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Q&A about iPhone Finishes

← Posters: please describe Your actual situation.

Q. Apple Iphone 15 Finishing. How did Apple get the White titanium finish on the Iphone 15 Pro?

LWP Parker
- New York, NY
September 12, 2023

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Q. A friend's fingers and hands got blue staining after a day of using a new Apple iPhone 10. The front and back of the phone are glass, but the "Space Grey" stainless steel band around the phone has a dark gray or black color stainless steel band around it, with the color applied by PVD.

I assume this staining is from carbon leaching from the finish for some reason, but if someone knowledgable in black PVD could offer a comment I'd appreciate it.

Picture on iPhone screen is after using it for a day; second picture is several hours later after washing and fading.

pic of Ted Mooney
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
December 13, 2018

A. I don't think the carbon will leach out of the surface, but some of the coating might be coming off. What happens is that the coating has been deposited with very high compressive stress. Initially, it is very hard and virtually impossible to remove, so the parts go out the door. However, with thermal cycling the high stress leads to cohesive failure of the coating. It might not be the entire surface that comes off, just minute flakes that stick to your fingers. Of course, some times the entire coating flakes off. In one particularly bad case a PVD coating was applied to putter heads. The heads were painted, bonded to the shafts, packaged, and air-shipped to Japan. when they arrived in Japan all of the coating had flaked off.

jim treglio portrait
Jim Treglio - scwineryreview.com
PVD Consultant & Wine Lover - San Diego,

A. Adhesion of a coating is affected by the internal stresses of the coating as well of the substrate. For example, I find it easy to coat TiN on stainless steel but not on glass. But there is no difficulty in coating pure Ti on glass. Some electroplated substrates are difficult to coat. A common cause of poor adhesion is improper cleaning of the substrate.
In this case it appears there has been some powder formation during coating which has not been cleaned. You may wipe it with some solvent and see if the coating is completely removed. One can also do a tape test to check adhesion.
It is not necessary for the coating to contain carbon. In fact, it is not easy to deposit real black coating by PVD techniques.

H.R. Prabhakara - Consultant
Bangalore Plasmatek - Bangalore Karnataka India

thumbs up sign Thank you, Jim. Thank you, _Prabhakara

pic of Ted Mooney
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

Ruthenium use in iPhone

← Posters: please describe Your actual situation.

Q. Hello good afternoon, does any one of you know in which process of the elaboration of the iPhone they use ruthenium?

Manuel Chaides
- Tijuana, Baja California
March 24, 2022

A. Hi Manuel. Ruthenium is a conductive, tarnish resistant, precious metal. So it can be used, for example, for decorative black items; it might also be used in electrical contacts. Please introduce yourself and what you do, how you know that Apple uses ruthenium, and what inspires your question. There is too much lost motion in abstract questions and they immediately turn into stream-of-consciousness, making searchable organization of topics nearly impossible :-)

Luck & Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

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