Thermodynamics Prediction of Cerium Inclusions in SS400 Steel and Experiment

• Main Authors: Shuo-YenFang, 方碩彥
• Other Authors: Jyh-Ming Ting
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/zuu6pj

碩士 === 國立成功大學 === 材料科學及工程學系 === 105 === Oxide Metallurgy is a method that could be used to effectively utilize the formation of inclusions to improve the steel quality by pinning grain boundary or forming IAF. Previous studies shows that the deoxidization and desulphurization ability of Ce is higher than Al and Ti, the commercialized deoxidizer,. Therefore, Ce was chosen as the main deoxidizing agent in present research to form the inclusions that could be used to improve the steel quality and to reach the higher cleanliness of steel. In present study, we focus on predicting the inclusion types which could be applied to oxide metallurgy. Wagner’s interaction model (ai = fi * [% i ] ; log fi = ∑_i^j▒〖e_i^j*[ %i ]〗) was applied to build a calculation model to predict the formation of inclusions after the deoxidization and desulphurization process. A thermodynamic prediction module of Ce inclusions was constructed and shows a promising results which is proved by the experiment using Ce as the main deoxidizing agent. The sample was investigated after it was quenched from high temperature. There are three types of inclusion usually formed such as Ce2O2S, Ce2O3, CeAlO3. Furthermore, the size, shape morphology and profound characteristic of each type of inclusion were also studied.