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The isothermal precipitating behavior of perovskite phase in oxidized titanium bearing slag was studied by quenching method. The kinetics of precipitating process and crystal growth of perovskite phase was analyzed. The results show that the precipitating and growth of perovskite are non-equilibrium process at the beginning of isothermal treatment. There are two factors influencing the growth rate of perovskite phase on non-equilibrium condition, one is the supersaturation concentration of perovskite and the other is the coarsening arising from the growth of larger perovskite at the expense of smaller ones. The precipitation kinetics of perovskite phase can be nearly described by the JMAK equation.

The effects of the dynamic oxidation on the viscosity of Ti-bearing blast furnace slag, on a selective enrichment, a precipitation and a growth of the Ti component were studied. The oxygen source was the air that was blown into the molten slag through a lance during the dynamic oxidation process. It was found that the oxidation of TiC, metallic Fe, TiO and Ti 2 O 3 in the slag was not only in favor of the decrease of the viscosity of the slag, but also for the selective enrichment of the Ti component into the perovskite phase as well as the precipitation and growth of the perovskite phase. As oxidation time increases, the precipitation and growth of the perovskite phase rapidly increased, and the slag changed from the melt to a mixture of the melt and crystalline phase(s), that caused the viscosity of the oxidized slag for 12 min increased rapidly.

A high temperature tensile test has been performed at 450 °C with various strain rates and grain sizes for an Al–4Mg–0.4Sc alloy. The experimental results show that the total elongation is strongly sensitive to the grain size and is approximately a linear function of an inverse average grain size. The Portevin–Lechatellier (P-L) effect with significant serrations on the stress–strain curves during tensile deformation at high temperature has been shown to be usual for the Al–4Mg–0.4Sc alloy. The average amplitude of the stress oscillation decreases with increasing strain rate at high temperature.

Tensile test at room temperature has been performed on the Al–4Mg–0.4Sc–1.5Mm (Misch metal) alloy sheet with different reduction rate at crosshead speed of 0.036 mm min−1. The experimental results show that the fracture strain is strongly sensitive to cold rolling reduction rate, and the fracture strain increases with an increase of cold rolling reduction. The Portevin–LeChatellier (P–L) effect with a significantly serrate oscillation of stress–strain curves has been shown to be very regular for Al–4Mg–0.4Sc–1.5Mm alloy during tensile deformation. The onset strain decreases with an increase of cold rolling reduction rate. The average interval and the amplitude of stress–strain oscillation can be described by an exponential function with the strain.

The cavity growth process during superplastic deformation has been studied. A model for this process is proposed based on the theory of grain-boundary-sliding (GBS) and the theory of cavity growth. According to the deduced equation, the relationship between fracture strain and grain size at a specific temperature and strain rate is analyzed and discussed. It shows that the total elongation is an approximated to linear function of the inverse grain size for the superplastic materials.