Abstract
Inclusion species formed in SS400 steel with Ce-addition was predicted by thermodynamic calculation. The analysis of the inclusion morphology and size distribution was carried out by applying Scanning Electron Microscopy (SEM) and Transmission Electron Microscope (TEM). Nano-Fe3O4 particles were also found in cerium-deoxidized and -desulfurized steel and their shapes were nearly spherical. The complex Ce2O3 inclusions covering a layer of 218 nm composed by several MnS particles with similar diffraction pattern. Most importantly, the complex Ce2O3 characterized by using TEM diffraction is amorphous in the steel, indicating that Ce2O3 formed in the liquid iron and then MnS segregated cling to it.
Highlights
Nonmetallic inclusions with high melting point in steel could be harmful in production of high grade wire, spring, and bearing steels[1, 2]
This paper focuses on (1) verifying the thermodynamic calculations for main inclusions formed at high temperature and room temperature in SS400 steel; (2) the morphologies of inclusions formed during furnace-cooling; 1Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan. 2Physics Department, Technische Universität München, Munich, 85748, Germany. 3Physics Department, LudwigMaximilians-Universität München, Munich, 80799, Germany. 4Department of Electronic Engineering, Kao Yuan University, Kaohsiung, 82151, Taiwan. 5Steelmaking Process Development Section, China Steel Corporation, Kaohsiung, 81233, Taiwan
Based on the calculation of the solidification temperature, it was obviously found that the liquid steel would completely solidify below 1770 K
Summary
Nonmetallic inclusions with high melting point in steel could be harmful in production of high grade wire, spring, and bearing steels[1, 2]. A typical rare earth element, has been used as an important deoxidizer in many steels to improve mechanical properties by grain refinement[2]. CeS particles with a fine distribution in steel would shift the process of nucleation from austenite grain boundaries to intra-granular sites when transforming from austenite to ferrite[21]. This process has been studies extensively in low alloy steel weld metals studying the contribution of sulfide and oxide inclusion to acicular ferrite formation[22, 23]. What’s more, a model for inclusion sizes distribution is established for SS400 steel with cerium addition
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
