Mechanical properties and thermal expansion behaviour in leucite containing materials

• Published in: Journal of materials science Vol. 29; no. 1; pp. 125 - 128
• Main Authors: TZER-SHIN SHEU, O'BRIEN, W. J, RASMUSSEN, S. T, TSENG-YING TIEN
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 1994
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Ceramic industries; Chemical industry and chemicals; Exact sciences and technology; Miscellaneous; Technical ceramics; Phase composition; Temperature effect; Mechanical properties; Dental ceramics; Experimental study; Potassium silicate; Thermal properties; Bending strength; Thermal expansion; Aluminium silicate; Multi-element compounds; Sintering; Biomaterial; Manufacturing
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/BF00356582

The effect of a change in sodium content and thermal history on a leucite composition material produced by a coprecipitation process was studied. Five materials with formulae of (K(1-x),Nax)2O.Al2O3; 4SiO2 (x = 0.0, 0.2, 0.4, 0.6, 0.8) were investigated for differences in phases, thermal expansion and strength. Strengths of up to 175 MPa were obtained for a leucite composition material (x = 0.0). Sodium was effective in lowering the thermal expansion coefficients of these materials. Leucite was linked to higher flexural strengths, but was present only in those specimens which were sintered at 1200 C. It was not present in those specimens sintered at 1100 C or lower. Porosity was present in all specimens sintered at 1000 C or higher. These materials are used as dental ceramics in posterior crowns. 18 refs.