Apple currently offers the Apple Watch in titanium, and it has offered titanium laptops in the past: the PowerBook G4. It was sold between 2001 and 2003, when it was replaced by an aluminum model.
Back in January 2021, the company received a patent for a method of giving titanium a semi-gloss finish. The patent is for a technology that involves a process of combining sandblasting and etching with a chemical anodic oxidation process to achieve a desired surface effect. Apple says the former better hides defects in the metal, while the latter offers better protection.
Titanium is heavier than aluminum, but much stronger, and thinner materials can be used to achieve the same strength and hardness, so the end result is a titanium shell that is lighter than aluminum.
It is understood that the patent begins by describing the challenges posed by titanium alloy enclosures. Portable electronic devices can include various operating components (e.g., display screens, processors, antennas, etc.). The casings of these portable electronic devices can be formed from a variety of metals (such as anodized alumina, etc.) with high strength and hardness to protect these operating parts. In addition, it is best to process these shells so that they have an attractive surface gloss. However, certain types of metals, despite their high strength and stiffness, also struggle to produce an attractive surface finish. It is therefore necessary to implement technologies for processing these specific types of metals.
The patent also describes different methods to create interesting textured surfaces, which, confusingly, is described as matte surfaces (titanium in its natural state is matte and is often polished).
Of course, Apple owns a huge portfolio of patents, only a small fraction of which can actually be used in commercial products. And Patently Apple points out that this is the eighth patent related to the material.