Apple exploring new scratch-proof coating

Ugh, I can hear the sound just by looking at that picture.

QPQ coating! I am joking. This a incredibly scratch resistant process for steel, but it comes put mottled black and not at all attractive. Funny that they ae talking about common processes in the oilfield industry.

Just cut to the chase and make them out of tungsten carbide.

One problem that I see with using nitrides is that they have certain refractory properties that may make viewing in sunlight difficult. I'm not sure if this will affect such a thin layer, although the patent does note that it brings out the natural look of the steel. But the end user isn't going to be staring at the stainless steel, they'll be looking at the screen...

There are multiple papers on the optical effects of nitrides (the patent states that they're not using titanium nitride, but fails to specify what kind of nitride), most of which are found in the Microelectronic Engineering journal. Apple may also make use of nitride-based LEDs, which increases luminosity, as well as treating the stainless steel with chromium nitride, which increases its strength.

Titanium is not a particularly strong metal. It stretches, bends and buckles more readily than steel structures of a given size. The reason it is used in airplanes is that it is very strong *for its density*, so a part with a given strength will be larger, but much lighter than a steel part. "Twice as strong as titanium" is not a big feat.

I worked on all sorts of coatings for CNC end mills. It was amazing the life we squeeze out of a chunk of metal that spun at thousands of rpms while cutting into solid blocks of steel with a coating of a few microns. We'd use teflon, diamond, and other alloys. It works.