Different types of coatings, other than DLC... Their properties and applications /informative reading/

[Guest kroexist]

As you all know the DLC coating has been perhaps the most talked about coating out of all in the watch and jewelry industry over the last several years. However, besides the DLC as an option of coating there are various of other different types of coating with sharing common properties and applications in various of industries.

As it has been clarified numerous times already THERE ISN'T SUCH ANIMAL LIKE PVD COATING. In a different discussion on this board knifemaker and I went a little bit more technical into explaining what actually is PVD. Not abbreviated the whole name of the process is Physical Vapor Deposition or shortly PVD. There is a reason why i called it a process because this is exactly what PVD is... A PROCESS. By the means of Physical Vapor Deposition different coating get applied over different types of substrates /in our case here watches made out of different alloys and metals/.

It is very important to be exact and right on point when we are referring to the PVD as a concept and make a distinct difference between the process PVD and the coating itself, shortly because both things are not the same thing. Knifemaker said something very true about the role of the watchmaking companies about misleading their customers when label some of their product as they have a PVD coating. The reason why I am saying this is because there are different types of coatings that could've been used on your watch but without knowing which one it was exactly, there is no way for you know how durable the coating it is against abrasion for example.

With risk to get a bit technical about the different types of coatings out there, I decided to put something together that is quite easy to be digested in terms of info. There are several types of popular coatings done through the PVD process that are worth to talk about and get familiar with.

First off the following chart will give you a synthesizer information about the different types of coating that are used in the watchmaking industry; their properties and applications. Do not forget however that none of the following coatings were ever meant to be used as an aesthetic coating, therefore, you wont find anywhere in the application section the words "watch" and "jewelry". Also the DLC coating is not a subject of this thread as it has been alot of information floating around about it, so i do not want to get you bored with something that you have come across already.

Now lets talk about a little about the different types of coatings individually, with their individual properties and applications...

Titanium Nitride (TiN) Coating

Titanium nitride is coating that is often used due to its well balanced coating properties. It is the most used in cutting and forming of metal and decorative purposes because of its characteristic yellow color. Application of TiN coating on cutting tools extends the life of the tools, because it reduces the coefficient of friction on the surface. It helps the flow of chips, preventing deposits of material on the cutting tool edge, reduces the cutting force and heating of cutting tool. High chemical stability makes TiN suitable for use in food industry and medicine.

Application of TiN

• Machining

Machining of iron based material. It is often used for the tools for making of gears, drilling tools with low and medium cutting parameters

• Application in medicine

Coating of implants, prostheses and surgical tools.

• Decorative coating

Sanitary equipment, home appliances, clocks, weapons

• Equipment in the food industry

knives, mills, mixers

• Forming

Coating of tools for forming of metal and tools for plastic injection.

Titanium Carbo-Nitride (TiCN) Coating

TiCN is specially designed with a complex multi-layer structure, which gives it higher hardness and lower coefficient of friction than TiCN. Besides high hardness, TiCN has a high toughness and resistance to abrasion at high temperatures. These features are desirable for many applications, eg. interrupted cutting, when changed temperatures occur at the cutting edge during operation. It has successful application on milling cutters, reamers, drill bits and cemented carbide inserts. In operations of forming, TiCN reduces wear and problems that result from sticking of material on the tool.

Application of TiCN

• Machining

Milling, turning, drilling and cutting of high and low alloy steel. Suitable for machining of hard to machine alloy steel and stainless steel.

• Forming

Suitable for coating the tools for drawing, stamping, punching and pressing. Excellent in application in a wide range of forming of steel and non-iron alloys in cold state.

Chromium Nitride (CrN) Coating

CrN coatings are the best choice when resistance to wear due to friction is required as well as corrosion and oxidation resistance and good slipping when insufficient lubrication exists. The hardness of CrN coating is about 2x higher than the frequently applied “hard" chromium coating. High hardness and low toughness that involve thicker coating (up to 40μm in the car industry) have a very good adhesion to substrate.

Application of CrN

• Components in the car industry

Coating of the parts with slipping contact surfaces, exposed to atmospheric influence, oxidation and corrosion

• Components in process industry

Coating of components in hydraulics, pneumatics...

• Equipment in food industry

Coating of knives, mills, separators

• Equipment for weapon

Coating of gun barrel, shuters...

Chromium Carbo Nitride (CrCN) coating

CrCN coatings are the best choice when you require wear resistance due to friction, resistance to corrosion and oxidation as well as slipping at insufficient lubrication. CrCN layer has a higher surface hardness and lower coefficient of friction than CrN coating. It is very suitable for application on injection tools, because of the easy elimination of mould from the tool.

Application of CrCN

• Machining

Tools for milling, turning, drilling and parting at machining of non-iron metals, particularly Ti and Cu alloys.

•Forming

Tools for drawing, stamping, punching, pressing and forging at machining of non-iron metals. In particular it is used for forming of Ti and Cu alloy as well as cast aluminum and magnesium.

• Plastic processing

Tools exposed to corrosive and abrasive wear, eg. under the influence of aggressive and hard materials for the casting, can be strengthened with CrN layer.

Alminium Titanium Carbo Nitride ( AlTiCN ) coating

AlTiCN (ALTITRON) with its multi-layered structures, is a basic choice for cutting of tools for machining of stainless steel and nickel-based alloys. It is most used for coating of tools for interrupted cutting under dry, semi-dry conditions or machining with cooling.

Application of CORTITRON

• Machining

Cutting of metal under harder operating conditions (higher cutting speed, without lubrication).

Titanium Alminium Nitride (TiAlN) Coating

TiAlN (TITRON) coating give higher resistance to temperature than TiN, as well as higher hardness at higher temperatures. Coating on the tool forms thin layer of clay (Al2O3) or Aluminium oxide of ceramics. During operation and wear, the layer is continually renewed. To enable this process tha tool has to work in hot conditions.

Application of TITRON

• Machining

Specially developed for drilling operations under extreme conditions ( bad cooling or without cooling). Excellent results can be achieved in milling, grooving and metal sheets forming. Re-sharpening and recoating is possible and it is recommended.

Titanium Alminium Carbo-Nitride (TiAlCN) Coating

TiAlCN (TIALTRON) is a new generation of multilayer coatings. It has very low friction coefficient. Excellent for application in machining of all kind of steel with and without cooling or lubrication.

Application of TIALTRON

•Machining

Cutting tools for machining of low and high alloy steel at high speeds.

•Forming

Pressing and drawing of low and high alloy steel and other types of forming where friction coefficient is important.

[flim]

Thanks again for the very informative post.

[zaza]

Amazing post! Quite informative. Should be pinned!

Thanks for the huge effort.

[HauteHippie]

Another very informative post!

[dark]

Great write up. Thanks for taking the time.

[subbiesrock]

Awesome writeup. I'm stealing the picture for an entirely different purpose for some fabrication work we need done at work. What a great post!

[Watchmeister]

Great stuff. I am a TiAln man myself.