chrome steel 
noun [mass noun]
A hard fine-grained steel containing chromium, used for making tools.High quality fuel injectors are usually made of high alloy chrome steel that can withstand harsh conditions under the hood....
- The LCU contains the pump, radiator, reservoir and cooling fan, all neatly enclosed in an attractive looking brushed aluminium and chrome steel enclosure.
- Chrome steel was employed in the production of armor plate and projectiles because of its hardness and resistance to shock.