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The in situ nano-TiC x /Al–Zn–Mg–Cu composites with different TiC x content (20, 25 and 30 vol.%) were successfully fabricated by combustion synthesis and hot press consolidation in Al–Ti–C/CNTs systems. The compressive properties and abrasive wear resistance of the composites improved with the increase in the TiC x content. The transformation of carbon source from pure C black to the mixture of C black and CNTs to pure CNTs in Al–Ti–C/CNTs systems leaded to a significant improvement in the compressive properties and wear resistance of the composites as well as a significant decrease in the average size of TiC x particles. The average size of the nano-TiC x particles in 30 vol.% TiC x /Al–Zn–Mg–Cu composite synthesized by the carbon source of CNTs reached 81 nm, moreover, the yield strength ( σ 0.2 ), the ultimate compression strength ( σ UCS ) and the fracture strain ( ɛ f ) of the composite reached 597 MPa, 882 MPa and 21.7%, respectively. [ABSTRACT FROM AUTHOR]

Inspired by nacre, we designed biomimetic metal–ceramic composites in which hard and ductile phases were alternately arranged. We first prepared lamellar-structured TiC scaffolds with 25, 30 and 35 vol% solid loadings using a unidirectional freeze casting technique and then measured wetting and infiltration dynamics for a commercial Al cast alloy, ZL107, with the main composition of Al–7Si–5Cu on the porous TiC scaffold using a modified sessile drop method at 850 °C. The wetting was affected by liquid spreading at horizontal surface and infiltration in depth, while the latter played a dominant role in the decrease in contact angle. On the basis of the wetting results, the lamellar ZL107/TiC composites were successfully fabricated by pressure infiltration of the molten ZL107 alloy into porous TiC scaffolds and their mechanical properties were evaluated. The compressive strength and elastic modulus increased while bending strength decreased with increasing TiC content, giving maximum values of 1166 ± 20 MPa, 205 ± 2 GPa and 363 ± 5 MPa, respectively. Formation of (Al m ,Si 1 − m ) 3 Ti, Al 3 Ti and Al 4 C 3 phases in the composites was presumed to deteriorate the toughness of the composites, leading to brittle fracture under loading. [ABSTRACT FROM AUTHOR]

The (micron+nano) bimodal sized SiC p /Al2014 composites fabricated by semi-solid stirring exhibited fine α-Al grains, well-dispersed bimodal sized SiC p and well-bonded interface between SiC p and matrix. The yield and ultimate tensile strength of the extruded bimodal sized SiC p /Al2014 composites were significantly enhanced, compared to the extruded single-sized SiC p /Al2014 composites. [ABSTRACT FROM AUTHOR]