770 



BELL SYSTEM TECHNICAL JOURNAL 



TABLE II 

 Physical Tests on Clock-Brass Sheet Rolling Series 



Temper 



Soft 



Quarter 



Hard 



Half Hard 



Hard 



B. & S. 

 Gage 

 Num- 

 bers 

 Hard 



Reduc- 

 tion by 

 Rolling, 

 per 

 cent 



Tensile 



Strength, 



lb. per 



sq. in. 



59,250 

 72,750 

 83,700 

 90,000 

 45,900 

 51,400 



61,800 

 64,500 

 70,200 

 64,600 

 74,300 

 74,800 

 74,500 



Elonga- 

 tion in 

 2 in., 

 per 

 cent 



32 



9 



6 



4 



62 



40 



25 

 23 

 14 

 13 



8.5 



5.5 



Sclero- 

 scope 

 Steel 



Magni- 

 fier 

 Ham- 

 mer, 

 One 



Thick- 

 ness 



35 

 48 

 54 

 58 

 15 

 25 



35 

 40 

 39 



46 

 45 



Rock- 

 well 

 "B" 



Scale, 

 One 



Thick- 

 ness 



80 

 85 

 88 

 21 

 56 



70 

 77 

 78 

 65 

 82 

 84 

 79 



Meyer's 



Analysis 



"A," 



kg. 



106 

 125 

 137.5 

 152 



67 



86 



106 



119 



125 



113.5 



127 



125 



123.5 



material furnished under the Hmits by a number of suppliers. Table 

 V shows the Rockwell hardness limits. Figure 6 shows Rockwell 

 hardness plotted against tensile strength for the high-brass rolling 



Fig. 6 — Relation 



50,000 60.000 70,000 80,000 90.000 100.000 110,000 

 TENSILE STRENGTH — PSI 



of High Brass Rolling Series. Rockwell Hardness to Tensile 

 Strength, Using Standard Rockwell Blocks. 



