The Strength of Silicate Glasses: What Do We Know, What Do We Need to Know?

Abstract

In the last few years, there has been increased interest in methods to improve the practical strength of inorganic glasses. During this same time period, new theoretical and experimental techniques have appeared. In this paper, we discuss this interest and indicate how and where these new techniques may help us to achieve our objective to increase the practical strength of glass. Our ability to measure the intrinsic inert strength of glass fibers as well as the development of stresses around indentations and scratches now allows us to attack these two important issues experimentally. Likewise, major advances have been made in techniques for the modeling glass structure and mechanical properties. The advances in these three areas give us indications of how changes in glass composition and processing can influence the final strength as well as its robustness.

Alkali salt vapour deposition and in-line ion exchange on flat glass surfaces

“…(31) It is approximately two orders of magnitude lower than reported Δn s values achieved via K + -Na + ion exchange, (32) which means that induced compressive stresses is the major factor of refractive index increase. In the current study, n s was calculated from the reflectance spectra at the specific wavelength of 520 nm, according to Equation (2). The reflectance spectra R% in the range 300≤λ≤550 nm are shown in Figure 9.…”

Difference of cracking behavior due to Vickers indentation between physically and chemically tempered glasses

“…Birefringence measurement is a well accepted method, since it is non-destructive and easy to use. Birefringence image perpendicular to the loading direction should be simple in order to estimate plastic deformation zone and residual stress field [13]. However, in the tempered glasses, birefringence measurement from the cross-section is difficult to be applied due to surface compressive stress.…”

Деформация И Прочность Кварцевых Волокон При Испытании На 3-Точечный Изгиб С Учетом Нелинейной Упругости Стекла

“…Это особенно важно при проведении испытаний на проч-ность в жидком азоте, когда деформации при разруше-нии могут достигать значений около 18% [3,10,11] Законы деформирования кварцевого стекла при растяжении и сжатии В общем виде можно описать нелинейную упру-гость следующим уравнением, ограничиваясь кубиче-ской степенью зависимости напряжения (σ ) от дефор-мации (ε) [3]:…”