72 



Copper and Copper-base Alloys 



10 



60 



50 



40 



50 



20 



40O 500 600 700 800 900 1000 1100 1200 1300 1400 

 Annealing Temp. in Deg.HflHr. a+ Temp.) 



Ch.\rt 135. — The effect of annealing on the yield strength of common 

 high-brass strip, previously cold-rolled 6 B. & S. Nos. (50 per cent 

 reduction of area) from a grain size of 0.070 mm. (66.49 % copper) 

 (0.040-in. stock). 



50 60 70 80 90 100 110 



Rockwell Hardness F- /is Ball eOKg.Load 



5 23 40 58 76 



Pockweil Hardness B->i6"BaIl 100 Kg. Load 



63 68 74 80 85 



Pockweil Hardness l5T-'/i6Ball 15 Kg. Load 



19 31 43 55 67 



Pockweil Hardness 30T-'/i6" Ball 30Kg.Load 



Chart 136. — This chart can be employed to determine the approxi- 

 mate tensile strength and percentage elongation of common high-brass 

 strip (66.49 % copper) when only Rockwell hardness is known. It is 

 accurate for all thicknesses oetween 0.020 and 0.080 in. within the 

 given limits. 



0001 



0.002 0.003 0004 Q005 

 S+rai'n, Inches per In. 



0.006 



Chart 137. — The effect of cold rolling on the stress-strain charac- 

 teristics of common high-brass strip (0.040 in. thick) having a ready- 

 to-finish grain size of 0.015 mm. (66.49 % copper); 5,000-lb. capacity 

 hydraulic testing machine and Teraplin automatic extensometer 

 accurate to 0.00001 in. used. 



OOOl 



0.002 0.003 0004 0.005 

 Strain, Inches per In. 



0.006 



Chart 138. — The effect of cold rolling on the stress-strain charac- 

 teristics of common high-brass strip (0.040 in. thick) having a ready- 

 to-finish grain size of 0.070 mm. (66.49 % copper); 5,000-lb. capacity 

 hydraulic testing machine and Templin automatic extensometer 

 accurate to 0.00001 in. used. 



