To make the steel hard requires increase in –

Which of the following elements are included in stainless steel?

How much carbon does steel contain?

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

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

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