Ceramic vs. PVD coating vs. DLC

[breitling&omega]

With the recent explosion in popularity of black watches. Terms like Ceramic, pvd and DLC have come up often in the description of material utilized in time pieces. Can someone share their wisdom and try to explain just how these are different and perhaps which is a coating versus a material that is simply uniform throughout the layers in the watch case. Many black watches in the past were not very durable and any damages to the surface material will reveal the bare alloy underneath. Is this still true?

thanks

[ThinkBachs]

I've been looking at these as well and my biggest concern is that being clumsy, I know that I'll get a mark in it. Probably not even worth considering for someone like me but the durability issue is one that I share as well...

[Guest avitt]

Without getting too deep into it...

PVD is a process (stands for Physical Vapor Deposition) for applying hard surface coatings to various substrate materials. There are several different types of coating which are applied by PVD. They all have slightly different characteristics, based on their chemical and structural makeup.

DLC stands for Diamond Like Carbon, and it is another type of hard coating which can be applied using the PVD process. DLC can also be applied using other techniques, such as CVD (Chemical Vapor Deposition), or PA-CVD (Plasma Assisted CVD), but PVD is the most cost-effective method.

DLC has characteristics which are different from other PVD coatings, including a greater surface hardness, and lower coefficient of friction. These qualities, along with the beautiful, uniform color, are the reasons why most OEM watch manufacturers are using DLC as the hard coating of choice.

The use of the word "ceramic" is a little murky... Some Swiss watch manufacturers actually do construct their cases from solid ceramic material. However, most that use the term (including all rep manufacturers, AFAIK) are actually referring a PVD coating applied to a polished metal case. For instance, at high temperatures, the aluminum in AlTiN converts to aluminum oxide, forming a ceramic layer. So it's not wrong to refer to these coatings as "ceramic"...it's just a little misleading.

[Guest avitt]

Many black watches in the past were not very durable and any damages to the surface material will reveal the bare alloy underneath. Is this still true?

Oh....And in answer to that last question: Hard surface coating are very thin, and can all be damaged by a sharp blow (one which is hard enough to remove some of the metal underneath, along with the coating). Today's PVD coating are very durable against normal wear and tear, however, including most of the normal whacks and scrapes that you'd give your watch.

[breitling&omega]

Thanks for the very informative response. Do you know what IWC uses on their top gun watches? They call them ceramic.

[Guest avitt]

The IWC Top Gun cases are solid ceramic, around an iron inner case. IWC uses a process called Ceramic Injection Molding - This is from their maketing blurb:

"Case blanks today can be moulded more efficiently and more accurately than previously from the mixture of zirconium oxide powder and binder. They are baked at temperatures between 1,500 and 2,000 degrees Celsius and then cooled in a complicated process to enable the material to acquire all its outstanding properties. Diamond-tipped tools are required for the intricate finishing of the blanks. The combination of ceramic and titanium for the case back and the operating elements is one of the distinctive features of all future TOP GUN models. In spite of the impressive size of the case, the use of modern materials, including the black nylon strap, enables a relatively low weight and comfortable wearing characteristics to be achieved.

TOP GUN, in relation to an instrument of this class, naturally also implies maximum protection of the movement against magnetic fields by an inner case made of soft iron."