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The Mg–Zn binary alloys prepared by vacuum evaporation were investigated in the initial state and after hot extrusion. The results of X-ray diffraction reveal that the composition of initial state alloys are α-Mg solid solution, MgZn, Mg7Zn3, and MgZn2 intermetallic compounds, respectively. As the compression treatment at the 360 °C (40 min, 10 Mpa), the size of the gray α-Mg phase is reduced from 100 μm to about 50 μm, which is surrounded by white intermetallic. At the same time, the corrosion current density is remarkably reduced, which means that the corrosion performance of the alloy is better. When the hot extrusion time raised from 4 h to 12 h (320 °C, 10 Mpa), the area of the deformation zone increased, and the precipitation amount of Mg7Zn3 distributed α-Mg matrix phases increased. Both the value of CPE1 and Rct are significantly reduced, indicated that the charge harder to transfer and the corrosion resistance of the alloy in Ringer's solution is weakened.

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In the study, Ti fiber (200 μm, 99.8 wt.%) and pure aluminum (99.6 wt.%) were respectively used as the reaction source and matrix to prepare Al-based composites by in-situ synthesis methods. During the stage of preparing the preform, Ti fibers were fixed in the matrix at equal intervals to pre-control the initial position of the product. The preform was heated in an induction heating device finally, at the same time, parameter combinations of different frequencies and currents were applied to promote the in-situ reaction between Al-Ti, thereby the Al matrix composites reinforced by Al3Ti were obtained. The phase composition, microstructure and wear resistance of the composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and wear testers. The results show that when the frequency and current are 5 kHz and 15 A respectively, the Ti fiber is completely reacted, and the product is the isometric Al3Ti with a size of 1 – 2 μm and a particle spacing of about 5 μm, reaching the optimal microstructure under all parameters. Under the condition of a load of 9.8 N, the wear rate of the composites at 5 kHz and 15 A is 2.325 mg/mm2, indicating the best values in this experiment.