High strength alumina tapes prepared by gel-tape casting method

In the current work, high strength alumina (Al2O3) thin tapes were prepared by a novel gel-tape casting method. The water-based slurries were gelled by the polymerization of the epoxy monomers. Low viscosity slurries consisting of nanometer-sized alumina particles were prepared with a solid loading reaching 42 vol%. Sodium and ammonium polyacrylate dispersants were used for alumina particle dispersion and stabilization. The individual Al2O3 tapes reached a relative density of over 99.5% and a grain size between 1.1 and 1.3 mu m after pressureless sintering at 1450 degrees C. The biaxial strength of sintered samples was measured in the ball-on-three-balls setup and the values of characteristic Weibull strength up to 1400 MPa were obtained for as-sintered tapes with a thickness of about 190 mu m. The effect of sodium and ammonium-based polyacrylate dispersants on tape processing and properties of the Al2O3 tapes were investigated and explained.

Automated summary

In this study, high strength alumina thin tapes were prepared using a novel gel-tape casting method. The choice of dispersants and sintering conditions significantly affected the properties of the tapes, with as-sintered tapes showing high characteristic Weibull strength values.