| 摘要 |
<p>The extremely low temperature cold accumulating material for use in refrigerators, for example, comprises particles containing at least one kind of rare earth element selected from a group consisting of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb. The proportion of particles each having a particle size of 0.01 to 3 mm is 70 % or greater by weight with respect to the whole particles and the proportion of particles each having a shape such that the ratio of the major diameter to the minor diameter is not greater than 5 is 70 % or greater by weight with respect to the whole particles. The particles are manufactured by quenching and solidifying a molten metal containing at least one kind of rear earth element described above. The thus manufacured extremely low temperature cold accumulating material is improved in cold accumulating efficiency and is specifically improved in mechanical strength and in chemical stability.</p> |
