|
|
![]() |
| Page 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | ||||||||||||||
| REVERE COPPER AND ITS ALLOYS | ||||||||||||||
|
||||||||||||||
| Metals most commonly alloyed with copper are zinc, tin, aluminum, silicon and nickel. Of the various alloys,
the brasses (copper and zinc in varying percentages) are the best known. The brasses commonly used range from 95% copper—5% zinc to about 55% copper—45% zinc. This range may be divided into those brasses with a copper content above approximately 64% and those with less than this percentage of copper. The former are known as the “alpha" brasses, the latter as “beta” brasses. Actually this means a mixture of alpha and beta brass, since all beta is uncommon. The alpha brasses are best known for their ability to withstand a great deal of cold working (drawing, rolling, etc.) without annealing. In this respect they closely resemble copper. They show somewhat higher strength than copper—this increasing with the decrease in copper content. Their ductility is good—the combination of ductility and strength being even better than that of copper. These brasses may also be hot worked although in this respect they are slightly, by modern standards, inferior to the beta brasses. Their corrosion resistance is reasonably good yet in some respects inferior to copper; depending upon conditions. The electrical and heat conductivity is fair—again decreasing with the decrease in copper content. These brasses exhibit a wide range of colors—from the red-gold of 95% copper-5% zinc through the gold of 90% copper-10% zinc and 85% copper-15% zinc to the bright yellow shown at 70% copper. Some of the common alpha brasses and their commercial names are: |
||||||||||||||
|
Gilding, 95% (210)* |
||||||||||||||
| *These and subsequent numbers used in parenthesis (without prefix letters such as “B”, etc.) throughout this booklet, are employed by the Copper Development Association, Inc. to identify the various copper alloys. For example: those with more than 93% copper are numbered 100 to 199 while non-leaded brasses are 200 to 299. | ||||||||||||||
|