著者

千早 正 塩田 信雄 小野崎 長英

出版者

社団法人 日本金属学会

雑誌

日本金屬學會誌.B (ISSN:03694615)

巻号頁・発行日

vol.14, no.7, pp.43-45, 1950

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In this report, a research has been made concerning the change of the hardness and the crystal growth of Se in accordance with the time of heat treatments by means of the Marten&rsquo;s scratch hardness tester and of the X-ray method, respectively. And we measured the surface tension in the melting state at each temperatures with the dropping method.<BR>As was shown in Fig. 1, the Marten&rsquo;s hardness diminished rapidly in 5 minutes, and then after 20 minutes, it began to increase until 4 hours had elapsed. This tendncy was almost opposite to that of the impact value.<BR>By the X-ray method, we found that, in the first stage of the treatment, the crystal had some preferred orientation (see Fig. 2-a), and the internal strain (Fig. 3-a). And then in the second stage the strain disappeared (Fig. 3-b), the crystals showing a random orientation and a grain growth (Fig. 2-b) as well.<BR>When the Debye-Scherrer&rsquo;s method was applied in the first stage of the treatment, the lattice constant of <I>a</I>-axis expanded and that of <I>c</I>-axis contracted as compared with those in the normal state (see Table 1).<BR>When we measured the surface tension,it satisfied the E&ouml;tvos empirical relation up to 300&deg;, while it decreased rapidly around 320&deg; and then gradually diminished (Fig. 5).