SAMPE UK & Ireland AGM & Technical Visits

摘要

The SAMPE UK & Ireland Chapter held their Annual General Meeting on Thursday 23rd June 2011, at the Materials Department of U of Loughborough, followed by a technical visit to the nearby facilities of Cobham Composite Technologies. Several of the materials projects at the university were sponsored by or involved companies that are strong supporters of SAMPE. The day began with two fascinating talks on the manufacture and testing of high temperature ceramic composites. The first was by Dr. Andy Leatherbarrow who enthusiastically presented his work on assessment of carbon fibre reinforced silicon carbide (SiC) composites. Several manufacturing methods were discussed as routes to produce SiC, including gas phase chemical infiltration, liquid phase mixing and a hybrid method involving polymer and liquid silicon infiltration into a carbon preform. The SiC samples made from different manufacture processes were assessed for quality with various microscopy techniques, and for material properties using a novel technique called 'Nano Indentation'. This involves a particular 3-sided point used to indent very small zones in the given material and characterise the hardness, Young's Modulus and fracture toughness. The conclusion was that different manufacturing processes can significantly affect the measured properties of the same nominal material (in this case SiC). In the questions that followed, it was clarified that the nano-indentation process can only realistically give a relative measure of properties compared to other samples tested in the same way, and that the results of hardness, toughness etc are not directly comparable to the traditional bulk measurements of hardness, fracture toughness (e.g. data from a Charpy impact test).