Glazing tempering

Specified Glazing. The design of blast-resistant windows is currently restricted to heat-treated, fully-tempered glass in fixed... 

Meyers, G.E. "Design Criteria and Acceptance Test Specification for Blast Resistant Thermally Tempered Glass Glazing," Department of Defense Explosive Safety Seminar, Anaheim, CA, Aug 1986. 

Manufacturer inner surface outer surface inner surface I. .. outer surface ing (tempering) of product Description of glaze and body... 

Although both heat and ion tempering both successfully strengthen glass, heatstrengthening and ion tempering do not satisfy either ANSI or federal specifications for safety glazing. 

Incorporation of an outer layer having a lower coefficient of thermal expansion, as in glazing or tempering of glass. These will be discussed in greater detail in Chap. 13. 

Glaze and slip pigment analyses of ceramics from east-central Arizona Fingerprinting of Australian ocher for the authentication of indigenous art Study of shell-tempered pottery from North Mississippi... 

Many ways have been demonstrated for effectively generating surface compressive layers, some of which have been applied commercially. These include thermal tempering, ion exchange at temperatures either above or below the glass transition, surface crystallization, lamination, and glazing. 

Figure 3.12 (a) Flat tempered glazing in the popular 2 CV and (b) tempered windscreen fabricated before the introduction of annealed and laminated ones. Note the photoelastic signature left by the tempering process (Chapters 6 and 11). These signatures are better observed at dawn. Observing old cars offers surprises. One may see windshields showing a circular zone... 

A typical residual stress profile is shown in Figure 6.36. As compared to thermally tempered glazing, only a thin layer is under compressive stresses (Figure 6.25). 

Let us first consider situation (i) with a critical flaw present at glass surface either in a thermally or chemically tempered glazing, or under slowly and rapidly varying residual stresses respectively (Figures 6.25 and 6.36). We suppose the glazing is stressed uniformly and illustrate then the beneficial role played by strengthening since applied stress at rupture increases accordingly. 

Therefore, strengthening at the glass surface is directly related to the amplitude of the residual surface stresses. This means that thermally tempered glazing strength is shifted by the thermal residual surface stress amplitude. 

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