As a material science expert with a focus on glass and ceramics, I can provide a detailed response to your question regarding the heat resistance of Pyrex, a brand known for its high-quality borosilicate glass products.

Pyrex is renowned for its ability to withstand high temperatures and resist thermal shock. The primary reason for this is the composition of the glass, which includes boron trioxide, giving it a lower coefficient of thermal expansion compared to regular soda-lime glass. This characteristic allows Pyrex to handle temperature fluctuations without shattering, which is why it is often used in laboratories and kitchens for its durability and safety.

However, the specific temperature that Pyrex can withstand varies depending on the product and its intended use. For oven use, Pyrex products are designed to be safe up to a certain temperature limit, which is typically around 450 degrees Fahrenheit (232 degrees Celsius). This is the temperature at which most Pyrex bakeware can be safely used without the risk of breaking. The European made bakeware you mentioned staying intact at 450 degrees is consistent with the general guidelines for Pyrex products.

It is important to note that while Pyrex can handle high temperatures, it is still susceptible to damage if subjected to extreme temperature changes. This is why the label advises against such changes. For instance, taking a Pyrex dish straight from a hot oven and placing it in a freezer could potentially cause the glass to crack or shatter due to the rapid temperature shift.

The incident where five out of six pieces shattered when the temperature was increased to 500 degrees Fahrenheit (260 degrees Celsius) illustrates the limits of Pyrex's heat resistance. While the brand is designed to be more durable than regular glass, exceeding its recommended temperature range can result in breakage. Manufacturers often provide a safety margin in their temperature guidelines to ensure the longevity and safety of their products.

In summary, Pyrex is a versatile and heat-resistant material that can be safely used up to 450 degrees Fahrenheit for oven applications. However, it is crucial to follow the manufacturer's guidelines to avoid extreme temperature changes that could compromise the integrity of the glass. Always consult the specific product's instructions for its exact temperature limits and handling recommendations.

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The European made bakeware stayed intact at 450 degrees, but five out of six pieces shattered when the temperature was increased to 500 degrees. ... For example, a Pyrex label says --Avoid extreme temperature changes.-- But, it also said the bakeware is oven and freezer safe.Jan 26, 2011read more >>