The Aluminum Bronzes 



257 



CD 500 600 700 800 900 1000 1100 1200 1300 1400 

 Annealing Temp, in Deg.Ff l-Hr.at Temp.) 



Chart 9. — The effect of annealing on the Rockwell hardness, 

 percentage elongation in 2 in., and grain size of 5 per cent aluminum- 

 bronze condenser tube, previously cold-drawn 20 per cent (reduction 

 of area) (94.62 % copper, 4.69 % aluminum). 



100 200 300 400 500 600 700 800 900 . 1000 

 Temperature in Deg.Ff 1 Hi: at Temp.) 



Chart 10. — Effect of elevated temperature on the tensile strength 

 and percentage elongation in 2 in. of 5 per cent aluminum-bronze tube 

 (94.62 % copper, 4.69 % aluminum). 



TABLE 2 

 8 PER CENT ALUMINUM BRONZE" 



Copper, 91.73%; aluminum, 8.01%; lead, trace; iron, trace; nickel, nil 



Property 



Rod 



Hard!" Soft 



Forgings 



Hot Cold'* Cold' 



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, Jfg-in. ball, 60-kg. load 



Rockwell hardness B, He-in. 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 25-3(X)°C 



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



Thermal conductivity, B.t.u. per sq. ft. per ft. per hr. per °F., 68°F 



Density, lb. per cu. in 



Forging range, "F 



Forging quality 



Type structure 



140 

 100 



67 

 10 

 40 

 22 

 108 



60 

 15 



15 

 15 



15 

 70 

 75 



74 

 33 



60-70 

 15-20 



15-40 

 15-40 

 15-40 

 60-70 

 70-75 

 22-23 

 74-84 

 33-48 

 69-81 

 17,500,000 



1905 



0.0000178 



14.8 



46 



0.281 



1400-1600 



Excellent 



Single phase, alpha 



70-80 

 20-40 



50-40 

 65-60 



95-100 



67-76 



106-122 



85 

 50 



30 

 50 



104 



•• This alloy has excellent hot-working properties and can be cold-worked; compares i 



t* Refers to rod cold-drawn 50 %, rod under 1 in. in diameter, ready-to- finish grain si; 



" Refers to 1300°F. anneal (1 hr.). 



^ Material cold-forged from soft rod (5-10% reduction of area). 



• Material cold-forged from cold-worked condition (10%). 



L this respect with Type A silicon bronze. 

 ! 0.070 mm. 



