Submitted by curator on Fri, 10/16/2015 - 13:37
 |
|
Inv. 31-52-185
Flat ended toggle pin
A cut across the broken lower end of one arm: magnification, 200x
Etchant: Klemms III
(Sn, <0.009%; As, 0.51%; Ni, 0.077%)
The metal is heavily penetrated by pitting and intergranular corrosion, but in sound regions there are twinned polyhedral grains that are the result of annealing of the previously cold-worked metal. Inclusions occur in clusters that might suggest the presence of a second phase that most likely are remnants of non-metallic material (matte) that became entrapped in the copper during its original smelting.
Microhardness VHN: 79 ± 7 (n=5)
Uniform; data scatter (with the VHN ranging 88 to 70) is most likely due to the presence of intergranular corrosion products.
|
