Known as the "strongest alloy" in the iPhone, Apple's 7xxx series aluminum alloy patent was approved!
August 15, 2023
The United States Trademark and Patent Office (USPTO) has published a patent application by Apple that relates to aluminum alloys with improved material properties and curb appeal for applications including electronic device housings.
It is reported that this is a technology patent obtained by Apple after eight years to improve the performance and appearance of aluminum alloy material, and this patent is expected to be applied to future iphones, Macs and other products.
Apple notes in its new patented product background that many commercial 7000 series aluminum alloys are developed for aerospace applications and are not cosmetically attractive for use in the consumer market. Even aluminum alloys used for decorative purposes can cause anodized surface fragmentation, stress corrosion cracking (SCC), and mechanical failure.
Apple's latest invention offers the 7xxx series of aluminum alloys that perform better than known alloys and can satisfy one or more properties and/or processing variables. The new aluminum alloy can significantly reduce the surface fragmentation caused by anodic oxidation, reduce stress corrosion cracking (SCC), extend the service life of aluminum alloy, and resist impact.
In some variants, these properties can be achieved without changing the grain microstructure (for example, the average grain size, the grain aspect ratio and being as large as the grain size) or a significant loss of extrusion manufacturing capacity.
According to the test pictures, at 65°C and 90% relative humidity (RH), the failure percentage of A78 and A79 aluminum alloys in the hot soaking ASTM G30U bending test is significantly lower than that of A76.
It is worth mentioning that as early as September 9, 2015, when the launch of the iPhone 6s, Apple pointed out in public information that Apple has upgraded the aluminum to 7000 series aluminum, the same alloy used in the aerospace industry, "it is made of unique elements, making it the strongest alloy we have ever used in the iPhone." "
