210A9034.JPG

Elvan Nermin, BSc. Student 

Metallurgical and Materials Engineering

Yıldız Technical University

 

elvannrmn@gmail.com

https://www.linkedin.com/in/elvan-nermin-836140248/

EFFECT OF WOLFRAM OXIDE OF SODIUM BOROSILICATE BASED INORGANIC COATINGS

Supervisor: Kumru Karaman, Yasin Bozkurt Yılmaz, Assoc Prof. Dr. Buğra Çiçek

Glass ceramic materials are materials obtained by forming a crystal structure inside the amorphous glass. glass ceramics; They are materials that stand out with their high mechanical and thermal properties such as high wear resistance, high chemical stability and low thermal expansion coefficient and are used in advanced engineering applications due to these properties.[1]–[3] The production of glass-ceramics takes place in two stages. The first of these is glass production, followed by a controlled crystallization process in the glass with heat treatment. The crystallization process consists of two stages, first nucleation starts in amorphous structure thanks to nucleating agents and then the nuclei grow to form crystals.[1], [4] Glass-ceramic coating is preferred for coating steel surfaces because it shows better thermal resistance and chemical stability than conventional enamel products. The production of glass ceramic coatings consists of three stages.[5] First, a batch formula is created for frit production, and after the selected raw material is melted with the components, cooling is done. The cooled glass breaks into small pieces. In the second stage, frit is pulverized by adding organsilicone according to the technique of coating. The powdered raw material is coated on the steel with dry and wet coating techniques.[6], [7]. Our aim in this study is to examine the effect of WO3 on the thermal, chemical and mechanical properties of glass ceramic coatings when used in the frit structure and to create a new recipe. WO3 increases the abrasion resistance and chemical resistance of the structure to which it is added. WO3 participates in the structure and lowers the coefficient of thermal expansion, which increases the thermal stability of the structure.[8], [9]

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[2]  W. Höland and G. H. Beall, Glass-ceramic technology, vol. 69, no. 4. 2019. doi: 10.1002/9781119423737.

[3]  M. Rampf, M. Dittmer, C. Ritzberger, M. Schweiger, and W. Höland, “Properties and crystallization phenomena in Li 2 Si 2 O 5 -Ca 5 (PO 4 ) 3 F and Li 2 Si 2 O 5 -Sr 5 (PO 4 ) 3 F glass-ceramics via twofold internal crystallization,” Front. Bioeng. Biotechnol., vol. 3, no. SEP, 2015, doi: 10.3389/fbioe.2015.00122.

[4]  V. Gomes, C. D. G. De Borba, and H. G. Riella, “Production and characterization of glass ceramics from steelwork slag,” J. Mater. Sci., vol. 37, no. 12, pp. 2581–2585, 2002, doi: 10.1023/A:1015468329645.

[5]  E. Scrinzi and S. Rossi, “The aesthetic and functional properties of enamel coatings on steel,” Mater. Des., vol. 31, no. 9, pp. 4138–4146, 2010, doi: 10.1016/j.matdes.2010.04.030.

[6]  F. Russo, S. Rossi, and A. M. Compagnoni, “Porcelain Enamel Coatings,” Encyclopedia, vol. 1, no. 2, pp. 388–400, 2021, doi: 10.3390/encyclopedia1020032.

[7]  L. L. Steele, “49th Porcelain Enamel Institute Technical Forum,” 1987.

[8]  D. Tatar, M. L. Öveolu, and G. Özen, “Effects of CdF 2 and WO 3 additions on the microstructural and thermal properties of TeO 2-CdF 2-WO 3 glass system,” Ceram. Int., vol. 38, no. 3, pp. 1927–1935, 2012, doi: 10.1016/j.ceramint.2011.10.023.

[9]  L. Koudelka, I. Rösslerová, P. Kalenda, P. Mošner, L. Montagne, and B. Revel, Characterization and structural investigation of lead borophosphate glasses modified by tungsten oxide, vol. 658. Elsevier Ltd, 2016. doi: 10.1016/j.jallcom.2015.10.229.