Alternative route for improving mechanical properties of glasses using high pressure.

Reference	Presenter	Authors (Institution)	Abstract
10-064	Leonardo Resende	Resende, L.(Universidade Federal do Rio Grande do Sul); Buchner, S.(Universidade Federal do Rio Grande do Sul);	Glasses are defined as amorphous solids, obtained from quenching of liquids. The production of glass is a well known process and starts with the melting of oxides. The glass is formed when these molten substances are quenched, preventing crystallization. Some studies are focused on increasing the mechanical properties of glasses, either by the inclusion of other elements in the composition of the glass, or by controlling crystallization, forming a glass-ceramic. This work aims to use the high pressure technique as an alternative route to obtain glasses of high density, and, consequently, with improved mechanical properties compared to the glasses produced by the conventional route at atmospheric pressure. Samples of lithium disilicate glass (Li2O.2SiO2) were produced under high pressures (up to 7.7 GPa) and temperatures up to 1600ºC. The samples were analyzed by X-ray diffraction. The mechanical properties of the samples were measured by Vickers microhardness and instrumented indentation technique. X-ray diffraction patterns showed an amorphous material. The microhardness and instrumented indentation measurements of samples produced at high pressure compared to samples produced at atmospheric pressure indicated an increase of approximately 30% in the values of hardness, which is a promising result.
<< Back