Which one of the following metal is NOT an essential component in stainless steel?

Which of the following elements are included in stainless steel?

Which one of the following alloys contains a non-metal as one of its constituent?

Alloy of which metal is used to make aeroplane and parts of the compartment of the train?

Which among the following are constituents of brass?

Which of the following elements is added to iron to produce steel which can resist high temperature, have high hardness and abrasion resistance?