Laser stereolithography of ZrO2 toughened Al2O3

• Published in: Journal of the European Ceramic Society Vol. 25; no. 9; pp. 1581 - 1589
• Main Authors: LICCIULLI, A, ESPOSITO CORCIONE, C, GRECO, A, AMICARELLI, V, MAFFEZZOLI, A
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier 01.06.2005
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Ceramic industries; Cermets, ceramic and refractory composites; Chemical industry and chemicals; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Miscellaneous; Other materials; Physics; Specific materials; Technical ceramics; Ceramic matrix composite; Scanning electron microscopy; Dispersion reinforced material; Stereolithography; Experimental study; X ray diffraction; Precursor; Oxide ceramics; Composite material; ZrO2; Laser beam; Technical ceramics; Zirconium Oxides; Manufacturing; Stereolithography; Precursors-organic: Al2O3; Alumina
• ISSN: 0955-2219; 1873-619X
• DOI: 10.1016/j.jeurceramsoc.2003.12.003

Ceramic laser stereolithography is a manufacturing process suitable candidate for the production of complex shape technical ceramics. The green ceramic is produced layer by layer through laser polymerisation of UV curable ceramic suspensions. A number of critical issues deserve attention: high solid loading and low viscosity of the suspensions, high UV reactivity, prevention of interlayer delamination in the green and in the sintered body, good mechanical performance. In this work, ZrO2 reinforced Al2O3 components have been obtained from an acrylic modified zircon loaded with alumina powders. The zircon compound is effective as organic photoactivated resin and allows the dispersion of a high volume fraction of Al2O3 powder (up to 50vol.%) while keeping viscosity at reasonable low values. The zircon compound also represents a liquid ceramic precursor that converts to oxide after burning out of the binder. Thanks to the good dispersion of the alumina powder in the zircon acrylate, a uniform dispersion of ZrO2 submicron particles is obtained after pyrolysis. These are located at the grain boundaries between alumina grains. Formation of both monoclinic and tetragonal ZrO2 occurs as evidenced by XRD. No delamination occurs in bending tests as evidenced by SEM fractography, satisfactory modulus and strength values were concurrently found.