iPhone4 is considered as the most classic and most Steve Jobs product of Apple. In 2020, the iPhone will be completely transformed with a metal frame similar to the iPhone4, with a square stainless steel frame to replace the current alloy frame, and will continue to use the front and rear glass as the main body of the device. After iPhone4 and 5, the iPhone series has gradually transformed into a round-case design, but with this new iPhone released, the outlook of the phone seems to go back to the square and metal design like iPhone4.
The stainless steel of the iPhone12 is knowing for its "surgery level" which means that it can be used in the surgical instrument.
What is the stainless steel of the surgical grade?
Stainless steel (or stain-resistant steel) is the most commonly used metal alloy in the manufacture of surgical instruments. Austenitic 316 (AISI 316L) is a widely used stainless steel called surgical steel because it is tough and corrosion resistant. It is widely used in the chemical industry. AISI 301 is the most commonly used metal for manufacturing medical springs. It can gain elasticity during the cold rolling process but loses corrosion resistance.
The surgical instrument is strict in the material chosen. First, the material is required to be ductile. The material ensures the easiness to shape because many surgical instruments are long and thin, such as scalpels, forceps, scissors, and no deformation during the usage because you will never want to see the instrument bending on the operation table. Second, the metal surface of the surgical instrument needs to be easy to clean and to a certain extend, antibacterial, preventing wound infection. Stainless steel can withstand high temperatures up to 400°C, which means it can be sterilized without any deformation.
Most surgical instruments are made of metal alloys. Stainless steel has always been the material of choice for metal alloys, but there are other alternatives when necessary.
Why is stainless steel back on iPhone?
Besides the characteristic like corrosion resistance, stainless steel is not only more expensive compared to aluminum alloy, but also more extravagant in the texture. For practical usage, as it is mentioned above, surgical stainless steel is suitably ductile as well as tough. If you remember, iPhone6 once faced a problem that it can be bent easily. The reason is that aluminum alloy is soft, which can easily leave stretch or even be bent. Stainless steel solutions can change this drawback that it can maintain the shape during daily usage. Typically, the iPhone12 pro max is said to have the largest screen <6.7 inches (2778 x 1284)> ever. Considering the safety and weight, stainless steel case shall be a good choice.
Moreover, the iPhone was criticized for its bad signal before. Technically, as the 5G era approaches, the requirement for the signal is getting higher. For the function of wireless charging, stainless steel case and design will improve the signal service. Materials with excellent structural properties like stainless steel or titanium alloys will be widely used on the 3C products to maintain the strength of the fuselage and support the large screen.
------------------------------------------------------------------------------------------------Stainless Steel------------------------------------------------------------------------------------------------