Control of Transformation Microstructure in Steel by use of Inclusions

利用夹杂物控制钢中的相变显微组织

• 批准号: 08555163
• 负责人: MAKI Tadashi
• 金额: $ 7.81万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08555163/
• 关键词: Steel; austenite; ferrite; pearlite; crystallography; inclusion; precipitation; interphase boundary; 鉄合金; 相変態; 速度論; 異相界面; パ-ライト; 粒内フェライト変態

Proeutectoid ferrite (bcc α) nucleation on the Bl (NaCl)-type complex inclusions/precipitates (e.g. oxide, sulfide, carbide, nitride) dispersed in austenite (fcc γ), denoted as intragranular ferrite transformation, has been used to refine the microstructure in the heat affected zone to improve the toughness of low and medium carbon steels. The present study aims to study the ability of various complex inclusions/precipitates (MnS, MnS+VC, MnS+V(C,N)) in austenite as nucleation sites in proeutectoid ferrite transformations by electron microscopy.In the presence of MnS+V(C,N) complex precipitates, intragranular ferrite nucleation is markedly accelerated. V(C,N), which usually holds a cube-cube orientation relationship (<001>ィイD2γィエD2//<001>ィイD2vcィエD2) when they forms within austenite grains, does not exhibit any specific orientation relationship with respect to austenite matrix when they nucleate on incoherent MnS. Many of intragranular ferrite crystals apparently do not hold a specific orientation relationship with V(C,N) and austenite. These crystallographic analyses revealed that the randomization in the matrix/precipitate orientation relationships occurs in the precipitation at incoherent interphase boundaries.

先共析铁素体（bcc α）在分散于奥氏体（fcc γ）中的B1（NaCl）型复合夹杂物/析出物（如氧化物、硫化物、碳化物、氮化物）上形核，称为晶内铁素体相变，可细化热影响区组织，提高低、中碳钢的韧性。利用电子显微镜研究了奥氏体中MnS、MnS+VC、MnS+V（C，N）复合夹杂物/析出物作为先共析铁素体形核中心的能力，MnS+V（C，N）复合析出物的存在显著促进了晶内铁素体形核。V（C，N）在奥氏体晶粒内形成时通常具有立方-立方取向关系（<001>立方D2γ立方D2//立方<001>D2 vc立方D2），但在非共格MnS上形核时，相对于奥氏体基体不表现出任何特定的取向关系。许多晶内铁素体晶体与V（C，N）和奥氏体没有特定的取向关系。这些晶体学分析表明，在基体/沉淀物取向关系的随机化发生在不相干的相间边界的沉淀。

项目成果

T. Furuhara, T. Maki: "Crystallography and Interphase Boundary Structure of B1-type Carbides in Austenite"Materia Japan. 27. 366-366 (1998)

T. Furuhara、T. Maki：“奥氏体中 B1 型碳化物的晶体学和相间边界结构”Materia Japan。

K. Oichi, T. Furuhara, T. Maki: "Interphase Boundary Structure of Grain Boundary Precipitate in aNc-Cr Alloy"Proc of PTM'99. 1. 573-576 (1999)

K. Oichi、T. Furuhara、T. Maki：“aNc-Cr 合金中晶界沉淀的相界结构”Proc of PTM99。

古原 忠: "オーステナイトより析出したBI型炭化物の結晶学および異相界面構造"まてりあ. 27. 366-366 (1998)

Tadashi Furuhara：“奥氏体沉淀的 BI 型碳化物的晶体学和异相界面结构”Materia 27. 366-366 (1998)。

T.Maki: "Interphase bormdary structure of grain bormdary precipitate in a Ni-Cr allors"Proc of PTM'99. 1. 573-576 (1999)

T.Maki：“Ni-Cr allors 中晶粒硼沉淀物的界面硼结构”Proc of PTM99。

T.Furn kara: "Crgptallography and Interphase Boundary Structure of B1-type Precipitate in Austenite" Interface Science and Materials Interconnection. 363-366 (1996)

T.Furn kara：“奥氏体中B1型沉淀物的Crgptallography和相间边界结构”界面科学与材料互连。