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We have measured the thermo-electric properties of the vanadium substituted Ti(1-x)VxNiSn samples with x = 0.01, 0.02, 0.05, 0.1 and 0.2 from 2 K to 390 K. Electrical conductivity, thermal conductivity and Seebeck coefficient were measured in the above temperature range and the thermo-electric figure of merit (ZT) was estimated. We have observed that the ZT increases from 0.11 in the parent TiNiSn to 0.18 in the T0.9V0.1NiSn sample at 390 K. Photo electron spectroscopy results indicates that the enhancement of ZT is associated with the increase in the density of states at the Fermi level because of vanadium substitution at the Ti sites.

We report here the structural, electrical, thermal, and magnetic properties of the as-cast V 1 − xZr x alloys ( x = 0–0.4) at low temperatures. We observe that all the alloys undergo successive peritectic and eutectic reactions during cooling from the melt, which leads to the formation of five phases, namely, a body centered cubic β-V phase, two phases with slightly different compositions having a face centered cubic ZrV 2 structure, a hexagonal closed packed α-Zr phase, and the β-Zr precipitates. The amount of each phase is found to be dependent on the concentration of zirconium in vanadium. The β-V and ZrV 2 phases show superconductivity below 5.2 K and 8.5 K, respectively. We show that the critical current density is large for the V-rich V 1 − xZr x alloys with x > 0.1. The grain boundaries generated from the eutectic reaction and the point defects formed due to the variation in the composition are found to be responsible for the pinning of flux lines in low and high magnetic fields, respectively. Our studies reveal that the choice of the composition and the heat treatment, which leads to eutectic reactions are important in improving the critical current density in this alloy system.

Ion irradiation plays an important role to tailor the microcrystalline structure and the corresponding magnetic anisotropy by high local energy deposition and defect accumulation. In the present work, we have investigated the effects of nuclear energy loss and electronic energy loss on the phase transformation and magnetic anisotropy of thin polycrystalline Co films. As-deposited film shows polycrystalline behavior with twofold uniaxial magnetic anisotropy, characteristic to hcp-Co film. 320 keV Au ions induce phase transformation from hcp to fcc. Similar phase transformation have been observed in the case of film irradiated by 120 MeV Au ions. Rate of phase transformation is discussed in terms of electronic and nuclear energy losses and the corresponding changes in the magnetic anisotropic behavior are discussed in the light of uniaxial and fourfold magnetic anisotropy.