Effect of hydrogen on the temperature dependence of the elastic constants of vanadium single crystals
作者:
C. R. Ko,
K. Salama,
J. M. Roberts,
期刊:
Journal of Applied Physics
(AIP Available online 1980)
卷期:
Volume 51,
issue 2
页码: 1014-1021
ISSN:0021-8979
年代: 1980
DOI:10.1063/1.327729
出版商: AIP
数据来源: AIP
摘要:
The changes in the absolute values of the elastic constantsC′,CLandC44by the ultrasonic technique over the temperature range 144–320 K with varying amounts of hydrogen in Vanadium up to 1.5 at.% have been determined. In the &agr; phase, the changes in the absolute values ofC′ andCLwere found to be linear with negative slopes of 2.0% and 0.5%/at.% H, respectively. The changes inC44in the &agr; phase varied between 0 and 0.5 or 0.9% H. The bulk modulus and Voight‐Reuss average Young’s modulus in that phase were found to decrease 0.70% and 0.65%/at.% H, respectively. The elastic constants in the temperature range of the &agr; phase exhibited no change in their temperature dependences by the addition of hydrogen. The present results are compared to the results of other published investigations. The anharmonic effects are discussed in the light of the volume expansion due to H in V upon the elastic constants, the possible electronic effect by suggesting the addition of H to V is analogously similar electronically to adding Cr to V and finally the Snoek relaxation effect. It is concluded that the Snoek relaxation best describes the &Dgr;C′ effect observed when hydrogen is present in the &agr; phase. This effect yields an asymmetric distortion energy parameter [3(A−B)/(A+2B)] of the order of 0.47.
点击下载:
PDF
(570KB)
返 回