Fabrication, microstructure and mechanical properties of co-continuous TiCx/Cu-Cu4Ti composites prepared by pressureless-infiltration method.

Abstract The co-continuous TiC x /Cu-Cu 4 Ti composites were prepared by infiltrating melting Cu into TiC 0.5 porous preforms. TiC 0.5 porous preforms were firstly synthesized by in-situ solid reaction process using powder Ti and carbon black as the starting materials, PVB as shaping and pore-forming agent. The prepared TiC 0.5 preforms showed 3D-connected visible pores characterized with two classes of sizes, i.e. intergranular pores with size of 10–30 µm and intracrystalline pores with 2–3 µm. Microstructure and phase compositions of the composites were detected by scanning electron microscopy (SEM) equipped with EDS and X-ray diffraction (XRD). Metal region of the composites contained Cu as well as a new phase Cu 4 Ti, which was formed by reaction of Cu and TiC 0.5. Composites prepared by this method had a compact structure and strong interface. Meanwhile, metal phase and ceramic phase maintained a co-continuous structure in three dimensions. Cu-Cu 4 Ti entered into the TiC x ceramic particles like root structure during the infiltration process. Flexural strength, fracture toughness and Vickers hardness of the composites reached 948.20 ± 124.04 MPa, 12.62 ± 0.37 MN m−3/2 and 606.4 ± 36.7 respectively when content of TiC x was 71.22 vol%. [ABSTRACT FROM AUTHOR]