TiC,HfC分散強化型Mo合金板の結晶粒成長および焼鈍集合組織

抄録

In order to understand in detail the secondary recrystallization behavior of fine-grained molybdenum alloy sheets dispersed with TiC and HfC particles of 0.8mol%, the effects of kinds of dispersed particle on the secondary grain growth behavior and annealing textures in hot-rolled dispersion strengthened molybdenum sheets were investigated. First, it was recognized that dispersed particles, which are present in the form of Ti (O_x, C) and Hf (O_x, C) as complicated oxides and carbides at the primary recrystallized grain boundaries, play an important role as inhibitors to the normal grain growth and conversely as promoters of the abnormal grain growth at higher temperatures in both molybdenum alloy sheets. Moreover, the temperature at which secondary recrystallization commences from both molybdenum alloy sheets is strongly dependent on the kinds of dispersed particle and is correspondent to their dissociation and dissolution. Secondary, it was found that most components of secondary textures correspond to very weak components in the primary recrystallization textures and are related by a rotation of approximately 20°-30° about the <110> axis of the strong primary recrystallized {111} (<112>+<110>) matrice in both molybdenum alloy sheets.