Submitted by curator on Fri, 10/16/2015 - 11:48
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Inv. 33-3-125 Awl A cut from the corner of the broader end: magnification, 100x Etchant: Potassium bichromate + alcoholic ferric chloride (Sn, <0.013%; As, 0.23%; Ni, <0.017%) VERY CORRODED
The artifacts top has been corroded to such an extent that only two islands of sound metal remain. In those areas, however, there are large polyhedral grains that, in their twinning and distortion, indicate a treatment of annealing after moderate cold-working. At the center is a cavity that may be the remnant of a casting defect. Inclusions are rough-shaped and in the one area, at least, appear to be concentrated along one band in the microstructure.
Microhardness VHN: 123 ± 13 (n=5) Non-uniform; data scatter (with the VHN ranging 142 to 106) is most likely due to the presence of intergranular corrosion products.
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