The Tin Bronzes 



271 



60 



TO eo 90 100 



Rockwell Hardness B yi6"Ball 100 Kq. Load 

 91 97 - - 



Rockwell Hardness F '/le" Ball 60 Kg. Load 

 80 84 87 90 93 



Rockwell Hardness 15 T l^i6"Ball 15 Kq. Load 

 57 64 70 76 82 



Rockwell Hardness 30 T /i6"Ball 30 Kq. Load 

 Chart 15. — This chart can be employed to determine the approximate tensile strength and percentage elongation of 8 per cent phosphor- 

 bronze strip (7.5 % tin, 0.056 % phosphorus, balance copper) when only Rockwell hardness is known. It is accurate for all thicknesses between 

 0.020 and 0.080 in. within the given limits. 



TABLE 3 

 CAROBRONZE 



General Data — Tube 

 Analysis (approximate) : copper, 91.70%; tin, 8.00%; phosphorus, 0.30% 



Property 



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) 



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



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



Elongation, % in 2 in 



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



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



Young's modulus of elasticity" p.s.i 



Melting point, "F 



Density, lb. per cu. in 



Coefficient of expansion,"* 



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



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



Hard- 



77-95 

 46-62 



34-15 



107-114 



86-99 



16,000,000 



Soff- 



59 



20 

 22-23 

 22-23 

 22-23 



63 



77 



38 

 19,000,000 



1877 



0.318 



0.0000182 



13.00 



36 



■ ?s in. O.D. X 0.050 in. wall thickness. Ready-to-finish grain, 0.035 mm. 15-30 % reduction in are 



' 1200°F. anneal (1 hr. at temperature) of material described in footnote a. 



' Secant modulus to the apparent elastic limit. 



' Average linear coeffityent per °C. from 25-300°C. 



= Tests made in the laboratory of the Skodawerke in Pilsen, on material of medium tensile strength. 



by cold drawing. 



