Low-Temperature Sintering of Alumina with Liquid-Forming Additives
نویسندگان
چکیده
Simultaneous application of colloidal processing and liquidforming additives to alumina resulted in a sintered density of >99% in 1 h at a temperature as low as 1070°C for a commercial high-purity alumina powder at a total dopant level of 2 mol%. The additives were 0.9% CuO + 0.9% TiOz + 0.1% B 2 0 3 + 0.1% MgO. At higher temperatures or after prolonged sintering, the doped alumina ceramic developed a duplex microstructure containing large elongated grains and exhibited a relatively high fracture toughness of -3.8 MPa-m'" as compared to a value of -2.6 MPa*m'" for the undoped alumina. [
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