We have developed an instrument to study the behavior of the critical current density (Jc) in superconducting wires and tapes as a function of field (μ0H), temperature (T), and axial applied strain (εa). The apparatus is an improvement of similar devices that have been successfully used in our institute for over a decade. It encompasses specific advantages such as a simple sample layout, a well defined and homogeneous strain application, the possibility of investigating large compressive strains and the option of simple temperature variation, while improving the main drawback in our previous systems by increasing the investigated sample length by approximately a factor of 10. The increase in length is achieved via a design change from a straight beam section to an initially curved beam, placed perpendicular to the applied field axis in the limited diameter of a high field magnet bore. This article describes in detail the mechanical design of the device and its calibrations. Additionally initial Jc(εa) data, measured at liquid helium temperature, are presented for a bronze processed and for a powder-in-tube Nb3Sn superconducting wire. Comparisons are made with earlier characterizations, indicating consistent behavior of the instrument. The improved voltage resolution, resulting from the increased sample length, enables Jc determinations at an electric field criterion Ec=10 μV/m, which is substantially lower than a criterion of Ec=100 μV/m which was possible in our previous systems.

The reversible axial strain dependence of the critical current of MgB2 conductors is shown to vary with the temperature and magnetic field. The measured critical temperature and irreversibility field are also found to change reversibly with the axial strain. Combining these effects, we show empirically how the strain dependence of the whole critical surface can be scaled with just three parameters: the strain dependences of its three corner points.

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Abstract-A single-bore 1 meter long 10 T Nb 3 Sn dipole magnet with a 88 mm bore is being developed. Based on powder-in-tube (PIT) Nb 3 Sn strands exhibiting 22 m thick filaments, a Rutherford-type cable with a stainless steel core of 25 micron is employed. All properties relevant for magnet design and operation like critical current, filament magnetization and coupling current control have been investigated experimentally. Their impact on magnet operation is discussed. The effectiveness and reliability of a quench protection system for Nb 3 Sn accelerator magnets relies mainly on the normal zone propagation properties and properly designed and positioned protection heaters. We present measurements and calculations of propagation properties and discuss the consequences for protection heater design.

The X-ray diffraction (XRD) analysis of cement process materials has grown beyond its roots in the laboratory to become an important tool for process control. Combined with its partners, i.e., X-ray fluorescence (XRF) and controlled neutron analysis (CNA), these techniques can provide valuable process control information, i.e., essentially "new eyes", to guide process control decisions. Important developments in XRD analyzers have decreased analysis time from hours to minutes to provide quick results that enable timely process control decisions. XRD phase analysis can provide information to optimize combustion control and mix chemistry, cooler operation, and additive mixtures in finish cement. This paper will provide an overview of all the XRF/XRD applications and then focus on the XRD process control opportunities.Index Terms-Amorphous, cement process control, clinker, neutron analysis, quality assurance, quality control, Rietveld refinement, X-ray diffraction (XRD), X-ray fluorescence (XRF).