We present a rheometer that combines the possibility to perform in-situ X-ray experiments with a precise and locally controlled uniaxial extensional flow. It thus allows to study the crystallization kinetics and morphology evolution combined with the rheological response to the applied flow field. A constant uniaxial deformation rate is ensured thanks to a fast control scheme that drives the simultaneous movement of the top and bottom plate during a pulling experiment. A laser micrometer measures the time evolution of the smallest diameter, where the highest stress is concentrated. The rheometer has a copper temperature-controlled oven with the ability to reach 250 • C and a N 2 connection to create an inert atmosphere during the experiments. The innovation of our rheometer is the fixed location of the midfilament position, which is possible because of the simultaneous movement of the two end plates. The copper oven has been constructed with four ad-hoc windows: two glass windows for laser access and two kapton windows for X-ray access.The key feature is the ability to perfectly align the midfilament of the sample to the laser micrometer and to the incoming X-ray beam in a synchrotron radiation facility, allowing to investigate structure and morphologies developed during extensional flow. The rheological response measured with our rheometer for LDPE is in agreement with the linear viscoelastic envelope and with the results obtained from existing extensional rheometers.To demonstrate the capability of the instrument we have performed in-situ time-resolved X-ray experiments on LDPE samples exhibiting extensional flow-induced crystallization.

While the industrial interest in sheet metal with improved specific-properties led to the design of new alloys with complex microstructures, predicting their safe forming limits and understanding their microstructural deformation mechanisms remain as significant challenges largely due to the inadequacy of the existing experimental tools. The investigation of the strain-path dependent failure mechanisms requires miniaturized testing equipment, which can be placed in a scanning electron microscope for in situ experiments. So far, such tests could only be carried out for a single strain path (uniaxial tension). In this work, in order to fill this gap, a miniaturized Marciniak test setup is designed, built and tested. With this setup real-time, multi-axial tests of industrial sheet metal can be carried out to the point of fracture within a

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The goal of the present study was to develop and evaluate an isometric dynamometer for measuring mouse ankle flexor torque after electric stimulation of the nerve. The dynamometer was to be used within an magnetic resonance (MR) apparatus and should require minimal surgical intervention. To quantify the effect of the magnetic field on contractile parameters, measurements were performed both outside and inside the MR apparatus. The effect of magnetic field gradient switching that accompanies rapid MR scanning was tested also. The set-up required no surgical intervention except for chronic implantation of an electrode. The dynamometer has a high mechanical frequency response (270 Hz). Measured muscle strengths were identical outside and inside the MR scanner. However, during fast magnetic field gradient switching, the variability increased and the measured strength decreased slightly (7%). The noise level of the dynamometer (0.02-0.03 N.mm) was low compared with the strength of the dorsal flexors (2 N.mm). Fast gradient switching increased the noise level (0.07 N.mm). The dynamometer had no observable adverse effects on the quality of the MR images of the mouse hind limb. We conclude that the dynamometer enables accurate measurements of mechanical muscle performance during exercise protocols within an MR apparatus under physiological conditions.