Many copper-tin alloys are employed for the making of files which, in distinction from the steel files, are designated composition files. Such alloys have the following compositions:

Geneva Composition Files

I         II

Copper........... 64.4      62

Tin.............. 18.0      20

Zinc.............. 10.0      10

Lead............. 7.6        8

Vogel's Composition Files

 

III

IV

V

Copper....

. . 57.0

61.5

73.0

Tin.......

. . 28.5

31.0

19.0

 

.. 78.0

 

8.0

Lead......

.. 7.0

8.5

8.0

VI

Another alloy for composition files is copper, 8 parts; tin, 2; zinc, l,and lead, 1—fused under a cover of borax.