When iron is alloyed with nickel and chromium, it forms stainless steel, a corrosion-resistant alloy widely used in various industries. Nickel enhances the toughness and ductility of the steel, while chromium contributes to its corrosion resistance by forming a passive oxide layer on the surface. This oxide layer prevents further oxidation, making stainless steel highly resistant to rust and corrosion in various environments. The resulting alloy exhibits excellent mechanical properties, high strength, and resistance to heat and chemical damage, making it suitable for applications in construction, automotive, aerospace, and many other fields.