alclad technicality under the ford airplane company section alclad is stated to be a new alloy that combined the corrosion resistance of aluminum with the strength of duralumin this is incorrect aluminum is an element and duralumin is an alloy itself of aluminum you can't characterize an alloy as being made of an element and another alloy in addition to that alclad is actually not an alloy but a sheet of aluminum composite as described here here and here as a side note perhaps one could make a stub for alclad based on the technical definition provided by someone who manufactures it