The modulated structure of the AlCrFeCoNiCu high‐entropy alloy consists of NiAl intermetallics (β′) and a (α‐Fe, Cr) solid solution (β). The formation of the NiAl intermetallics greatly affects the strengths and magnetic properties of the AlxCrFeCoNiCu alloys. Evidently, the AlCrFeCoNiCu alloy cannot be treated as a solid‐solution alloy.

Titanium alloy castings are made by means of induction melting technology. The relationships thickness of lamellar α+β phase and tensile strength, yield strength, elongation percentage, and Vickers-hardness, as well as the effect of tensile property on the Vickers-hardness are investigated for Ti-6Al-4V alloy castings. The results show that the relationships between thickness of lamellar α+β phase, and tensile strength, yield strength, specific elongation, and Vickers-hardness meet the Hall-Petch equation. And the tensile property increases linearly with Vickers-hardness.

The wettability between liquid Ti-50Al (at.%) (TiAl) and calcia-stabilized zirconia (ZrO2 (CaO)) in the gravity field and/or electromagnetic fields was studied in argon atmosphere. The results show that the equilibrium contact angle between liquid TiAl and ZrO2 (CaO) decreased from 63° in the gravity field to 50° in the electromagnetic field. However, the time required for the system to achieve equilibrium in the electromagnetic field was 16s, which was longer than that in the gravity field. The effect of the electromagnetic field on the wettability between TiAl and ZrO2 (CaO) was explained by the total free energy at the liquid/solid interface and activity of Ti element.

By applying ultrasonic solidification, gypsum based micro casting mold with different chemical compositions were sintered at different temperatures. The influence of processing parameters and sintering temperature on the microstructure and surface roughness were investigated. Meanwhile, the effect of sintering temperature on the bending strength was studied. The result showed that the nucleation rate of gypsum can be significantly improved under high temperature and pressure, which was caused by the effect of ultrasonic cavitation. Under the frequency of 100 KHz and the power of 200 W, 20 min, the morphology of gypsum transfers from flake and needle into near spherical after 20 min, and the grain size can be refined to around 500 nm. The value node of surface roughness occurs at the sintering temperature of 600 °C. The surface roughness is the lowest when the gypsum content is 60% and under the sintering temperature of 600 °C, which can reach Ra ~ 0.22 um. The bending strength of mold roughly increased with the increase of content of gypsum. There is no obvious rule for the mold strength with the change of sintering temperature. The mold strength reaches the highest value when the sintering temperature is 600°C.

Ti-6Al-4V alloy castings are made by means of induction melting technology. The relationships between grain size and tensile strength, yield strength, elongation percentage, investigated for Ti-6Al-4V alloy castings. The results show that the relationships between grain size, and tensile strength, yield strength, specific elongation, meet the Hall-Petch equation.

In this work, the effects of centrifugal radius and mould rotation speed on the tensile strength, yield strength, specific elongation, and microhardness on Al-Cu alloy castings are investigated. The results show that, with increasing the centrifugal radius or mould rotation speed, the mechanical properties increase gradually. With increasing the centrifugal radius, the variation amplitude of mechanical properties of Al-Cu alloys at mould rotation speed 600rpm is greater than that at 300rpm. This is due to the finer microstructure and the strengthened grain boundary and then resulting in the increase of the resistance to dislocation slipping.

The wettability between pure liquid titanium and calcia-stabilized zirconia was studied in argon atmosphere. The micrographic observations made on cross section perpendicular to the interface using SEM showed that interfacial reaction occurred. However, the contact angles were larger than 90°within experimental duration.