Growth of large single crystals of Heusler alloys, Ni2MnSn and Ni2Mn1−xVxSn, for neutron inelastic scattering experiments

Large single crystals up to 15 mm by 28 mm of the Heusler alloys Ni2MnSn and Ni2Mn0·8V0·2Sn have been grown using Czochralski and Kyropoulous (top-seeding) techniques. Good crystals could be obtained from high purity alumina crucibles or from a water-cooled cold crucible (Hukin-type) using pulling rates from 20 to 25 mm/h or cooling rates of about 10°C/h. Examination of the best as grown boules by Laue photography and neutron diffraction showed the presence of a single crystal or one major grain plus a minor grain miroriented by less than 1°. Such crystals are suitable for neutron inelastic scattering experiments.