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• The densification mechanism of Ti/β-Ti LMCs is sensitive to sintering temperature. • A sintering temperature above 800 ℃ is appropriate to fabricate a densified LMCs. • The α + β dual-phase structure is predominant in the interface layer. • α′ phase and ω phase at the interface enhances the microhardness. Ti/β-Ti laminated composite, which exhibits an exceptional combination of the good ductility of pure Ti and the high strength of the β-Ti alloy, has been extensively applied for biomedical applications. Here, we investigated the densification behavior of the pure Ti layer, β-Ti layer (Ti-15Mo layer), and laminated composite during the fabrication by spark plasma sintering at various sintering temperatures. The experimental results demonstrated that the majority of pores close to sintering necks could be eliminated by sintering at a temperature above 850 ℃, and both the Ti layers and Ti-15Mo layers achieved full densification. When the sintering temperature is below 700 ℃, the sintering is probably achieved by a mechanism of dislocation-climb at low compress stress and by a grain boundary sliding at high compress stress. However, the sintering was likely progressed by the dislocation-climb at 750–800 ℃ and the grain boundary sliding above 850 ℃, respectively. Besides, the influence of sintering temperature on the interfacial characteristics was investigated. The thickness of the interfacial layer was increased from 3 µm to 30 µm with the increase of sintering temperature. An α + β dual-phase structure is formed in the interface layer. The formation of α′ phase and ω phase at the interface of the composite at 1000 ℃ increased the microhardness of the interface, which is harder than the pure Ti and Ti-15Mo alloy. [ABSTRACT FROM AUTHOR]

• FeCoCrNiMoSi x (x = 0.5, 1.0, 1.5) HEAs were fabricated by SPS under 1150 °C. • Hardness of FeCoCrNiMoSi 1.5 reached 1186 HV. • High corrosion potential of Si makes FeCoCrNiMoSi 1.5 exhibits great corrosion resistance. • The oxidation properties FeCoCrNiMoSi 0.5 were greater than that of other FeCoCrNiMo HEAs. • Different properties can be obtained through controlling Si content. FeCoCrNiMoSi x (x = 0.5, 1.0, 1.5) high-entropy alloys (HEAs) were successfully fabricated by spark plasma sintering (SPS). The microstructure, tribological properties, oxidation behaviors and corrosion resistance of the HEAs were systematically investigated. The experimental results showed that the microstructure mainly consisted of Fe-rich face-centered-cubic (FCC) phase, Mo-rich FCC phase solid solution and various Si-rich intermetallics, where the elevated Si content coarsened the primary Mo-rich phase into dendritic eventually. These Mo-rich dendrites possessed strong covalent-dominant atomic bonds that enhanced the microhardness (from 725 to 1186 HV) and wear resistance. The FeCoCrNiMoSi 0.5 HEA exhibited an outstanding combination of relatively high wear resistance and the strongest oxidation resistance under 800 °C among the three alloy compositions. The corrosion resistance of HEAs showed an increasing trend with the elevated Si content, and FeCoCrNiMoSi 1.5 presented the best performance. [ABSTRACT FROM AUTHOR]