METAL AND OVERGLAZE SINTERING IN A SINGLE FIRE APPLIED TO THE SPECIAL PARTS INDUSTRY

Abstract

In the present study, the characteristics of sintering of metal and overglaze in a single firing was verified. For that, it was collected 5 samples of overglaze from different glazing companies in the South region of Brazil, which were characterized by chemical analysis, coefficient of linear thermal expansion by dilatometry, and draining button (glaze melt flow) test. Then, the overglazes were applied in the as-received condition and after milling for 5 and 10 minutes; the powders were characterized by particle size distribution analysis. Overglaze layers mixed with gold powder were applied to ceramic plates with mass of 0.5 and 1.0 g, and sintering was performed at four different temperatures (800°C, 850°C, 900°C and 950°C) with 60 minutes firing cycle. Finally, the following tests were performed: visual analysis, light microscopy, colorimetry, and Mohs hardness. With the results of this work, samples with brightness and color characteristics close to the standard commercial product produced in multiple firings could be obtained. In the scratch resistance (Mohs hardness), the result was one point above the standard, indicating a better quality and durability of the material.

Keywords

• Overglaze; Sintering; Single firing.