Phase diagram of the Al2O3–ZrO2–La2O3 system

The Al2O3–HfO2–La2O3 phase diagram. II. phase equilibria at 1250 and 1600°C

“…Regarding the constitution of the above-described sections and similar isothermal sections of the Al 2 O 3 -ZrO 2 -La 2 O 3 phase diagram [2,3], note that interactions in the Al 2 O 3 -HfO 2 -LH 2 -LA quadrangle in the system with HfO 2 are fundamentally different. The ZrO 2 -LA equilibrium is stable in the system with ZrO 2 and LH 2 -AL [2,3].…”

“…The ZrO 2 -LA equilibrium is stable in the system with ZrO 2 and LH 2 -AL [2,3]. A major difference of the system in question from the system with ZrO 2 is that the M-HfO 2 phase, instead of T-ZrO 2 , is in equilibrium with the respective phases in the Al 2 O 3 -HfO 2 -La 2 O 3 system.…”

“…The pallets were annealed in air in a ShP-1 furnace with silit heaters at 900°C to remove organic substances and promote partial interaction of the mixture components. The latter is especially important since free La 2 O 3 must be bound in binary compounds and solid solutions to avoid the reaction of free La 2 O 3 with moisture to form La(OH) 3 and destroy the pallets.…”

“…The data on the Al 2 O 3 -ZrO 2 -La 2 O 3 system [2,3] testify that the isothermal sections hardly differ after the samples are annealed at different temperatures.…”

The Al2O3–HfO2–La2O3 phase diagram. I. Liquidus and solidus surfaces

“…95% base material produced at the Donetsk Chemical Reagent Plant, and La 2 O 3 of OSCh LaoD grade (as per OST-48-194-81).Table 1shows compositions of the samples. The powders were chosen using data on their interaction in the Al 2 O 3 -ZrO 2 -La 2 O 3 system[13,14]. Prior to weighing, the Al 2 O 3 and HfO 2 powders were annealedTABLE 1.…”