Thiol-functionalised silicone-oils were crosslinked with silver nanoparticles to give mechanically consistent elastomers with high self-healing power. The materials were broken into small pieces and put together in intimate contact for 24 hours at room temperature, observing a complete macroscopic healing and a quantitative recovery of compression-stress and strain.

Cubic boron nitride (cBN)-cemented carbide composites have gained attraction over the last few years because of their potential uses as wear parts. The densification behavior of cBN-hard metal composites by glass encapsulation hot isostatic pressinghas been investigated. Composites with different cBN grades (from 0/0.5 to 6/12 lm particle sizes) and cBN content (up to 50 vol%) were selected for this study. Near-full densification was obtained at temperatures between 11001 and 12001C, and pressures between 150 and 200 MPa, respectively, while no phase transformation of cBN into the low-hardness hexagonal form has been detected by X-ray diffraction. The addition of cBN to the hard metal base material led to an increase of hardness, a significant increase of fracture toughness (K IC measured by Vickers indentation), and a moderate decrease of mechanical strength (determined by three-point bending). cBN, cubic boron nitride; Co, cobalt; WC, tungsten carbide.

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Flow channel inserts (FCIs) are the key elements in the high-temperature dual-coolant lead-lithium blanket, since in this concept the flowing PbLi reaches temperatures near 700 °C and FCIs should provide the necessary thermal and electrical insulations to assure a safe blanket performance. In this paper, the use of a SiCsandwich material for FCIs consisting of a porous SiC core covered by a dense chemical vapor deposition-SiC layer is studied. A fabrication procedure for porous SiC is proposed and the resulting materials are characterized in terms of thermal and electrical conductivities (the latter before and after being subjected to ionizing radiation) and flexural strength. SiC materials with a wide range of porosities are produced; in addition, preliminary results using an alternative route based on the gel-casting technique are also presented, including the fabrication of hollow samples to be part of future lab-scale FCI prototypes. Finally, to study the corrosion resistance of the material in hot PbLi, corrosion tests under static PbLi at 700 °C and under flowing PbLi at ∼10 cm/s and 550 °C, with and without a 1.8-2T magnetic field, were performed to materials coated with a 200-400-µm-thick dense SiC layer, obtaining promising results.

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