Ms. Hande Gover is a third year PhD student at the University Of Sheffield under supervision of Prof. Russell J. Hand. The focus of her study is Glass Strengthening Techniques. Prior to coming to Sheffield she worked for LAV Glass in Turkey.
Strengthening of Alkali Alkaline Earth Silicate Glasses by Ion-Exchange
H Gover*, A Leyland and R J Hand
Department of Materials Science and Engineering, University of Sheffield,
Sir Robert Hadfield Building, Mappin Street, Sheffield, S1 3JD, UK
This project involves investigation of the effects of exchanging pairs of ions, ionic species, process time and temperature on the enhancement of mechanical properties of ion-exchanged strengthened alkali – alkaline earth silicate glasses. Ion exchange is mainly a diffusional process, which takes place in a molten salt by exchanging larger alkali for smaller ones to generate surface compression below the glass transition temperature. In the current work a single-side ion exchange process has been used. In addition to ion exchange involving potassium, equivalent potassium containing glasses have been prepared to deconvolute the effect of potassium on mechanical properties. Sodium-lithium ion exchange is also being studied using specially prepared glasses. FTIR and Raman spectroscopies have been used to investigate the structural differences between ion-exchanged glasses and compositionally equivalent glasses made by direct melting (based on SEM-EDX analysis of the ion exchanged region) to enable deconvolution of features that are a direct consequence of ion exchange or due to the alkali metal species in the glass composition. Physical and mechanical property evaluation has also been conducted through four-point bending, microhardness, nanaoindentation and scratch resistance tests. Results and their relationship to the treatment conditions will be compared and discussed.