FAQ
Welcome to the Frequently Asked Questions (FAQ) page of AdvaMat s.r.o. We are a leading provider of advanced materials and nanotechnologies, delivering innovative solutions across a wide range of industries. Here you will find answers to the most common questions about coatings.
#1 How does PVD coating work?
#2 Why use PVD coatings?
#3 Which materials can be coated?
#4 What types of materials can be coated?
#5 How thick are PVD coatings?
#6 Can PVD coatings be applied to all shapes and substrates?
#7 What types of PVD technologies exist?
#8 How does PVD coating affect surface roughness?
#9 What is the best surface treatment for PVD-coated injection molds?
#10 What are DLC coatings?
#11 What types of DLC coatings are there?
#12 What are the applications of DLC coatings?
#13 How long does a PVD coating last?
#14 What are the anti-corrosion properties of PVD coatings?
#1 How does PVD coating work?
In the PVD coating process, parts are placed into a chamber where a clean vacuum of around 1 mPa is created. Plasma is then generated to etch target materials, releasing atoms that deposit onto the substrate and form either a ceramic or metallic layer. Once the coating is complete, the substrate is removed and the process is finished. For more details, visit our page on PVD Technology.
#2 Why use PVD coatings?
PVD coatings are characterized by high hardness, excellent resistance to corrosion and wear, and outstanding friction properties. These qualities ensure long service life and reliability of coated parts.
#3 Which materials can be coated?
PVD coatings can be applied to a wide range of materials, with the choice of deposition equipment depending on the substrate:
Tools: Specialized equipment is designed for coating cutting, forming, and machining tools. These systems ensure high hardness and excellent wear resistance.
Glass: Glass coating requires chambers with rapid pumping systems to remove excess gases and achieve clean, defect-free layers. This process enhances both optical and protective properties.
Plastics: Plastics require low temperatures and fast processing to avoid deformation. PVD coatings improve scratch resistance and provide an attractive decorative finish.
Thanks to different technologies and equipment, almost any material can be coated when the right process is used, allowing the technology to be tailored to the specific needs of diverse industrial applications.
#4 What types of materials can be coated?
Možnosti povlakování závisí především na teplotní odolnosti materiálu. Zatímco některé kovy zvládnou teploty až 500 °C, zušlechtěné oceli vydrží nejvýše kolem 180 °C a hliníkové slitiny (např. dural) ještě méně. Běžné PVD procesy probíhají při teplotách 350–400 °C, což pro tyto materiály není vhodné.
Díky technologii HiPIMS jsme však schopni aplikovat tvrdé povlaky i při nižších teplotách bez kompromisů v kvalitě, například plasty. Při správné volbě parametrů lze PVD přizpůsobit i pro materiály, které by jinak nebyly povlakovatelné.
#5 How thick are PVD coatings?
The thickness of PVD coatings typically ranges from 0.5 to 5 micrometers (µm), depending on the application. For tooling applications, layers of 2–3 µm are most common, as thinner coatings adhere better to the substrate while still providing the required hardness and wear resistance.
Decorative or optical coatings are often even thinner—sometimes only a few hundred nanometers. In contrast, certain specialized multilayer or multifunctional coatings can exceed 10 µm. The key is always finding the right balance between coating thickness and adhesion to the substrate.
#6 Can PVD coatings be applied to all shapes and substrates?
From a technical perspective, a wide range of shapes and materials can be coated, but there are practical limits. Deep cavities are particularly challenging, as it is difficult for the coating to penetrate evenly. Size is another factor—the part must fit inside the vacuum chamber, which has fixed dimensions.
The geometry of the part also affects process efficiency. Flat substrates, such as glass or films, are best suited for flat-geometry systems, while complex or larger shapes require special approaches. The ideal parts are compact with uniform dimensions, allowing for consistent and cost-effective coating deposition.
#7 What types of PVD technologies exist?
The most common PVD methods include arc evaporation and magnetron sputtering.
Magnetron sputtering works by removing material atom by atom from targets in a plasma environment. Argon ions bombard the target, releasing atoms that then deposit onto the substrate.
Arc evaporation differs in that it creates an arc discharge on the target, evaporating material in larger clusters, which can sometimes result in droplet formation.
A comparison table outlining the advantages, disadvantages, and suitable applications of HiPIMS, arc evaporation, and magnetron sputtering can be found on our PVD Technology page.
#8 How does PVD coating affect surface roughness?
PVD coating has almost no effect on surface roughness, as the layer is deposited atom by atom. Imagine it as a thin layer of snow covering a mountain landscape. If the surface was polished before coating, it will remain polished afterward. If it was ground or had a certain roughness, that same texture will remain.
Therefore, PVD coating should not be expected to improve surface finish quality.
#9 What is the best surface treatment for PVD-coated injection molds?
There are two main strategies to improve mold release in injection molding:
Sandblasting and coating: This method is suitable when working with plastics that are less flowable or when using lower injection pressures. Sandblasting creates a rougher surface, which helps with part release.
Polishing and coating: This approach is ideal for plastics with good flowability and when higher injection pressures are used. Polishing produces a smooth surface that makes part release easier.
In practice, it is always necessary to test which chemical interaction between plastics and coatings works best, as there is no universal solution. For example, CrN (chromium nitride) coatings often perform better than bare steel, but other PVD coatings may be even more effective for specific applications.
#10 What are DLC coatings?
DLC coatings are a special type of PVD coating based on carbon. DLC stands for Diamond-Like Carbon, which refers to carbon with diamond-like properties. These coatings combine the hardness and durability of diamond with the low friction and self-lubricating qualities of graphite.
By combining diamond-like and graphite-like structures, DLC creates a surface that is both strong and low-friction. The DLC family includes different variations: some are made purely from carbon, others from carbon and acetylene, and some are doped with metals to enhance performance in specific applications.
The choice of the right DLC coating depends on its intended use. Certain DLC types are designed for use with lubricants, while others perform without them. Some are used mainly for decorative purposes, while others provide protection against wear, abrasion, or corrosion.
#11 What types of DLC coatings are there?
DLC coatings can be broadly divided into doped and undoped types:
Doped DLC coatings: In addition to carbon and residual gases such as hydrogen, these coatings contain metal atoms such as tungsten, chromium, or titanium. Within the coating, these metals form carbides that provide additional mechanical or chemical properties, making them suitable for specific applications.
Undoped DLC coatings: These consist of pure carbon, typically in the form of TAC (Total Active Carbon) or ACH (Activated Carbon High). While TAC and ACH offer excellent non-stick properties, they may not interact well with lubricants. Undoped DLC coatings are characterized by high hardness and low friction, making them ideal for applications where minimal adhesion and wear are critical.
The choice between doped and undoped DLC coatings depends on the application’s specific requirements—such as the need for wear resistance, chemical stability, or compatibility with lubricants.
#12 What are the applications of DLC coatings?
DLC coatings are widely used thanks to their outstanding properties, such as low friction and high durability. Some of the key applications include:
Self-lubricating layers with low friction: Applied to gears or bearings to minimize friction and extend component lifetime.
Injection mold components: Used on slides or ejectors where low friction, long lifetime, and prevention of sticking are critical.
Decorative and protective coatings: Applied to items like knives or watches, where they combine an attractive finish with scratch and wear resistance.
With these advantages, DLC coatings are ideal for both industrial and consumer applications. Interested in our decorative coatings?
#13 How long does a PVD coating last?
A PVD coating is generally very hard and resistant to corrosion, but its lifetime depends on the specific application and correct use.
Cutting tools: Lifespan can be just a few minutes, depending on machining conditions.
Slides or mold components: Typically last hundreds of thousands of cycles, offering high durability in repeated use.
Protective and decorative coatings: Can last for decades, providing long-term protection and an attractive appearance.
#14 What are the anti-corrosion properties of PVD coatings?
PVD coatings can provide excellent corrosion resistance, but their performance depends on selecting the right coating type and deposition technology. Different processes, such as arc evaporation, DC magnetron sputtering, or HiPIMS magnetron sputtering, deliver varying results.
HiPIMS sputtering offers the strongest corrosion protection. Thanks to its high ionization, the coatings are extremely dense and free of defects or droplets, ensuring outstanding durability.
Chromium nitride (CrN) is generally considered the best anti-corrosion coating. Chromium is naturally resistant to corrosion, and when combined with the hardness of CrN, it provides superior protection. However, achieving maximum performance depends on applying the right deposition technology. Read more about our alternative to traditional chrome plating.
If you don’t find the answer to your question here, feel free to contact us. Our goal is to provide the best possible support to our customers and partners.
Matěj Buřil