PVD-Beschichtungen im Vergleich: TiN vs. DLC vs. CrN (Auswahlleitfaden 2026)

The three coatings at a glance

What PVD actually is

PVD (physical vapour deposition) vaporises a solid metal target in a vacuum, then condenses it onto the part — usually while a reactive gas (nitrogen, a carbon source) forms the ceramic or diamond-like compound. The result is a dense, thin, extremely well-bonded film. Because it’s so thin (1–5 µm) it barely changes the part’s dimensions — the opposite of a thick plating build-up.

It’s an add-on to the machined part, so it comes after CNC work. We machine and coat under one roof through our PVD coating service, which keeps the substrate prep and coating dialled in together.

TiN — titanium nitride (the gold standard)

TiN is the original and most widely used PVD coating — the gold film you’ve seen on drill bits and taps. It’s a genuine all-rounder: hard, biocompatible, food-safe, and its gold colour is a bonus that made it a decorative favourite too.

• Best for: cutting tools, punches and dies, wear surfaces, medical instruments, decorative gold hardware.
• Strengths: high hardness, good all-round wear, biocompatible and food-safe, attractive gold colour.
• Watch-outs: higher friction than DLC; the gold colour is fixed (that’s the compound, not a dye).
• Relatives: TiCN (harder, violet-grey), TiAlN/AlTiN (higher hot-hardness for high-speed cutting).

DLC — diamond-like carbon (the slippery one)

DLC is an amorphous carbon film with a friction coefficient so low it approaches dry PTFE — but with the hardness of a ceramic. It’s the coating you choose when friction, galling or wear on sliding parts is the problem. Its deep black finish is also premium-looking, which is why it dominates high-end watches, firearms and automotive trim.

• Best for: low-friction sliding parts, engine components, pump/valve internals, firearms, luxury consumer goods.
• Strengths: lowest friction of the three (0.05–0.2), excellent wear and anti-galling, sleek black finish.
• Watch-outs: lower temperature limit (~350 °C) — not for hot cutting tools; adhesion needs careful substrate prep and often an interlayer.
• Variants: a-C:H (hydrogenated, general purpose) vs ta-C (tetrahedral, hardest, extreme wear).

CrN — chromium nitride (the tough, corrosion-proof one)

CrN trades a little hardness for toughness, thickness and outstanding corrosion resistance. It can be applied thicker than TiN or DLC without cracking, which makes it the go-to for parts that see corrosion, heat and load together — and a common modern replacement for hard chrome plating.

• Best for: dies and moulds (especially for aluminium/copper), pump and valve parts, engine components, hard-chrome replacement.
• Strengths: excellent corrosion resistance, highest temperature limit (~700 °C), can be applied thick and tough, low tendency to stick to non-ferrous work.
• Watch-outs: slightly lower hardness than TiN; silver colour is less decorative.
• Green angle: a real environmental win over hard chrome, which uses hexavalent chromium.

Beyond the big three

The big three cover most jobs, but a few specialist coatings fill the gaps:

The temperature limit nobody tables

This is the spec that quietly kills the wrong coating choice. Each film has a temperature above which it oxidises or degrades — and it’s not ranked the same as hardness. DLC is the hardest option in some variants but has the lowest temperature ceiling.

Decorative vs functional PVD

PVD splits into two worlds that use the same physics. Knowing which you’re buying sets the right expectations on colour tolerance, thickness and cost.

PVD colour depends on the compound and process, not a dye — so the palette is limited to what the chemistry produces (gold, black, silver, bronze, rose). For a wider colour range or non-coatable metals, compare with anodizing in our Type II vs Type III anodizing guide and the broader surface finishing guide.

Substrate & dimensional rules

• Substrate must survive the process temperature. Standard PVD runs 150–500 °C; hardened tool steels are fine, but some tempered or age-hardened parts can lose properties — check the temper.
• Dimensional impact is tiny. At 1–5 µm, PVD rarely needs tolerance compensation — unlike anodizing or plating. Still flag press-fit and thread flanks if micron-level fit matters.
• Surface finish shows through. PVD is conformal and thin, so it reveals the underlying finish. Polish before coating for gloss; the coating won’t hide machining marks.
• Clean, prepped surfaces are everything. Adhesion depends on meticulous cleaning and sometimes an interlayer (especially DLC). Oils, oxides and fingerprints cause flaking.
• Mask what shouldn’t be coated — threads, electrical contacts, mating datums where even microns matter.

How PVD is applied

1. 1

   1. Machine & finish the part

   PVD comes last. Achieve the final surface finish first — the coating reveals, not hides, it.

2. 2

   2. Clean & prep

   Ultrasonic cleaning and surface activation remove all oils and oxides. This step makes or breaks adhesion.

3. 3

   3. Load & pump down

   Parts are fixtured (rotated to expose all surfaces) and the chamber is evacuated to high vacuum.

4. 4

   4. Ion etch / interlayer

   A plasma etch cleans at the atomic level; an adhesion interlayer is applied for demanding coatings like DLC.

5. 5

   5. Deposit the coating

   The target is vaporised (sputtering or arc) and condenses with the reactive gas to build the film micron by micron.

6. 6

   6. Cool, unload, inspect

   Verify colour, thickness, adhesion (e.g. Rockwell/scratch test) and coverage of critical surfaces.

Which coating should you choose?

Not sure which fits your part and duty cycle? Send the drawing and the service conditions to our engineers via the PVD coating service and we’ll recommend the coating, thickness and masking before the part is coated.

Frequently asked questions

The questions engineers ask most when speccing a PVD finish.