about 5 5 wt mg alloy 2 realizes higher strength than alloy 1 alloy 10 demonstrates the benefit of increasing manganese at similar levels of copper and magnesium alloy 10 contains similar levels of mg cu zn and optional additives and unavoidable impurities as alloy 9 except alloy 10 contains about 0 95 wt mn as opposed to about 0 75 wt mn alloy 10 realizes both increasing tensile yield strength about a 1 8 increase with 30 cold work and a 3 6 increase with 50 cold work and ultimate tensile strength about a 1 0 increase with 30 cold work and about a 4 5 increase with 50 cold work alloy 4 also illustrates the beneficial strengthening effect of manganese alloys 1 and 4 contain similar mg zn and optional additives and unavoidable impurities except alloy 1 contains about 0 75 wt mn and alloy 4 contains about 0 95 wt mn alloy 4 realizes a higher strength while achieving a similar ductility to alloy 1 indicating the higher levels of mn may be beneficial alloys 4 and 10 also demonstrate that increased cold work with increased levels of manganese facilitate increases in strength alloys 4 and 10 both achieve higher percentage increases in strength at 50 cold work relative to 30 cold work alloy 4 realizes about a 5 increase in tys over alloy 1 at 50 cold work but only about a 2 6 increase in tys over alloy 1 at 30 cold work similarly alloy 10 realizes about a 3 6 increase in tensile yield strength over alloy 9 at 50 cold work but only about a 1 8 increase in tensile yield strength over alloy 9 at 30 cold work in other words.