106 



Copper and Copper-base Alloys 



400 500 600 700 800 900 1000 1100 1200 1300 

 Annealing Temp. in Deg.F (I Hr. a+ Temp.) 

 Chart 49. — The effect of annealing on the yield strength of leaded- 

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

 of area) from a grain size of 0.080 mm. (63.35 % copper, 2.79 % lead, 

 balance zinc) (0.040-in. stock). 



100 



90 



80 



70 



60 



Co 

 !" -• 50 



10 20 30 40 50 60 70 80 90 

 Rockwell Hardness B" Vie" Ball 100 Kg. Load 



63 69 74 80 86 91 97 

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



64 67 71 74 77 80 84 87 90 

 Rockwell Hardness 15-T '/i6"Ball 15 Kg. Load 



22 29 36 43 50 57 64 70 76 

 Rockwell Hardness 30-T '/le Ball 30 Kg. Load 



Chart 50. — This chart can be employed to determine the approxi- 

 mate tensile strength and percentage elongation of leaded-brasa strip 

 (63.35 % copper, 2.79 % lead, balance zinc) when only Rockwell hard- 

 ness is known. It is accurate for all thicknesses between 0.020 and 

 0.080 in. within the given limits. 



15 



90 



80 



£ 70 



60 



w 



v 



O-50 



40 



,30 



20 



10 

 



QOlO 



0.002 0.004 0.006 Q008 



Strain, Inches per Inch 



Chart 51. — The effect of cold rolling on the stress-strain character- 

 istics of heavy leaded-brass strip (0.040 in. thick) (63.35 % copper, 

 2.79 % lead, balance zinc) having a ready-to-finish grain size of 0.015 

 mm.; 5,000-lb. capacity hydraulic testing machine and Templin 

 automatic extensometer accurate to 0.00001 in. \ised. 



Q002 0.004 0.006 0.008 0.010 



S+rain^ Inches per Inch 



Chart 52. — The effect of cold rolling on the stress-strain character- 

 istics of heavy leaded-brass strip (0.040 in. thick) (63.35 % copper, 

 2.79 % lead, balance zinc) having a ready-to-finish grain size of 0.080 

 mm.; 5,000-lb. capacity hydraulic testing machine and Tetnplin 

 automatic extensometer accurate to 0.00001 in. used. 



