When Apple launched the iPhone 6s on September 9, 2015, it mentioned the use of 7000 series aluminum alloys used in the aerospace industry in both the press release and the product page.
According to the list released by the United States Trademark and Patent Office (USPTO) today, Apple has obtained a technical patent for improving the performance and appearance of aluminum alloy materials after 8 years, which is expected to be applied to future iPhones, Macs and other products.
The report states that commercial 7000-series aluminum alloys are mainly used in the aerospace field and are not attractive enough for the consumer market.
Also alloys designed for decorative purposes can lead to chipping of the anodized surface, stress corrosion cracking (SCC) and mechanical failure.
Apple has designed the 7xxx series of aluminum alloys in the patent to outperform known alloys for one or more properties and/or processing variables.
Apple said that the new aluminum alloy can significantly reduce surface cracking caused by anodizing, reduce stress corrosion cracking (SCC), prolong the service life of aluminum alloy, and can withstand impact.
The test picture as follows. In the heat soak ASTM G30 U-shaped bending test at 65 degrees Celsius and 90% relative humidity (RH), the failure percentage of A78 and A79 aluminum alloys is significantly lower than that of A76.