Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Engineering / Faculty of Engineering >
Peer-reviewed Journal Articles, etc >
In-situ Study of Crystallisation Behaviour of CaO–SiO2–Na2O–B2O3–TiO2–Al2O3–MgO–Li2O Fluorine-free Mould Fluxes with Different CaO/SiO2 Ratios
Title: | In-situ Study of Crystallisation Behaviour of CaO–SiO2–Na2O–B2O3–TiO2–Al2O3–MgO–Li2O Fluorine-free Mould Fluxes with Different CaO/SiO2 Ratios |
Authors: | Yang, Jian Browse this author | Zhang, Jianqiang Browse this author | Sasaki, Yasushi Browse this author | Ostrovski, Oleg Browse this author | Zhang, Chen Browse this author | Cai, Dexiang Browse this author | Kashiwaya, Yoshiaki Browse this author →KAKEN DB |
Keywords: | fluorine-free mould fluxed | crystallisation behaviour | CaO/SiO2 mass ratio | hot termocouple technique |
Issue Date: | 15-Apr-2016 |
Publisher: | Iron and Steel Institute of Japan |
Journal Title: | ISIJ International |
Volume: | 56 |
Issue: | 4 |
Start Page: | 574 |
End Page: | 583 |
Publisher DOI: | 10.2355/isijinternational.ISIJINT-2015-583 |
Abstract: | The increasing environmental concern for the fluorine emission in steel continuous casting makes the development of fluorine-free mould fluxes imperative. The main challenge in the development of fluorine-free mould fluxes is controlling heat transfer rate which is closely related to the crystallisation behaviour of mould fluxes. In this study, the crystallisation behaviour of CaO–SiO2–Na2O–B2O3–TiO2–Al2O3–MgO–Li2O fluorine-free mould fluxes with CaO/SiO2 mass ratios from 0.9 to 1.2 was examined using single hot thermocouple technique (SHTT) and double hot thermocouple technique (DHTT). Continuous cooling transformation (CCT) and time-temperature transformation (TTT) diagrams developed using SHTT showed that the crystallisation temperature increased and the incubation time decreased with the increase of CaO/SiO2 ratio. DHTT was used to simulate the temperature gradient between copper mould and strand in steel continuous casting. Analysis of the crystallinity evolution in the simulated temperature field showed an increased crystallinity of fluxes with the increase of the CaO/SiO2 ratio at certain times. The crystal phases and crystal morphologies formed in different conditions were analysed by X-ray diffraction (XRD), scanning electron microscope (SEM), and X-ray energy dispersive spectroscopy (EDS). Phases formed in the process of the flux crystallisation included CaSiO3, Ca2MgSi2O7 and Ca11Si4B2O22. It revealed that CaSiO3 was the major phase at low CaO/SiO2 ratio. The amount of Ca2MgSi2O7 and Ca11Si4B2O22 increased with increasing CaO/SiO2 ratio. |
Rights: | 著作権は日本鉄鋼協会にある |
Type: | article |
URI: | http://hdl.handle.net/2115/75674 |
Appears in Collections: | 工学院・工学研究院 (Graduate School of Engineering / Faculty of Engineering) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
|
Submitter: 柏谷 悦章
|