The alloying element of 2017 is copper, which is based on the previous 2nd-ranked alloy for industrial application. It has high strength and good cutting performance, but has poor corrosion resistance. Mainly used in rivets, general mechanical parts, aircraft, ships, traffic, building structure parts, transportation tool structure parts, propeller components and accessories. Chemical Composition Limits wt% Cu Si Fe Mn Mg Zn Cr Ti Pb.Bi Al 3.5-4.5 0.2-0.8 0.70 0.4-1.0 0.4-0.8 0.25 0.10 0.15 / margin Typical Alloy 2017-T451 Mechanical and Physical Properties (Typical Mechanical & Physical Properties) Weldability Machinability Corrosion resistance Conductivity 20°C (68?) (%IACS) density (20°C)(g/cm3) better well difference 30-40 2.79 tensile strength (25°C MPa) Yield strength (25°C MPa) hardness 500kg force 10mm ball Elongation rate 1.6mm (1/16in) thickness Large shear stress MPa 425 275 105 20 260