pure iron cannot be used since highly pure iron has low strength of 150 mega pascals.steel can be used in car bodies (plain steel is an alloy of iron and carbon). Steel with low Carbon content (ex: mild steel) is used and alloy steels can also be used. it has to be ductile and high fracture toughness. Good tensile strength is needed. For the copper to be used as electrical wires it has to be 99.7% pure. After copper is drawn to thin wires, it looser conductivity so it has to annealed to get back conductivity.
