Tempered or toughened crystals are produced through a specific thermal treatment called tempering, which increases their mechanical strength and thermal shock resistance by up to four to five times. To obtain tempered crystal, the glass sheets must be placed inside a special furnace heated to the “glass transition temperature,” or tempering temperature, of approximately 640 °C, and then abruptly cooled with jets of cold air. This process hardens the surface layers of the crystal, which contract while the inner part remains hot and viscous.
Choose Tempered Crystals for Your Safety
Due to the thermal treatment, tensions are triggered within the tempered crystal sheet that oppose external bending forces. In the event of breakage, these tensions cause the glass to crumble into tiny, blunt, and harmless fragments. When tempered crystal breaks, the tension and compression forces inside the sheet cause cracks to form instantly in all directions. Instead of breaking into a few sharp and dangerous pieces like ordinary glass, the tempered crystal shatters into many small, non-sharp fragments.
It is precisely because of this characteristic that tempered crystal is classified among safe materials for people (safety glass), capable of ensuring high levels of passive safety. In addition to passive safety, it provides active security—the ability to protect people and property from vandalism, break-in attempts, robbery, or smashing. Tempered crystals possess high levels of robustness and shatterproof resistance, making them excellent anti-intrusion, anti-smash, and accident-prevention products. Indeed, tempered crystals stand out for their superior mechanical resistance, strength, and durability against bending, thermal shocks, and forced entry, ensuring long-lasting comfort.
The Applications of Tempered Crystals
Typical applications of tempered crystals include the creation of architectural, structural, and furnishing elements, such as glass partitions and dividers, table and coffee table tops, cabinet display cases, internal sliding or swing doors, shower enclosures, parapets, canopies, fixed and mobile dividers, glazings, windows, shelves, car windows, and much more. Vetreria Re, active in the field of glass processing and the design and production of architectural and structural elements in tempered crystal—including custom solutions—is available to its select international clientele to create structural or furnishing elements with a high-quality finish and excellent acoustic silence.