Titanium alloy surface texture creation process

Recently, Apple has been granted another related patent.  The patent grant describes a process for creating textured surfaces on titanium alloys.  An Apple patent last year revealed the company was exploring the possibility of creating a titanium iPhone, iPad and MacBook.

Apple currently offers titanium Apple Watch and has a titanium laptop in the past: PowerBook G4. It was sold between 2001 and 2003 and was later replaced by aluminum models.

Titanium's surface was not attractive in its original state, and Apple has explored different ways to make the material look more attractive.

Back in January 2021, the company obtained a patent for treating semi-gloss titanium (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 can be thinner to achieve the same strength and hardness, so, the end result is that the titanium alloy shell will be lighter than the aluminum shell.

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 goes on to describe different methods for creating interesting textured surfaces, which, confusingly, the patent describes 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.