260 



Copper and Copper-base Alloys 



TABLE 3 



10 PER CENT ALUMINUM BRONZE" 



Copper, 88.83%; aluminum, 10.02%; iron, 0.77%; manganese, 0.31% 



Property 



Forgings 

 hot 



Tensile strength, p.s.i. (000 omitted) 



Apparent elastic limit, p.s.i. (000 omitted) 



Yield strength: 



0.5% extension, p.s.i. (000 omitted) 



0.2% offset, p.s.i. (000 omitted) 



0.1 % offset, p.s.i. (000 omitted) 



Elongation, % in 2 in 



Reduction of area, % 



Endurance limit, p.s.i. (000 omitted) 



Rockwell hardness F, Vie-in. ball, 60-kg. load 



Rockwell hardness B, He-hi. ball, 100-kg. load 



Brinell hardness, 10-mm. ball, 500-kg. load 



Modulus of elasticity, p.s.i 



Melting point, °F 



Coefficient of expansion, per °C. from 25-300°C 



Electrical conductivity, % I.A.C.S., 68°F 



Thermal conductivity, B.t.u. per sq. ft. per ft. per hr. per °F., ( 



Density, lb. per cu. in 



Forging range, °F 



Forging quality 



Type structure 



85-90 

 22^2 



3&-50 

 34-50 

 30-45 

 12-23 

 12-30 



105-102 

 80-90 

 130-157 

 17,500,000 

 1905 

 0.0000170 

 13 

 36 

 0.274 

 1400-1650 

 Excellent 

 Two phase, alpha-beta 



■* This alloy has excellent hot-forging properties. 



^ Refers to rod cold-drawn 5% from extruded condition (extrusion temp. 1350°F.): rod i 



■= Refers to rod annealed 1350°F. for 1 hr. with ready-to-finish grain size 0.035 mm. 



100 



90 



c 80 



Q.60 



-■ 50 

 o 

 o 

 £ 40 



30 



20 



Extr. 5 10 



Percent Reduction by Cold Working 



Chart 18. — The effect of cold drawing on the tensile strength and 

 apparent elastic limit of 10 per cent aluminum-bronze rod, previously 

 extruded (88.83 % copper, 10.02 % aluminum, 0.77 % iron, 0.31 % 

 manganese) (rod under 1 in. in diameter). 



§110 



^100 

 o 



1 90 

 oi 

 ^80 



^ 70 



"o 

 fo 60 



-^50 



M 

 V5 



c 40 

 ^ 30 



<D 20 



Ex+r. 5 10 



Percent Reduction b^ Cold Working 



Chart 19. — The effect of cold drawing on the Rockwell hardness, 

 percentage elongation in 2 in., and percentage reduction of area of 

 10 per cent aluminum-bronze rod, previously extruded (88.83 % copper, 

 10.02 % aluminum, 0.77 % iron, 0.31 % manganese) (rod under 1 in. in 

 diameter) . 



