Dispersion of Fine Oxide and Sulfide in Steel Formed by Stable and Metastable Monotectic Reaction

稳定和亚稳偏晶反应形成的钢中细小氧化物和硫化物的弥散

• 批准号: 11450258
• 负责人: ISHIDA Kiyohito
• 金额: $ 9.34万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B).
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11450258/
• 关键词: Sulfide; Morphology; Steel; Phase Diagram; Solubility product; Eutectic reaction; Monotectic reaction; Solidification

The morphology of TiS and CrS in steels formed during solidification and the modification of this morphology by the addition of some alloying elements were investigated by means of optical and scanning electron microscopy. The thermodynamic analyses of phase equilibria of the Fe-Ti-S and Fe-Cr-S ternary systems were also carried out. The results obtained are as follows :1. The morphologies of TiS can be classified into four types ; (i) fine-particle (ii) globular (iii) rod-like and (iv) plate-like sulfides, which depends on the Ti/S ratio and formation process.2. The morphology of TiS in the Fe-0.5%Ti-0.3%S base alloy is the rod-like sulfide while additions of Mn and Zr change the morphology from rod-like to globular. The morphology of sulfide is discussed in terms of eutectic and monotectic-type phase diagrams in the Fe-sulfide quasi-binary system.3. The solubility product of TiS in steel can be determined.log[Ti]γ[S]γ=7.74-17820/T, log[Ti]α, δ[S]α, δ=8.07-17171/Tlog[Ti]liq[S]liq=7.09-12447/T4. The sulfide morphologies in the Fe-Cr-S ternary alloy are calssified into three types ; (i) cell wall (ii) fine particle and (iii) globular sulfides. Fine particle sulfide morphology is the result of the remelting or the eutectioid reaction attendant on the phase transformation of matrix from δ to γ. The morphology of sulfides changes from the cell wall and the fine particle type to the globular type with increasing Cr content.5. Additions of Mn, Ti or Zr to Fe-Cr-S alloys lead to the formation of MnS, TiS or ZrS with the globular, the rod-like and the polyhedral morphologies respectively, which are due to the sulfide formation tendency of the additions and their effect on the nature of the phase diagram.6. The solubility product of CrS in steel at 1%Cr level is determined.log[Cr]liq[S]liq=3.89-4500/T, log[Cr]δ[S]δ=3.35-6550/Tlog[Cr]γ[S]γ=3.43-7307/T, log[Cr]α[S]α=5.32-9068/T

用光学显微镜和扫描电子显微镜研究了钢在凝固过程中形成的TiS和CrS的形态以及通过添加一些合金元素对这种形态的改变。对Fe-Ti-S和Fe-Cr-S三元系的相平衡进行了热力学分析。主要研究结果如下：1. TiS的形貌可分为四种类型：（i）细颗粒（ii）球状（iii）棒状和（iv）板状硫化物，这取决于Ti/S比和形成过程. Fe-0.5%Ti-0.3%S基合金中TiS的形态为棒状硫化物，而Mn和Zr的加入使TiS的形态由棒状变为球状。根据Fe-硫化物准二元系的共晶型相图和单晶型相图讨论了硫化物的形态.测得TiS在钢中的溶度积为log[Ti]γ[S]γ=7.74-17820/T，log[Ti]α，δ[S]α，δ=8.07-17171/Tlog[Ti]liq[S]liq=7.09-12447/T4。Fe-Cr-S三元合金中硫化物的形貌可分为三种类型：（i）胞壁硫化物，（ii）细颗粒硫化物和（iii）球状硫化物。细颗粒硫化物形貌是基体由δ相转变为γ相时发生重熔或类共晶反应的结果。随着Cr含量的增加，硫化物的形貌由胞壁、细颗粒型向球状转变.在Fe-Cr-S合金中添加Mn、Ti或Zr，分别形成了球状、棒状和多面体形貌的MnS、TiS和ZrS，这是由于添加物的硫化物形成倾向及其对相结构的影响.测定了1%Cr钢中CrS的溶度积，log[Cr]liq[S]liq=3.89-4500/T，log[Cr]δ[S]δ=3.35-6550/T，log[Cr]γ[S]γ=3.43-7307/T，log[Cr]α[S]α=5.32-9068/T

项目成果

K.Oikawa: "Morphology Control of MnS Inclusions in Steel during Solidification by the Addition of Ti and Al"Z. Metalkde. 90. 13-18 (1999)

K.Oikawa：“通过添加 Ti 和 Al 来控制凝固过程中钢中 MnS 夹杂物的形态”Z。

K.Ishida: "Phase Equilibria and Microstructural Control of Iron Base Alloys"Computational Material Design, Springer Series. 34. 135-161 (1999)

K.Ishida：“铁基合金的相平衡和微观结构控制”计算材料设计，施普林格系列。

K.Ishida: "Phase Equilibria and Microstructural Control of Iron-base Alloys"In Computational Materials Design, Springer Series in materials Science, Ed.by T.Saito, Springer-Verlag. vol 34. 135-161 (1999)

K.Ishida：计算材料设计中的“铁基合金的相平衡和微观结构控制”，Springer 材料科学系列，T.Saito 编，Springer-Verlag。

K.Oikawa, T.Ikeshoji, H.Mitsui and K.Ishida: "Morphology Control of Sulfide in Fe-Cr-S Alloys during Solidification"Mater.Res.Soc.Symp.Proc.. 580. 369-374 (2000)

K.Oikawa、T.Ikeshoji、H.Mitsui 和 K.Ishida：“凝固过程中 Fe-Cr-S 合金中硫化物的形态控制”Mater.Res.Soc.Symp.Proc.. 580. 369-374 (2000)

K.Oikawa, S.I.Sumi and K.Ishida: "The Effects of Addition of Deoxidation Elements on the Morphology of (Mn, Cr) S Inclusions in Stainless Steels"J.Phase Equilibria. 20. 215-223 (1999)

K.Oikawa、S.I.Sumi 和 K.Ishida：“添加脱氧元素对不锈钢中 (Mn, Cr) S 夹杂物形态的影响”J. 相平衡。