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The neutron detector of Necsa's "Powder Instrument for Transition in Structure Investigations" (PITSI) diffractometer is a pseudo area configuration that has an active area of ∼ 610 × 375 mm 2 that is established by 15 vertically stacked 3 He gas-filled linear position sensitive tube detectors. In its standard geometry the sample-to-detector distance is 1.6 m that gives a detector sustention angle of 2θ = 21 •. A full diffraction pattern over the range 10 • 2θ 115 • is covered in six discrete steps. This process may be very time consuming for weak scattering materials. To improve the instrument performance, the active area of the detector bank is being increased to 48 tubes comprising three banks each with 16 tubes separated by a dead-space of 18.5°at 1.6 m. This configuration requires a step-scan of only 2 positions to cover the complete 2θ range of interest, effectively increasing the instrument acquisition speed by a factor greater than 3. As an added flexibility the overall data acquisition time can be further reduced by decreasing the sample to detector distance to 1.2 m that increases the intensity per pixel at the expense of the instrument's angular resolution. In this report the conversion of the current USB-communication based system to an Ethernet based system to reduce the hardware footprint and complexity, as well as the amount of cabling needed is reported. The optimisation of the operating parameters of the new detector electronics is also discussed.

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This paper presents the results of eigenstrain analysis in non-uniformly shaped shot-peened 17-4PH stainless steel samples. The finite element models are established for inverse eigenstrain analysis of slices and bulk conical samples. It is shown that the elastic strain distributions and relief are directly related to peening intensity and sample shape/thickness via the underlying permanent strain, or eigenstrain. Thus, the effect of the peening treatment is best described in terms of the induced eigenstrain. The proposed framework for predictive modelling of residual stresses in non-uniformly shaped shot-peened materials allows efficient reconstruction of complete residual stress state, and provides an excellent basis for developing predictive tools for in service performance and design optimization.