Header menu link for other important links
Role of ZrO2on properties of machinable glass-ceramics
Published in American Scientific Publishers
Volume: 22
Issue: 1
Pages: 202 - 207
The influence of 1–5 wt% ZrO2content, heat treatment time and temperature on the crystallization behavior, crystalline phases, microstructure, hardness and theoretical machinability of fluorophlogopite mica-containing glass-ceramics were investigated in the SiO2–Al2O3–MgO–BaO–K2O–MgF2glass system. From the differential scanning calorimetry (DSC) study, it was found that the glass transition temperature (Tg), and both the crystallization peak temperature (TI pand TII p) increased with increased in ZrO2content (1–5 wt%). The progressively increase in ZrO2content has little effect on the value of Avrami exponent (n), keeping two-dimensional crystal growth mechanism. The mica crystals were identified as fluorophlogopite as a predominant crystalline phase for all three glass-ceramic specimens by X-ray powder diffraction (XRD) and subsequently confirmed by FTIR spectroscopy. The microstructure of interlocking large card-like fluorophlogopite mica crystals is found to form as seen from scanning electron microscopy (SEM). ZrO2-containing (5 wt%) glass-ceramic specimen possess lower hardness (4.51 GPa) and better machinability. Therefore, ZrO2is the most efficient nucleating agent to form fluorophlogopite mica in these glass-ceramics useful for machinable application. © 2016 American Scientific Publishers All rights reserved.
About the journal
JournalData powered by TypesetAdvanced Science Letters
PublisherData powered by TypesetAmerican Scientific Publishers