If you just look at stainless steels, there are many alloys with 6+ elements, example below (904L is also know as Rolesor, used for steel Rolex watches) SS 904

If you just look at stainless steels, there are many alloys with 6+ elements, example below (904L is also know as Rolesor, used for steel Rolex watches) SS 904L: Nickel, Chromium, Carbon, Copper, Molybdenum, Manganese, Silicon, Iron Tool steel alloys (used for machine tools, hand tools, knives, etc) have iron, carbon, tungsten, chromium, vanadium and molybdenum. Carbon steel is the most basic alloy steel, it consists of iron and carbon (and impurities).