Question: which one of the following elements is the most important alloying ingredient in steel?
Answer: Chromium is one of the most popular alloying metals for steel due to its high hardness and corrosion resistance. On its own, chromium is a grey, hard and brittle metal with a high temperature resistance and a melting point of 1907°C (3465°F). In steel, chromium alloyed to increase hardenability.