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Crystalline precipitates in a bulk-metallic-glass (BMG) braze were investigated with an intense x-ray microbeam. The precipitates were found in the Pd40Cu30P20Ni10 BMG braze matrix after joining crystalline Ti-6Al-7Nb. However, the role (if any) played by the precipitates in improving the mechanical bond of the BMG/crystalline joint is unknown. X-ray microdiffraction and microfluorescence measurements from small sample volumes were made with an ~ 0.5 x 0.5 μm2 beam. Spatially-resolved Laue diffraction and x-ray fluorescence measurements were made on several second-phase crystals within the BMG matrix. Although precipitate crystals with the observed compositions were anticipated to be predominantly hexagonal, one of the crystals was found to be cubic or tetragonal. The instrumentation includes capabilities for 3D depth-resolved measurements of crystal structure and for fluorescence analysis of elemental composition. Depth profiling gave information about the grain distribution and morphology in the BMG matrix.

Residual strain measurements have been carried out on a fibre reinforced Ti-6Al-4V (Ti-6-4) ring upon fabrication and after machining. As the composite is embedded in Ti-6-4 cladding, neutron diffraction is the only non-destructive technique able to measure residual strains within the composite region. Experimental results indicate that measurements can be made as far as 10 mm below the surface using a large gauge volume and long count times. An axisymmetric finite element model has been constructed, to predict the residual stress state on cooling from consolidation phase and after machining, which incorporates thermal, elastic and creep properties of the constituent materials. Model predictions are in good agreement with experiments.