136 



Tables 80 and 81 

 ELASTIC MODULI 



TABLE 80. — Rigidity Modulu6 



If to the four consecutive faces of a cube a tangential stress is applied, opposite in direction on 

 adjacent sides, the modulus of rigidity is obtained by dividing the numerical value of the tangential 

 stress per unit area (kg per sq. mm) by the number representing the change of angles on the 

 non-stressed faces, measured in radians. 



Substance. 



Aluminum 



Brass 



cast 



" cast, 60 Cu-(- 12 Sn 

 Bismuth, slowly cooled . . 

 Bronze, cast, 88 Cu -f- 12 Sn 

 Cadmium, cast . . . 

 Copper, cast 



Gold 



Iron, cast 



Magnesium, cast 

 Nickel . . . . 

 Phosphor bronze 



Rigidity 

 Modulus. 



335° 



25S0 



355° 

 3715 

 3700 

 1240 

 4060 

 2450 

 4780 

 4213 

 445° 

 4664 

 2850 



395° 

 5210 

 6706 



7975 

 6940 

 810S 



75°5 

 1710 

 7820 

 4359 



Refer- 



14 



5 



10 

 11 



5 

 5 

 5 

 5 



18 

 10 

 19 



5 

 14 



5 



15 

 10 



7 

 16 



14 



5 

 5 



IT 



Substance. 



Quartz fibre 

 Silver . . 



" hard-drawn . 

 Steel 



" cast . . . . 



" cast, coarse gr. 



" silver- . . . 

 Tin, cast . . . . 



Zinc . . 

 Platinum 

 Glass 



Clay rock 

 Granite . 

 Marble . 

 Slate 



Rigidity 

 Modulus. 



2380 

 2960 

 2650 

 2566 

 2816 

 8290 



7458 

 8070 

 7872 

 1730 



J 543 

 3880 

 3820 

 66 w 

 6220 

 2350 



2730 

 1770 

 1280 

 1 190 

 2290 



References 1-16, see Table 48. 



17 Gratz, Wied. Ann. 28, 1886. 



18 Savart, Pogg. Ann. 16, 1829. 



19 Kiewiet, Diss. Gottingen, 1886. 



20 Threlfall, Philos. Mag. (5) 30, ii 



Refer- 

 ence. 



20 



21 



5 

 10 



16 



II 



16 



!5 



5 

 11 



5 

 19 



5 



J 9 

 16 

 22 



21 Boys, Philos. Mag. (3) 30, 1890. 



22 Thomson, Lord Kelvin. 



23 Gray and Milne. 



24 Adams-Coker, Carnegie Publ. No. 46, 



1906. 



TABLE 81. — Variation ox the Rigidity Modulus with the Temperature 



;/, = ;/„ ( 1 — at — fit- — yt 3 ), where / = temperature Centigrade. 



Smithsonian Tables. 



* Modulus of rigidity in 10 11 dynes per sq. cm 



