Fig. 1 TEM micrographs of extruded Mg-10 vol.% SiCnp (M10Sn): a uniform distribution of SiCnp in Mg matrix corresponding to the EDS spectra of marked circles, b dark field showing dynamic recrystallisation (DRXed) grains, c high-resolution transmission electron microscopy (HRTEM) of interface between SiCnp, Mg matrix, d statistical grain size distribution [60]

Fig. 2 Microstructure of sintered Mg-TiC-MoS2 hybrid composites: a Mg-5TiC-5MoS2, b Mg-5TiC-10MoS2, c Mg-10TiC-5MoS2, d Mg-10TiC-10MoS2 [70]

Fig. 3 XRD patterns of microwave and spark plasma sintered specimens [76]

Fig. 4 SEM images of a as-received Ni-coated CNTs, b pure Mg powder, c refined Mg powder, d mixture of Mg and CNTs powders [79]

Fig. 5 Scheme of the preparation process of the CNT-Al2O3/Mg composite: a in situ synthesis of CNT-Al2O3 synergistic reinforcements by CCVD, b the obtained urchin-like CNT-Al2O3 synergistic reinforcements, c preparation of CNT-Al2O3/Mg mixed powders, d preparation of the bulk CNT-Al2O3/Mg composite by cold pressing, e preparation of the final CNT-Al2O3/Mg composite by sintering and hot extrusion [84]

Fig. 6 Schematic of the hierarchical Mg matrix nanocomposite synthesized in this study [88]

Fig. 7 Schematic diagram of microstructure of as-extruded composite formed by powders of different shapes [89]

Fig. 8 a Morphologies of the SiCp and raw Mg powders. b Morphologies and sectional observations of the composite powders revealing a core-shell structure forming after milling for 20 h and a homogeneous structure forming after milling for 40 h. c Microstructure of the bulk composites fabricated from the core-shell structured and homogeneous powders [90]