We sought to develop an optimized particle size-dependent separation method to lower the Fe content of pulverized glass-ceramic electric arc furnace (EAF) slag for its improved reclamation as construction materials by considering the structures and the mechanical behavior of the discrete solid phases. After an isothermal crystallization process to enhance the spinel growth, the Vickers hardness and fracture toughness were measured on the spinel and amorphous phases separately from the solidified slag using indentation methods. The characteristic differences in the hardness of the phases were magnified when this glass-ceramic composite was isothermally crystallized. The hardness of the spinel was observed to be lower in slags with higher FetO/Al2O3 mass ratios due to the triclinic unit cell expansion of the spinel, whereas the hardness of the amorphous phase decreased with increasing isothermal period because of the structural transformation into a silicate-dominant network. Fracture toughness could be calculated based on the hardness and crack length, where the Young’s modulus was determined using nanoindentation. The amorphous phase with a lower Fe content and lower fracture toughness resulted in finer powder distribution after pulverization, allowing better separation of the primary crystalline spinel containing higher Fe content from the Fe-deficient amorphous phase according to the particle size.
|Number of pages||10|
|Journal||Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science|
|Publication status||Published - 2017 Feb 1|
Bibliographical noteFunding Information:
This study was supported by the Brain Korea 21 (BK21) Project of the Division of Humantronics Information Materials grant no. 2014-11-0010 and the Ministry of Trade, Industry and Energy grant no. 10054806.
© 2016, The Minerals, Metals & Materials Society and ASM International.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Mechanics of Materials
- Metals and Alloys