The Brasses 



61 



-;I20 

 (y 



olio 

 o 



m 100 

 E 90 



_J 



>^ 80 

 o 



u- 70 

 I 



1 60H 

 > 50 



w 



w 40 



30 



V. 20 



CR 400 500 600 700 800 900 1000 1100 1200 1300 

 Annealing Temp. in Deg.F (IHr.at Temp.) 



Chabt 98. — The effect of annealing on the Rockwell hardness and 

 percentage elongation in 2 in. of 70-30 (cartridge brass) strip, previously 

 cold-rolled 6 B. & S. Nos. (50 per cent reduction of area) from two 

 different grain sizes, 0.015 and 0.070 mm. (69.83 % copper) (0.040-in. 

 stock). 



100 



90 



80 



. 70 

 & 60 



Qj 50 



40 



5. 30 



20 



400 500 600 700 800 900 1000 1100 1200 1300 

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



Chakt 99. — The effect of annealing on the yield strength of 70-30 

 (cartridge brass) strip, previously cold-roUed 6 B. & S. Nos. (50 per cent 

 reduction of area) from a grain size of 0.015 mm. (69.83 % copper) 

 (0.040-in. stock). 



90 



80 



70 



t 60 



D" 



^ 50 



u 



lU 



CI- 40 



o 30 

 o 

 o 

 -' 20 



400 500 600 700 800 900 1000 1100 1200 1300 

 Annealing Temp.in Deg.H (IHr. at Temp.) 



Chart 100. — The effect of annealing on the yield strength of 70-30 

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

 reduction of area) from a grain size of 0.070 mm. (69.83 % copper) 

 (0.040-in. stock). 



no 



^ 100 



C Q. 80 



+ -^ 

 C -" 70 



u o 



i;2 60 



D. p 



c 



5j: 50 

 40 

 30 



cntu 

 c 1- 



0) 



10 20 30 40 50 60 70 80 90 100 



Rockwell Hardness B-'/i6 Ball 100 Kg. Load 

 57 63 69 74 80 86 91 97 - - - 



Rockwell Hardness F-'/ieBall 60Kq.Lodd 

 64 67 71 74 77 80 84 87 90 93 



Rockwell Hardness l5T-'/i6Ball 15 Kg. Load 

 22 29 36 43 50 57 64 70 76 82 

 Rockwell Hardness 30 T- '/le" Ball 30i<:g. Load 



Chakt 101. — This chart can be employed to determine the approxi- 

 mate tensile strength and percentage elongation of 70-30 (cartridge 

 brass) strip (69.83 % copper) when only Rockwell hardness is known. 

 It is accurate for aU thicknesses between 0.020 and 0.080 in. within 

 the given limits. 



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