Why does Apple use a titanium frame instead of stainless steel on the iPhone 15 Pro?

When the new generation of iPhone 15 was introduced by Apple at the Wonderlust launch event, the most notable changes were seen in the premium devices, the iPhone Pro models. Not only are they equipped with the latest generation of processors, but the iPhone 15 Pro and Pro Max also utilize a new material for their frames. That material is grade 5 titanium, replacing the previous stainless steel.

Compared to stainless steel, this new titanium material has special characteristics that led Apple to use it in their new generation of high-end iPhones. 

First and foremost, the most prominent advantage of titanium alloy lies in its lighter weight and higher durability. According to Forbes, titanium is 45% lighter than stainless steel and has twice the strength of aluminum. Additionally, this material exhibits excellent resistance to corrosion and high temperatures. It is also relatively inert to chemical substances. That is why titanium is favored as a material in high-intensity activities such as aerospace and defense.

Lightweight is a clear advantage for those who are upgrading from the iPhone 14 Pro to the iPhone 15 Pro. The higher-end iPhone models are equipped with more features, which can make the device slightly heavier compared to the regular iPhone lineup. However, the titanium frame can address this drawback. In fact, the iPhone 15 Pro and 15 Pro Max are approximately 9% lighter than the iPhone 14 Pro and Pro Max.

Furthermore, depending on the composition of the titanium alloy, this material can offer various interesting characteristics. It can be extremely rigid, to the point where it is used in surgeries to fix broken bones. But it can also be flexible like plastic, allowing it to be bent and twisted without breaking, making it suitable for eyeglass frames.

In addition, titanium is much easier to electroplate compared to steel. In fact, electroplating titanium surfaces is a common method to create colors for this metallic material. As a result, manufacturers can achieve different colors for titanium, such as copper, purple, navy blue, light blue, gold, pink, vibrant red, and many others.

Currently, the new iPhone 15 Pro and Pro Max models are available in black, titanium white, titanium blue, and natural titanium colors. The use of titanium alloy as the iPhone’s frame indicates that there may be more colors to come in the future, as Apple has done with previous generations of iPhones.

While titanium brings many advantages compared to stainless steel in previous versions, it also has some notable drawbacks. Its heat dissipation performance is lower than that of steel and aluminum. Therefore, many people believe that the titanium frame may be a contributing factor to the abnormal heating of the iPhone 15 Pro during operation.

Additionally, titanium is challenging to manufacture, especially on a large scale to meet the demand for Apple’s high-end iPhone models.

Furthermore, titanium production is costly and environmentally polluting. It is a very hard metal, and most titanium parts are manufactured through machining, which means there is a significant amount of metal waste generated during production. The difficulty in titanium production also lies in the use of hazardous chemicals.

However, this is not the first time Apple has used titanium for its products. In fact, the Apple Watch released last year and even the Apple Card were previously made of titanium. Furthermore, from 2001 to 2003, Apple equipped the Powerbook G4 laptops with titanium frames. Therefore, it is likely that Apple knows how to mitigate the drawbacks of this metal when working with their manufacturing partners.