Grade 5 Titanium Explained: Why Apple Chose It For The iPhone 15 Pro

During the September 2023 Apple Event, materials science engineer Isabel Yang stated that the new iPhone 15 Pro will be using Grade 5 titanium in its frame. Greg Joswiak referred to it as "the most premium material [Apple has] ever used in an iPhone enclosure." This new frame certainly sounds like a tech enthusiast's dream, but many Apple fans might be scratching their heads as to why Apple specifically chose Grade 5 titanium. What is it? How is it different from other varieties of the infamously durable metal? Does it have some special properties that make it a superior choice for smartphone design compared to other titanium grades?

Titanium alloy is known for being both incredibly strong and light compared to other materials, but not all titanium is created equally, it seems. There are four different variations of this super-metal and each of them has different properties. Some are used for surgery due to their resistance to corrosion, while others are known for their ability to be efficiently welded, or are used for their resistance to extreme temperatures. It appears that Apple chose Grade 5 titanium because it's known as the strongest.

According to the Titanium Processing Center, Grade 5 titanium is known as the 'workhorse' grade of titanium due to its superior tensile strength. This makes it the most popular variety and is estimated to make up approximately half of all titanium production in the world. It's commonly used in medical, marine, aerospace, and chemical processing applications, but it has many other uses as well. Manufacturers have used Grade 5 titanium in everything from sporting equipment to aircraft turbines.

During the event, Yang stated that Grade 5 titanium is, "an alloy that has even higher tensile strength than pure titanium. It's typically reserved for applications where the balance of strength, formability, as well as weight, are especially critical. In fact, this is the same alloy used on the Mars Rover." As if the material used to collect samples on the fourth rock from the sun didn't speak for itself, she then spoke about how this alloy has one of the highest strength-to-weight ratios that can be found in any metal.

It seems that this is the primary reason why Apple chose it. Grade 5 titanium is strong and lightweight, which has allowed the tech company to design the iPhone 15 Pro with a slimmer, lighter, and more durable frame. It's thanks to this alloy that the new smartphone has a smaller profile that doesn't sacrifice structural integrity–all while cutting the final products weight and maintaining the same size screen.