Mechanochemical Activation of Precursor Powders for the Preparation of Dense Al2O3–ZrO2〈Y2O3〉 Nanoceramics

Mechanochemical synthesis of nanostructured and composite oxide ceramics: From mechanisms to tailored properties

“…TA B L E 2Al reduced the porosity of ZTA ceramics, lower the sintering temperature, and improved the bending strength. Al powder increased the intra-grain ZrO 2 content and suppressed the t-m phase transition.Morozova 101,102 synthesized Al 2 O 3 -ZrO 2 powders by mixing different ratios of starting reactants. After grinding and heat treatment, it was found that a phase change occurred, the phase change after the gasification of aluminum chloride became α-Al 2 O 3 and the phase change of zirconium chloride became m-ZrO 2 .…”

Technologies of Coatings and Surface Hardening: Industrial Applications

“…A decrease in temperature-force loading in the cutting zone was 15%-25% and can be explained by the formation of secondary structures on the friction surfaces of aluminum and titanium oxides that were detected by X-ray spectral analysis. As it is known, oxides provide heat-reflecting (shielding) and lubricating properties and exhibit thermochemical inertness and stability up to 800 • C (properties of γ-Al 2 O 3 obtained at 450-600 • C persist up to 800 • C when the formation of a new crystalline phase σ-Al 2 O 3 begins; it forms thermodynamically stable amorphous α-Al 2 O 3 at 850-1000 • C [32,33]; thermal stability of amorphous anatase is up to 500-800 • C and even higher for crystalline rutile). It should be noted that the thermal stability of oxides is determined by Tamman and Hüttig temperatures.…”