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To balance the paradox of both high mechanical properties and electrical conductivity of copper alloys, a nominal hot-rolled Cu-0.4 wt.%Cr-0.3 wt.%Zr alloy strips were subjected to different thermo-mechanical process. The microstructures of the alloys are characterized by optical microscopy and transmission electron microscopy and the mechanical properties and the electrical conductivity are evaluated. The results show that a desired combination of strength, ductility and conductivity can be obtained by controlling the sequence of cold rolling and aging. It suggests that the treatment route with an order of aging followed by cold rolling (ACR) is better than that with the order of cold rolling with aging (CRA). The ultimate tensile strength 568 MPa and electrical conductivity 75.3%IACS are obtained after aging at 450 °C for 3 h followed by 80% cold rolling at room temperature. The high electrical conductivity and ductility is attributed to twin lamellar structure.

In this paper the oxidative degradation process of methyl vanillin wastewater was studied by the subcritical water oxidation (HCWO) technology. A subcritical Fenton oxidation (HCFO) system formed while Fe2+ was added as a catalyst. The oxidation degradation kinetics of methyl vanillin wastewater was also studied. The results showed that the suitable process conditions for degradation of methyl vanillin wastewater by HCWO were as follows: temperature of 340 ​°C, pressure of 24 ​MPa, oxidant multiple of 1.5, residence time of 217.3 ​s (flow rate of 2.0 ​mL ​min-1). For methyl vanillin wastewater, the HCFO system has no obvious advantages compared to the HCWO system. The activation energy (Ea) of HCWO oxidized methyl vanillin wastewater reaction was 32.6 ​kJ ​mol-1, and the pre-exponential factor A was 5.64 s-1.

The wide applications of pure titanium (Ti) are greatly limited by its low strength and hardness. In this paper, we employed an industrial method of rotary swaging (RS) to improve the strength of commercial pure (CP) Ti and uncovered the elementary mechanisms governing microstructural changes under RS. Specifically, the {10-12} extension and {11-22} contraction twins take place in the coarse grains at the early stage of RS deformation, which contributes to the increase of yield strength and moderate ductility. As for the late stage, the twins disappear and are replaced by textured nanostructured grains; meanwhile, there exists a hardness gradient along the radial sample direction. High strain rate RS brings about profuse twins and rapid grain refinement at room temperature in contrast to conventional severe plastic deformation. We rationalize that the high yield strength of CP Ti (up to 955 MPa) is attributed to dislocation, grain boundary and texture strengthening. This result may provide some insights in microstructure-based design of metals with superior mechanical properties subjected to this scalable RS technique.