| (a) Process.-
The copper shall be fire-refined or electrolytic and hot-rolled
from suitable cakes.
(b) Chemical Composition.- The chemical composition
of the plates shall be as follows:-
|
Per cent. |
| Copper |
99.2 minimum |
| Arsenic |
.30 to .50 |
| Antimony |
0.05 maximum |
| Bismuth |
0.05 maximum |
| Oxygen |
0.10 maximum |
(c) Freedom from defects.- The plates
shall be clean, smooth and free from defects and shall have
a workmanlike finish. They shall be thoroughly annealed.
(d) Rolling Margin.- No plate shall
be under the specified thickness at any part, not more than
5% over the calculated weight. The scrap margin, partly sheared
and left attached, shall be not less than 3 inches at the
ends and 1½ inches at each side.
(e) Tensile Tests.- One tensile test
shall be taken from each plate as rolled.
The tensile breaking strength, from Standard Test Piece A,
shall not be less than 14 tons per sq. inch with an elongation
of not less than 35%.
(f) Hot and Cold Bend tests.- One
hot (temperature between 1200°F and 1400°F) and one
cold bend test shall be taken from each plate as rolled.
For either hot or cold bend tests, the test piece shall withstand
being doubled over without fracture until the sides are touching
and parallel.
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