Microscopic Examination Essay

This essay has a total of 372 words and 2 pages.

Microscopic Examination

MICROSCOPIC EXAMINATION OF METALS
In this experiment, our aim is examining the microstructure of metals. By studying
microscopic structures of metals, we determine which material fits best to a given
application. We used the most common method, optical technique, to examine the
microstructure.

We used a small specimen cut from the metal to be examined. To be able to see the
structure clearly, we first cleaned and polished the specimen. First we start polishing
with emery paper no: 1 and some finer grades. One should be careful about the coarse
abrasive particles and striations from them. Cleaning and rotating the specimen 90 during
the transfer can prevent these. The next step is polishing, yet washing the sample before
polishing gives a more successful result. Finally, we polished the specimen on a rotating
cloth covered with an effective abrasive like Al2O3-Water suspension. We kept polishing
until we obtained a mirror like face.

After we finished polishing, the crystalline structure of the specimen, any cracks, seams,
non-metallic inclusions and inhomogenities, could be revealed. Before start etching we
first applied mounting process. In this step we used a matched die set. We placed our
sample into the die set in the way that the rough face of the specimen was the lower
surface and the polished face looked upward. We filled the die cavity with Bakelite and
then we transferred our die to a mounpress. Mounting not only protects our sample but also
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