Characterization and three-dimensional reconstruction of pores of self-reducing pellets done by EAF dust

Abstract

This work focused on the characterization physical and microstructural of the self-reducing pellet made of Electric Arc Furnace (EAF) dust using different low cost techniques. The serial sectioning technique was used to evaluate detailed measurements of pore connections, tortuositiy of pores and porosity distribution. The chemical analysis using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICPAES), Scanning Electron Microscopy (SEM), Optical Microscopy (OM) and X-ray diffraction were carried out to identify the common phases presented in EAF dust agglomerate. It was observed that the pellet phase composition is formed by iron as magnetite, metallic iron, wustite, and zinc ferrite. The visualization of the reconstructed 3D microstructure provided average qualitative and quantitative analysis of the porosity (41.61%), a consistent result and in accordance with that obtained by pycnometry technique (41.53%). As expected, these results are more precise when compared with the result obtained by two-dimensional technique (23.41%). In addition, it was calculated the value of the tortuosity parameter (0.84) that suggested a morphological structure closest to cylindrical shape.

Study on Effect of EAFD Particulate Reinforcement in AA7075 Aluminum Matrix Composites

“…The type of scrap metal melted inside the electric arc furnace (EAF) determines the chemical composition of the dust, which is defined as a rich material in ferrous or nonferrous metal. EAFD is composed of iron and zinc oxide, which is volatilized, and also calcium, chromium, magnesium, sílica and, other toxic compounds as lead and cadmium 2,3,4,5 .…”

Three-Dimensional Microstructure Reconstruction and Phase Boundary by Serial Sectioning and Numerical Approach

“…The wear and corrosion resistance of powder metallurgy stainless steel parts have been improved by modifying the process parameters [4][5][6][7]. The wear mechanism of powder metallurgy 316L stainless steel is strongly affected by its microstructure, which results from the sintering treatment controlled parameters and atmosphere [1,4].…”

“…After that, this powder is pressing and sintering under controlled temperature and atmosphere conditions inside furnaces [7]. When powder aggregates of stainless steels are sintered, necks are created among the particles and densification occurs due to diffusion mechanism, which confers strength, and inner porosities distribution [5,6]. Porosity is controlled in the manufacturing of filters, around 25 to 35% and commonly achieves 50%, depending on the application of the material [9].…”

“…Previous works have suggested the importance of adequately quantifying of microstructure and porosities [4][5][6][7]10]. Three-dimensional techniques, such as, sectioning and numerically reconstruction of the pore structure have been successfully developed and applied for quantifying important parameters of the microstructure for porous materials.…”

Microtomografia Computadorizada De Raios X Aplicada À Caracterização De Porosidade Em Pelotas De Minério De Ferro

“…Figura 38 -Valores médios de porosidade relativa das pelotas em cada um dos estágios de produção [37]. 58…”