Density of high-purity dysprosium in the solid and liquid states

Samples of solid and liquid high-purity dysprosium are exposed to a narrow beam of gamma quanta to measure its density in the temperature range from $293$ to $1912$ K. Volume changes are determined during melting and hcp-bcc structural transformation. The results are compared with the previously obtained data for a technically pure metal. It is shown that, as the purity of metal increases, the range of existence of the bcc phase is narrowed, the melting point and density of the melt increase, and the coefficient of volume expansion of the hcp phase decreases. On the other hand, the impurity composition does not substantially affect the volume changes during phase transformation or the expansion of the bcc phase. Consistent tables of the temperature dependence of the density of dysprosium in the solid and liquid states are developed.