Surface Contamination of Alumina Ceramics by Carbon
نویسندگان
چکیده
Article history: Received: 01.05.2016. Received in revised form: 25.07.2016. Accepted: 06.09.2016. This study presents the results of investigating the cause of contamination of aluminum oxide ceramics (Al2O3) in the form of brown colored stain. Contaminated ceramic surfaces were examined with the scanning electron microscope (SEM) equipped with the Energy Dispersive Spectrometer (EDS). The results show the existence of the carbon in contaminated surface that does not exist in the basic raw materials composition, not even in traces. To determine the place and source of contamination, the investigations of the production process were carried out by stages. It was found that the semifinished product occurs in contact with carbon at two stages in the manufacturing process; by sintering semi-finished product on carbon plates and cooling with emulsion that contains carbon in traces during cutting. It was shown that contamination occurs in contact with alumina ceramics sintered on carbon plates.
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