AK Steel 434 is a modification of Type 430, one of the most widely used of the "non-hardenable" ferritic stainless steels. The addition of molybdenum increases this alloy's corrosion resistance and its attack from many deicing chemicals. It also provides good heat and oxidation resistance up to 1500°F (816°C) as well as good mechanical properties.

Typical consumer product applications include automotive trim and molding, furnace combustion chambers, dishwashers, range hoods, gas burners on heating units, gutters and down spouts, steam iron bases and flatware. Commercial and industrial applications range from interior architectural uses to nitric acid plant equipment, oil refinery equipment, roofing and siding and restaurant equipment.