GLASS FORMATION AND PROPERTIES OF CORDIERITE COMPOSITIONS FROM TALC-BASED NATURAL RAW MATERIALS WITH BORON OXIDE ADDITION

Abstract

In this study, the glass forming behaviour of cordierite compositions in MAS (MgO-Al₂O₃-SiO₂) system with added B₂O₃ content up to 3% were studied by melting the natural raw materials such as; talc, kaolin, alumina and boric acid as the source of MgO, SiO₂, Al₂O₃ and B₂O₃ respectively. XRD analysis revealed the glass formation. Optical properties of the glasses were measured using UV-VIS spectrophotometer and structural changes were monitored by using FT-IR spectrometer. Physical properties such as density, colour, thermal expansion coefficients and hardness were measured according to the standard test methods. Glasses with a green colour were produced and this was attributed to the Fe content in the glass up to 0.5% coming from talc and kaolin. The addition of B₂O₃ to the glasses increased the glass transition temperatures (T_g) values and reduced the thermal expansion coefficient values of the glasses from 5.2226 to 5.0072 (ºCx10^-6), for MAS-T-0 and MAS-T-3, respectively.

 

Keywords: Green glass, Colour, Glass-formation, Natural raw materials, Optical properties.

Keywords

• -

BOR OKSİT İLAVESİ İLE TALK-ESASLI DOĞAL HAMMADDELERDEN KORDİYERİT CAMI OLUŞUMU VE ÖZELLİKLERİ

Abstract

Bu çalışmada, SiO2, MgO, Al2O3 ve B2O3 kaynağı olarak sırasıyla kaolin, talk, alumina ve borik asit gibi doğal malzemelerin eritilmesi ve %3’e kadar B2O3 ilavesi ile MAS (MgO-Al2O3-SiO) sistemindeki kordiyerit kompozisyonlarının cam oluşturma davranışı incelenmiştir. Camların optik özellikleri UV-VIS spektrofotometre ve yapısal analizler FT-IR ile belirlenmiştir. Yoğunluk, renk, termal genleşme katsayısı ve sertlik gibi fiziksel özellikler standart test metotlarına göre ölçülmüştür. Talk ve kaolendeki %0.5’e kadar olan Fe içeriği nedeniyle, yeşil renkli camlar elde edilmiş ve B2O3 ilavesi cam geçiş sıcaklığı (Tg) değerlerini yükseltmiştir ve MAS-T-0’dan MAS-T-3’e doğru termal genleşme katsayısını 5.2226’dan 5.0072ºCx10-6’ye düşürmüştür.

Keywords

• Yeşil cam, Renk, Cam oluşumu, Doğal hammaddeler, Optik özellikler

References

1. Ardelean, I., Ciorcas, F., Peteanu, M., Bratu, I. and Ioncu, V. (2000). The structural study of Fe2O3-TeO2-B2O3-SrF2 glasses by EPR and IR spectroscopies. Modern Physics Letters B14, 17-18, 653-661.
2. Arutyunyan, N.M., Knyazyan, N.B., Toroyan, V.P. and Kostanyan, K.A. (1997). Perlite- based glasses. Glass and Ceramics 45 (9- 10), 311-312.
3. Boroica, L., Radu, D. and Medianu, R. (2008). FTIR spectra of glasses from BaO-B2O3- TiO2 system. Journal of Optoelectronics and Advanced Materials 10,(12), 3217 – 3220.
4. Gunay, V. (1990). Sol-gel processing of fibre reinforced glass and glass-ceramic matrix composites, PhD Thesis, The University of Sheffield, England.
5. Kamitsos, E.I. and Chryssikos, G.D. (1991). Borate glass structure by Raman and infrared spectroscopies. J. Molecular Structure 247, 1-16.
6. Kamitsos, E.I., Karakassides, M.A. and Cryssikos, G.D. (1987). Vibrational spectra of magnesium-sodium-borate glasses: 2. Raman and mid-infrared investigation of the network structure. J. Phys. Chem. 91, 1073-1079.
7. Papadopoulos, N.S. and Moutsatsou, A.K. (2003). Influence of coloured culled dur- ing production of amber glasses. Glass Technol. 44(3), 123-127.
8. Opera, C., Stan, C., Rotiu, E. and Propescu, C. (1999). Non-isothermal crystallization of cordierite glasses, Journal of Thermal Analysis and Calorimetry 56, 611-615.

9. Zhernovaya, N.F., Onishchuk, V.I. and Davy- doglu, B. (2007). Color control and redox balance monitoring in container glass Glass and Ceramics 64(3-4), 111-114.
10. http://serc.carleton.edu/images/research_educati on/equilibria/masfields.jpg