Small-angle neutron scattering of alkali metals at moderate uniaxial pressure and low temperature

Autor(en)

Maciej Krystian, Manfred Prem, Wolfgang Pichl, Gerhard Krexner

Abstrakt

This paper reports on the development of a cryostat for neutron small-angle scattering experiments on alkali metals under uniaxial compression in a temperature range from 5 K to room temperature. The investigation was motivated by earlier observations of 'premartensitic' anomalies in metallic lithium and potassium which seem to suggest that nuclei of a low-temperature phase might be generated in the undercooled bcc structure either by cooling alone or by additional mechanical deformation. Cooling to 120 K in lithium and to 5 K in potassium, respectively, without applied load produced only very slight changes in the SANS patterns. However, after uniaxial compression of 3% at these temperatures anisotropic scattering patterns developed, suggesting the formation of small particles embedded in the bcc matrix whose orientation is related to the deformation direction. Π2005 IOP Publishing Ltd.

Organisation(en)

Physik Funktioneller Materialien

Seiten

3173-3178

Anzahl der Seiten

6

DOI

https://doi.org/10.1088/0953-8984/17/40/021

Publikationsdatum

2005

ÖFOS 2012

103015 Kondensierte Materie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/433ca2d4-6fc8-4a57-8801-eb68b9ac2f53