Iron precipitation in basalt fibres embedded in partially pyrolysed methylsiloxane matrix

0504971 - ÚFM 2020 RIV GB eng J - Journal Article
Halasová, Martina - Kuběna, Ivo - Roupcová, Pavla - Černý, Martin - Strachota, Adam - Chlup, Zdeněk
Iron precipitation in basalt fibres embedded in partially pyrolysed methylsiloxane matrix.
Composites Part A-Applied Science and Manufacturing. Roč. 123, AUG (2019), s. 286-292. ISSN 1359-835X. E-ISSN 1878-5840
R&D Projects: GA ČR(CZ) GA17-12546S
Grant - others:AV ČR(CZ) StrategieAV21/5
Program: StrategieAV
Institutional support: RVO:68081723 ; RVO:67985891 ; RVO:61389013
Keywords : Pyrolysis * BCC iron * Precipitation * Basalt fibres * Composite * Crystallisation * TEM * SEM * Mössbauer spectroscopy
OECD category: Composites (including laminates, reinforced plastics, cermets, combined natural and synthetic fibre fabrics; Polymer science (UMCH-V); Composites (including laminates, reinforced plastics, cermets, combined natural and synthetic fibre fabrics (USMH-B)
Impact factor: 6.444, year: 2019
Method of publishing: Limited access
https://www.sciencedirect.com/science/article/pii/S1359835X19302015?via%3Dihub

Composites investigated in this article owned the highest fracture resistance after pyrolysis at 650 °C. Above
700 °C the mechanical properties of the composites deteriorated as the matrix transformation and fibre crystallisation
progressed. In this work, it was found that the crystallisation processes in fibres were affected by
diffusion of pyrolysis gases through the fibre–matrix interface. Additional annealing in oxidative atmosphere
distinctly changed the crystallisation processes, resulting in a slightly improved fracture toughness of the
composites. Microstructural changes in the composite were investigated using SEM, TEM, and Mössbauer
spectroscopy. Crystals of elemental iron (Fe0) were found in the fibres. Their formation can be explained by the
reduction of ferrous (Fe2+) ions initially present in the fibres by pyrolysis gases (hydrogen, methane) released
from the pyrolysing matrix. The BCC lattice of the Fe0 particles was clearly assigned by comparison of measured
diffraction patterns with reference data as well as by the Mössbauer spectroscopy
Permanent Link: http://hdl.handle.net/11104/0299339