

• Nitrogen (N)

Which of the following isn't an actual duplex stainless steel?

• Super duplex

• Hyper duplex

• Mega duplex

• Lean duplex