The specific heat under constant pressure, C-p, of intermetallic compounds Hf2Fe, Hf2Co and Hf2Rh with the Ti2Ni structure was obtained by means of differential thermal analysis in the temperature range 275-740 K. The results differ significantly from the Debye theory, even when a correction for optical phonons in Einstein approximation is considered, which indicates existence of a defect contribution to the specific heat. Relative entropy has been determined and the obtained results were fitted and analysed. The anomalous temperature behaviour of C, is discussed, having in mind results of previous investigations of these and similar systems, obtained by other methods.
Note on the Hf-Co phase diagram
作者:K.H.J. Buschow、J.H. Wernick、G.Y. Chin
DOI:10.1016/0022-5088(78)90111-x
日期:1978.5
Hydrogen absorption in various zirconium- and hafnium-based intermetallic compounds
作者:R.M. Van Essen、K.H.J. Buschow
DOI:10.1016/0022-5088(79)90178-4
日期:1979.4
Hydrogen in Ti2Ni-type intermetallic compounds: a proton NMR study
Ni-type compounds Ti 2 NiH 0.61 , Ti 2 CoH 0.56 , Hf 2 FeH 0.59 and Hf 2 CoH 0.71 have been performed over the temperature range 20–424 K and the resonance frequency range 13–90 MHz. The experimental results are analyzed to evaluate the electronic (Korringa) contributions to R 1 and the parameters of hydrogen diffusion. The electronic contribution to the relaxation rate in the Ti-based compounds appears
摘要 Ti 2 Ni 型化合物 Ti 2 NiH 0.61 、Ti 2 CoH 0.56 、Hf 2 FeH 0.59 和 Hf 2 CoH 0.71 的质子自旋-晶格弛豫率 R 1 的核磁共振测量已在 20– 温度范围内进行424 K 和共振频率范围 13–90 MHz。分析实验结果以评估电子(Korringa)对R 1 的贡献和氢扩散参数。Ti 基化合物中电子对弛豫率的贡献似乎远高于 Hf 基化合物。发现氢迁移率以 Ti 2 NiH 0.71 –Ti 2 CoH 0.56 –Hf 2 FeH 0.59 –Hf 2 CoH 0.71 的顺序增加。Hf 2 CoH 0.71 中质子自旋-晶格弛豫率的行为表明至少两个具有不同特征频率的跳跃过程共存。