Substitution and crystallisation of fluortremolite glasses with needle-like crystal morphology

• Published in: Applied physics. A, Materials science & processing Vol. 128; no. 7
• Main Author: Werner, Dirk
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.07.2022; Springer Nature B.V
• Subjects: Applied physics; Calcium ions; Characterization and Evaluation of Materials; Chromium; Composition; Condensed Matter Physics; Crystal morphology; Crystallization; Crystals; Differential thermal analysis; Fluorine; Glass ceramics; Heat treatment; Iron oxides; Machines; Manganese; Manufacturing; Materials science; Nanotechnology; Optical and Electronic Materials; Phase separation; Physics; Physics and Astronomy; Processes; Substitutes; Surfaces and Interfaces; Thin Films; Fluortremolite; Glass ceramic; Needle-like crystal; Amphibole; Fluoractinolite
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-022-05712-9

The effect of Ca 2+ and Fe 2+/3+ substitutions for Mg 2+ on the crystallisation of fluortremolite (Ca 2 Mg 5 Si 8 O 22 F 2 ) glass ceramic was investigated by the melting of selected glass compositions at 1550 °C and thermal treatment at 950 °C. Ca 2+ is essential to generate the favoured crystal phase fluortremolite. The needle-like crystal morphology can be achieved by adding iron oxide and results in a fluoractinolite crystal phase. The DTA, XRD, SEM and TEM methods were used to identify the mechanism of phase separation of these high fluorine-containing compositions and understand the generation of the selected crystal phase. The substitution with chromium, indium, manganese and nickel offers a variety of properties for this fluoramphibole glass ceramic and as high-strength material for technical application.