STRAIN ENHANCED GROWTH OF PRECIPITATES CONTRIBUTING TO THE SUBSTRUCTURE STABILITY OF HIGH STRENGTH HEAT RESISTANT MATERIALS

应变增强的析出物生长有助于高强度耐热材料的组织稳定性

• 批准号: 13650755
• 负责人: ENDO Takao
• 金额: $ 2.3万
• 依托单位: YOKOHAMA NATIONAL UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13650755/
• 关键词: creep; high temperature; subgrain; Ostwald ripening; precipitate; solute dragging; threshold stress; scavenging effect; スキャンベンジング効果; 耐熱鋼; 下部組織; クリープ寿命

Advanced heat resistant steels usually contain fine subgrains and densely populated dislocations, which are both introduced during martensitic transformation. Their excellent high temperature strength is ascribable mainly to the substructure and precipitation strengthening. It is important to note that the thermal stability of substructure is controlled by the coarsening rate of precipitates which can retard the dislocation motion and the migration of subboudaries. A recent study on T91 suggests that the rate of coarsening is dependent on creep strain. The present study was undertaken to examine whether or not the coarsening rate of precipitates is strain dependent, and what mechanisms is likely to occur. Within the project term, three items were examined ; (1) analysis of existing data on T91, (2) experimental study and analysis on Al-Cu and magnesium alloys, and (3) numerical simulation of dislocation motion with solute atmosphere. From the studies on Al-Cu and magnesium alloys, confirmation was made that the coarsening rate of precipitates was strain dependent, and the effect of strain on coarsening became gentle when strain rates were higher. Based on the assumption that the dislocation motion with solute atmosphere enhanced the solute transport and lead to the enhancement of coarsening rate, a model was proposed. The model explained the experimental results satisfactorily.

晚期耐热钢通常包含细胞晶粒和人口稠密的脱位，这两者都在马塞西氏菌转化过程中引入。它们的出色高温强度主要可归因于下部结构和降水加强。重要的是要注意，子结构的热稳定性受到可以阻止位错运动和子凸的迁移的沉淀速率控制的。对T91的最新研究表明，变高的速度取决于蠕变菌株。进行本研究是为了检查降水量的变质速率是否取决于应变，以及可能发生哪些机制。在项目术语中，检查了三个项目； （1）对T91，（2）对Al-Cu和镁合金的实验研究和分析的现有数据的分析，以及（3）用溶质大气对位错运动的数值模拟。从对Al-Cu和镁合金的研究中，可以证实沉淀的变厚速率取决于应变，并且在应变速率较高时，应变对变高的影响变得温和。基于以下假设：溶质大气的脱位运动增强了溶质的传输并导致更高的速率提高，提出了一个模型。该模型令人满意地解释了实验结果。

项目成果

T.Nakajima, M.Takeda, T.Endo: "EFFECT OF CREEP STRAIN ON THE PRECIPITATE COARSENING OF A MAGNESIUM ALLOY, AZ8O"Proceedings of PLASTICITY 2003, Quebec City. (2003)

T.Nakajima、M.Takeda、T.Endo：“蠕变应变对镁合金 AZ8O 沉淀粗化的影响”2003 年塑料学报，魁北克市。

Takao Endo: "Relation among Hardness, Structure and Long-Term Creep Behavior of Mod.9Cr.-1 Mo Steel"Proceedings of the 202 Korea-Japan Joint Symposium on Advanced Engineering and Science.

Takao Endo：“Mod.9Cr.-1 Mo钢的硬度、结构和长期蠕变行为的关系”第202届韩日先进工程与科学联合研讨会论文集。

遠藤孝雄, 増山不二光, 朴 奎侠: "改良9Cr-1Mo鋼のクリープ変形に伴う硬度と下部組織の変化"鉄と鋼. 88. 526-533 (2002)

Takao Endo、Fujimitsu Masuyama、Kyu-hye Park：“改性 9Cr-1Mo 钢蠕变变形导致的硬度和亚结构变化”Tetsu to Hagane 88. 526-533 (2002)。

Kyu Seop Park, Takao Endo: "Relation among Hardness, Structure and Long-Term Creep Behavior of Mod.9Cr.-1Mo Steel""Advanced Studies in mechanical Engineering" Ed. By Hae-Ho Joo et al.. 49-52 (2002)

Kyu Seop Park、Takao Endo：“Mod.9Cr.-1Mo 钢的硬度、结构和长期蠕变行为之间的关系”“机械工程高级研究”编辑。

T.Nakajima, M.Takeda, T.Endo: "EFFECT OF CREEP STRAIN ON THE PRECIPITATE COARSENING OF A MAGNESIUM ALLOY, AZ80"Proceedings of PLASTICITY 2003, Quebec City. (2003)

T.Nakajima、M.Takeda、T.Endo：“蠕变应变对镁合金 AZ80 沉淀粗化的影响”2003 年塑料学报，魁北克市。