| 摘要 |
PURPOSE:To improve workability and to reduce a deformed amount in a high temp., by incorporating a specific ratio of lanthanum or a lanthanum oxide into Mo. CONSTITUTION:An ingot to be a starting material in the case of manufacturing a Mo plate is formed by subjecting Mo powder doped with, for example, 0.1-2.0wt% La or the La oxide to hydrogen reduction to execute press sintering; at that time, the crystal of the ingot has a microscopic dope hole contg. a doping agent by an activating effect by the dope of La and the crystal particle becomes to a coarse one. Said ingot is subjected to hot forging or hot working to the thickness direction at >=80% working rate and the doping agent is arranged toward the vertical direction against the plate thickness direction. The pre-coarsened crystal particle becomes to a slenderly grown one, does not become to an isometric fine crystal even if placed in a high temp. state, and furthermore, the growth of the particles toward the plate thickness direction is controlled by the doping agent arranged toward the above-mentioned direction. The Mo plate having the little deformed amount is thus obtd. even placed in the high temp. state.
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