Synchrotron X-ray imaging has been used to examine in situ the deformation of dendrites that takes place during the solidification of a nickel-based superalloy. By combining absorption and diffraction contrast imaging, deformation events could be classified by their localization and permanence. In particular, a deformation mechanism arising from thermal contraction in a temperature gradient was elucidated through digital image correlation. It was concluded that this mechanism may explain the small misorientations typically observed in single crystal castings.

These studies demonstrate that human corneal epithelial cells are capable of rapid adhesion to, and enhanced spreading on, laminin isoforms not characteristically resident in the adult corneal basement membrane. This characteristic of human corneal epithelium may explain, at least in part, why amniotic membrane transplantation is proving to be clinically useful for human ocular surface reconstruction.

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There is considerable interest in reducing the volume of gas escaping around the blade tips in a gas turbine by fixing an abrasive, such as c-BN, onto the blade tip with an alloy, such as MCrAlY. Abrasion testing at 1100°C showed that the MCrAlY deformed and the abrasive particles oxidised. The shear stress in the MCrAlY was estimated by finite element methods to be in the range of 5–30 MPa, while measurements of the frictional heating suggest the local temperature is between 1100 and 1200°C. Creep testing showed that conventional MCrAlYs were too weak under these conditions. However, higher strengths were obtained using a continuous reinforcing phase together with NiAl. An Al2O3/ZrO2 abrasive was investigated as a more oxidation resistant abrasive. In this case, reaction with the MCrAlY caused Ni to diffuse into the abrasive forming layers of NiO, weakening the particles and causing premature failure.

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