Using severe plastic deformation (SPD) methods to design and fabricate multicomponent materials has been drawing increasing attention in recent years [1, 2]. In the present study, equal-channel angular pressing (ECAP), as the most highly developed SPD technique, is investigated to design and fabricate multicomponent materials for three applications. They are (i) high strength and low density materials for structural application, (ii) high strength, low stiffness and good biocompatibility

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... ls for biomedical implant application, and (iii) high strength and high conductivity materials for electrical transmission line application. Accordingly, this project is divided into three sub-projects, which have the same processing principle of ECAP but different constituents in terms of material selection, shape, and scale of the constituents and the processing parameters. In the first sub-project, multicomponent materials having high strength and low density are aimed to be fabricated using ECAP. Aluminium and magnesium machining chips are used as raw materials. By blending them and consolidating the mixture using ECAP with back pressure of 175MPa, full dense metallic composite is fabricated. Testing results show that substantial improvement of mechanical properties, such as an increase of strength, strain-hardening capability and ductility, can be obtained. This is achieved by changing the strain path, processing temperature and post-ECAP thermal treatment, as well as by optimising the weight fraction of the constituent metals. Microstructure characterisation shows that the strain path can be optimised to achieve profuse breakage of oxide layer along interfaces. Moreover, processing or annealing at 300˚C can cause intermetallic phase formation at the interface resulted from enhanced interdiffusivity. In the second sub-project, multicomponent materials having high strength, low stiffness and good biocompatibility for biomedical implant application are targeted. Three components including titanium, magnesium and silicon [...]