Sample Cleaning

Sample Cleaning

Cleanliness is an important requiremet for succefful sample preparation. Specimens must be cleaned after each step, all grains from one grinding and polishing step must be completely removed from the specimen to avoid contamination, which would reduce the efficiency of the next preparation step. Through cleaning is particularly critical after fine grinding and before rough polishing and all subsequent steps. Clean, grease free surfaces are essential for subsequent chemical or electrolytic treatment. Residues, fingerprints, and inconspicuous films may interfere with etching, causing various areas to be attacked at different rates. Every single microsection preparation procedure must be followed by through cleaning, which can be performed in different ways.

Rinsing is most frequently used and consists of holding specimen under a stream of running water and wiping the surafce with a soft brush or cotton swab.

Ultrasonuc cleaning is the most effective and thorough method of cleaning. Not only area surface contaminants removed, but particulate matter held in crevicesm, crack, or pores is removed by the action of cavitation. Usually this ultrasonic cleaning needs only 10 to 30 s.

After cleaning, specimens may be dried rapidly by rinsing in alcohol, benzene, or other low-boiling-point liquids, then placed und a hot-air drier for sufficient time to vaporize liquids remaining in cracks and pores.