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Although filled skutterudites are very promising thermoelectric (TE) materials at intermediate temperature, most of the high-performance skutterudites reported are multiple-filled materials that tend to have poor stability and machinability. Here, we successfully fabricate single-filled skutterudite based composites with uniformly dispersed β-SiC nanoparticles via cryogenic grinding and spark plasma sintering. The nanocomposites show not only increased Seebeck coefficient owing to a possible energy filtering effect, but also reduced lattice thermal conductivity through enhanced phonon scattering. A maximum ZT value of 1.42 at 850 K with greatly improved mechanical properties is achieved, which is very attractive for the application in TE devices.

We successfully fabricated a controllable intragranular pore containing hydroxyapatite (HA) by the combination of an electric current assisted sintering and pre-heat treatment process. The microstructure and mechanical properties of the sintered HA bulk with and without intragranular pores were investigated in this study. Fully densified HA fabricated by the combination of an electric assisted sintering and pre-heat treatment process showed extremely superior mechanical properties. Meanwhile, hierarchically structured porous HA consisting of nanosized intragranular pores without macropores in the grain boundary showed dramatically decreased elastic modulus by different fracture mechanism compared with fully densified HA.

A new method for determining the viscosity of the supercooled liquid region of metallic glasses by means of a single-particle compressive test (SPCT) is proposed. A spherical metallic glassy particle several hundred micrometers in diameter is uniaxially pressed using a precisely controlled micro-hot-pressing system. Assuming viscous flow of the material, we derived the viscosity as a function of compressive load and displacement under a constant crosshead speed. SPCT is effective in evaluating metallic glass viscosity regardless of glass forming capability.

The thermal conductivities of carbon nanotube (CNT)–copper (Cu) composites are greatly increased for compositions containing up to 1 vol.% CNT and remain above the value for pure Cu up to 3 vol.% CNT. The obtained enhancement was in good agreement with estimates based on Eshelby’s equivalent inclusion method. This agreement suggests that very low thermal resistance might be realized at the interface between CNTs and the Cu matrix, which consists of faceted and closely attached interface without any compounds.

Heteroaggregation is employed in a controlled way to the mass-production of individually alumina-decorated multi-walled carbon nanotubes (CNTs) with optimized and controlled compositions, with the aim of obtaining reinforced homogeneously dispersed CNT–alumina matrix nanocomposite after spark plasma sintering. The homogeneous composites can only be obtained for CNT concentrations in the range 2.4–16 vol.%. Irreversibility of decoration is examined, and homogeneity of the composite is further investigated, based on supernatant transparency proposed in our approach.

A Co–V alloy and three kinds of PdNi–Cr–V alloys were designed for SiC joining. A wetting experiment was conducted with the sessile drop method. The interface reactions are discussed. Vanadium was found to be effective in controlling of the interface reaction.

Multiwalled carbon nanotubes (CNTs) have been employed for the first time to fabricate bulk, layered, nanostructure-controlled functionally graded (FG) alumina ceramics using a recently established powder technology. Gradual and homogeneous incorporation of the CNTs within the alumina ceramic shows promise to effectively cause in-depth gradients in microstructure, grain size and hardness. The FG concept offers the potential to successfully bridge conventional ceramics to their nanocomposites containing a high concentration of CNTs.