The Brasses 



70 



60 



37 



400 500 600 700 800 900 1000 1100 1200 1300 1400 

 Annealing Temp. in Deg.E ( 1 Hr. a+ Temp.) 



Chart 22. — The efifect of annealing on the yield strength of com- 

 mercial bronze (Government-gilding) strip, previously cold-rolled 

 6 B. & S. Nos. (50 per cent reduction of area) from a grain size of 0.015 

 mm. (89.74% copper) (0.040-in. stock). 



50 



(/Q 40 



o 30 



20 



400 500 600 700 800 900 1000 liOO 1200 1300 1400 

 Annealing Temp. in Deg.H(lHnat Temp.) 



Chart 23. — The effect of annealing on the yield strength of com- 

 mercial bronze (Government-gilding) strip, previously cold-roUed 6 

 B. & S. Nos. (50 per cent reduction of area) from a grain size of 0.070 

 mm. (89.74 % copper) (0.040-in. stock). 



80 



70 



,?60 



40 50 60 70 80 90 100 110 



Rockwell Hardness F- '/is" Ball 60 Kg. Load 



5 23 40 58 76 



Rockwell Hardness 5-/16" Ball lOOKg. Load 



63 68 -74 80 85 



Rockwell Hardness I5-T- /i6" Ball 15 Kg. Load 



19 31 43 55 67 



Rockwell Hardness SO-T-Hs" Ball 30 Kg. Load 



Chart 24. — This chart can be employed to determine the approxi- 

 mate tensile strength and percentage elongation of commercial bronze 

 (Government-gilding strip (89.74 % copper) when only Rockwell 

 hardness is known. It is accurate for all thicknesses between 0.020 

 and 0.080 in. within the given limits. 



70 



60 



50 



40 - 



o 30 



20 



aooi 



0002 O003 Q004 

 strain- Inches per In. 



O005 O.006 



Chart 25. — The effect of cold working on the stress-strain charac- 

 teristics of commercial bronze (Government-gilding) strip (0.040 in. 

 thick) having a ready-to-finish grain size of 0.015 mm.; 5,000-lb. 

 capacity hydraulic testing machine and Templin automatic exten- 

 someter accurate to 0.00001 in. used (89.74 % copper). 



