Development at temperature mrasurment system and solidification microstructure control under rapid solidification condition

温度测量系统开发及快速凝固条件下凝固组织控制

• 批准号: 05452298
• 负责人: UMEDA Takateru
• 金额: $ 4.29万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05452298/
• 关键词: rapid solidification; phase selection; rapidly solidified powders; modeling; Nd-Fe-B magets; デンドライト成長; 熱デンドライト; Nd-Fe-B; 光温度計測; 形態選択; 18-8ステンレス鋼; 準安定γ相

Rapid solidification processing is expected to develop new near net shape methods and to bring out new functional properties by making fine structures, supersaturation, metastableand amorphous phases. To develop further rapid solidification processing, it is necessary to under stand deeply rapid solidification phenomenaby introducing appropriate measuring methods and also to simulate phenomena. This research is aimed 1) to predict quantitatively morphology and phase selection, and segregation, 2) to make clear a guide line to develop the rapid solidification processing of structural and also magnetic materials. Results obtained are as follows ;1) Morphology and phase selection are established, especially for alloys with peretectic reactions.2) Solidification of rapidly solidified powders is simulated under the conditions of undercooling, diameter of powders and heat transfer between ambientgas and powders.3) Crystal growth model is developed by incorporating empirical nucleationequations occurred between in got and mold surfaces.4) Phase selection is modeled for Nd-Fe-B magnets. The condition of producing primary phase Nd_2Fe_<14>B is established controlling solidification rate and initial composition.5) Solidfication path is established for Nd-Fe-B magnets. The amount of Nd_2Fe_<14>B and boundary phases can be predicted.

快速凝固工艺有望发展新的近净成形方法，通过产生细小的组织、过饱和相、亚稳相和非晶相来产生新的功能性能。为了进一步发展快速凝固工艺，有必要通过引入合适的测量方法来深入了解快速凝固现象，并对现象进行模拟。本研究的目的是：1)定量预测组织形态、相选择和偏析；2)明确发展结构材料和磁性材料快速凝固工艺的指导思想。研究结果如下：1)建立了快速凝固粉末的微观形态和相选择模型，特别是对于具有过冷反应的合金。2)模拟了过冷度、粉末直径和气氛气体与粉末之间的热传递条件下快速凝固粉末的凝固过程。3)结合GET和结晶器表面之间的经验成核方程，建立了晶体生长模型。4)建立了NdFeB磁体的相选择模型。通过对凝固速度和初始成分的控制，确定了初生相Nd2Fe&lt；14&Gt；B的生成条件。5)确定了Nd2FeB磁体的凝固路径。可以预测Nd2Fe&Lt；14&Gt；B和晶界相的数量。

项目成果

梅田 高照: "凝固現象の基礎" 社団法人 日本鉄鋼協会, 294 (1994)

Takateru Umeda：“凝固现象的基础”日本钢铁研究所，294 (1994)

S.G.Kim: "Microstructural evolution in a rapidly solidified Al-4mass%Fe droplet" Materials Science and Engineering. A181/A182. 1156-1160 (1994)

S.G.Kim：“快速凝固的 Al-4mass 液滴中的微观结构演化”材料科学与工程。

梅田 高照: "包晶反応を有する合金の晶出相に及ぼす凝固速度の影響" 材料とプロセス No.1. 7. (1994)

Takateru Umeda：“凝固速率对包晶反应合金结晶相的影响”Materials and Processes No. 1. 7. (1994)

W.Kurz: "Phase and Microstructure Selection During Growth of Peritectic Systems" Proc.Japan-US Seminar on Solidification Processing for the 21st Century. 1-11 (1994)

W.Kurz：“包晶系统生长过程中的相和微观结构选择”Proc.日美21世纪凝固加工研讨会。

T.Umeda: "Fundamentals of Solidification in Slab Casting" The 153 154th Nishiyama Memorial Seminar. 45-88 (1994)

T.Umeda：“板坯铸造凝固基础”第153-154届西山纪念研讨会。