Why are 2017 and 2024 aluminum alloy rivets refrigerated after heat treatment?

The refrigerating of 2017 and 2024 aluminum alloy rivets after heat treatment is primarily done to retard age hardening. When these alloys are heat-treated, they reach a certain level of hardness that is not yet fully developed. Rapid cooling through refrigeration slows down the natural aging process that occurs at room temperature, allowing the alloys to remain in a more workable state for a longer period. This is essential because it provides manufacturers with a more flexible timeline for handling and installing rivets without losing their desired properties.

Once the rivets are refrigerated, they can then be brought back to room temperature for installation, where the aging process can then proceed at a controlled rate, allowing the rivets to attain their maximum strength after installation. This method enhances the overall efficiency of manufacturing and assembly processes in aerospace and other industries, where the specific properties of these alloys are crucial for structural integrity and performance.