Mechanical Properties of Ag+/Na+ Ion-exchanged Aluminosilicate Glasses

Abstract

Mechanical properties of Ag Na ion-exchanged aluminosilicate glasses are investigated. The aluminosilicate glass samples with the thickness of 1 mm and homogeneous Ag Na concentrations were prepared via the ion exchange in the molten salt at 450? C and the following post-heating in the ambient atmosphere. Measured Young's modulus, Vickers hardness and fracture toughness in a dry nitrogen atmosphere change nonlinearly with increasing Ag Ag Na ratio, and show the maximum values, 75 GPa, 560 kgmm 2 and 0.84 MNm 32around Ag Ag Na 50!, respectively. Fully exchanged glass shows the same modulus 70 GPa as that of the mother glass and the smallest hardness and toughness, 500 kgmm 2 and 0.74 MNm 32 , respectively. The calculated yield stress decreases from 2.59 GPa to 2.30 GPa with increasing Ag Ag Na at more than 60! region. Coexistence of Ag Na induces mixed cation effect, and gives a maximum to the elastic modulus at AgNa 11. Additionally, the yield stress of glass is decreased with increasing Ag concentration by the difference of the effect on Al-O-Si network between Ag and Na .

Fabrication of glasses with low softening temperatures for mold-processing by ion-exchange

“…The mechanical properties of silver/sodium ion-exchanged aluminosilicate glass, which has no nonbridging oxygen, have been intensively studied by Funabiki et al 12) They showed that the (yield stress)/(Young's modulus) representing the minimum strain of the glass network to be broken was monotonically decreased with the replacement of sodium by silver ions. They have discussed the relationship between the mechanical properties and the structural aspect of the glass in detail and considered that the low coordination number of silver ions in the glass is one of the origins of the mechanical behaviors of the ion-exchanged glass.…”