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A study of the strain effect and martensitic transformation of multifilamentary Nb(sub 3)Sn wires reveals that Ti addition to the wire represses martensitic transformation. Elastic modulus variation in these wires induces the martensitic transformation to contribute to residual strain. Ti-added Nb(sub 3)Sn superconducting wires provide information on high-field superconducting magnets.

Magnetocaloric and related properties of Ru and Ni substituted (MnFe)2(PSi) are presented. It is found that Ru and Ni are effective doping elements to reduce the thermal hysteresis of (MnFe)2(PSi). The origin of the thermal hysteresis is discussed on the basis of a thermodynamic model. It is shown that the elastic energy is responsible for the thermal hysteresis. We also show recent developments of the production process of Mn compounds in an industrial scale. [ABSTRACT FROM AUTHOR]

To observe nonlinearity in the stopping power of a nonideal plasma for heavy ions, we are planning a beam-plasma interaction experiment using 10-100 keV/u projectiles. For the interaction experiment, a nonideal hydrogen plasma target was developed by means of a shock technique. Time-resolved spectroscopic measurements determined the temporal evolution of the electron density and temperature of the shock plasma. These data revealed that the structure behind the shock front has an appropriate spatial and temporal distribution to be used as a target. We also evaluated the temporal evolution of the Coulomb coupling constant and the degree of ionization at a fixed position where the projectiles are injected. We discuss the feasibility of the nonlinear stopping experiment by evaluating the beam-plasma coupling constant expected from the measured plasma parameters. [ABSTRACT FROM AUTHOR]

We measured directly by neutron diffraction the axial and lateral residual strains for the prebent and the as-reacted CuNb/Nb3Sn wires at room temperature and at 7 K, in order to investigate the change of the residual strain with prebending treatment. In the axial direction of the wire, the residual strain was changed with 0.20% to the tensile side when measured at both temperatures, while in the lateral direction, the change was 0.08% and 0.03% to the compressive side for the measurements at RT and 7 K, respectively. From the obtained data, we estimated the deviatoric strain. At 7 K, the value is 0.40% for the as-reacted wires and it reduces to 0.19% when the prebending is applied with a strain [variant_greek_epsilon]pb=0.8%. These results suggest that the reduction of the residual strain in the axial direction as well as in the lateral direction, i.e., of the deviatoric strain is responsible for the observed enhancement in the superconducting properties of the prebent Nb3Sn wires. In addition, we succeeded in the quantitative evaluation of the deviatoric strain dependence of the upper critical field for the practical Nb3Sn wire. This is very important for the understanding of the general axial strain dependence of the superconducting properties. [ABSTRACT FROM AUTHOR]

Neutron diffraction is used for measuring the axial and lateral residual strains for the prebent and the as-reacted CuNb[Nb.sub.3]Sn wires at room temperature in order to investigate the change of the residual strain with prebending treatment. The results have indicated that the reduction of the residual strain in the axial direction as well as in the lateral direction is responsible for the enhancement in the superconducting properties of the prebent [Nb.sub.3]Sn wires.

Presents a study which clarified the relationship between the martensitic transformation and the strain effect in bronze-processed multifilamentary Nb[sub3]Sn superconducting wires. Details of the strain effects on critical current density for pure Nb[sub3]Sn and titanium-added (Nb, Ti)[sub3]Sn wires; Details of the experiment; Calculation of the residual strain in bronze-processed multifilamentary Nb[sub3]Sn superconducting wires.

Investigates the influence of fast neutron irradiation on critical current and its strain dependence in a bronze processed fine multifilamentary Nb[sub3]Sn superconducting composite. List of the specification of the bronze processed fine multifilamentary Nb[sub3]Sn superconducting composite wire specimen; Summary of material parameters of the multifilamentary Nb[sub3]Sn.