TiN, CrN, TiCrN, AlTiN, and AlCrN
A Detailed Engineering Comparison
This guide compares the five most common nitride coatings side by side to help engineers understand where each performs best.
Not all PVD nitride coatings are designed for the same environment.
While TiN, CrN, TiCrN, AlTiN, and AlCrN all improve wear resistance and extend component life, each coating has strengths and tradeoffs. Some excel in abrasive wear, others resist galling, and some are specifically designed for high-temperature oxidation.
This article compares five common nitride-based hard coatings:
TiN, CrN, TiCrN, AlTiN, and AlCrN
These coatings are all used to improve wear resistance, reduce galling, protect surfaces, and extend component life. However, they behave very differently in hot or corrosive or vacuum environments, as well as when there is sliding contact.
Quick Comparison
TiN
The Baseline Coating
Titanium Nitride, TiN, is the classic gold-colored PVD coating. It is widely used because it is proven, relatively economical, chemically stable, and available from almost every coating supplier.
| Property | Typical Range |
|---|---|
| Hardness | 20–30 GPa |
| Microhardness | 2,000–3,000 HV |
| Coefficient of friction vs. steel | 0.45–0.65 |
| Typical thickness | 1–5 µm |
| Practical air temperature range | ~450–600 °C |
| Color | Gold |
Selection Guide by Application
If the application is a moderate-temperature wear part:
Start with TiN.
Move to TiCrN if corrosion or oxidation is slightly more demanding.
Move to CrN if galling is the main issue.
If the application is a stainless steel or titanium sliding interface:
Start with CrN. CrN is often a better anti-galling choice than TiN.
TiCrN can be considered if higher hardness is needed.
If the application is high-temperature air exposure:
Start with AlTiN or AlCrN.
Use AlTiN for hot wear where high hardness is needed. Use AlCrN when oxidation resistance is the primary driver.
If the application is hot and corrosive:
Start with AlCrN.
AlCrN usually provides the best combination of high-temperature oxidation resistance and Cr-based corrosion resistance.
If the application is vacuum sliding:
Do not select from the table alone.
Test TiN, CrN, TiCrN, AlTiN, or AlCrN in representative vacuum conditions, or consider a dedicated solid-lubricant coating system.
For vacuum mechanisms, friction coefficient in air is not enough.
Reach out to us about relevant information if needed.
If the application is fatigue-critical:
Be careful with all hard PVD coatings.
Hard coatings can introduce residual stress and surface defects. Require fatigue testing or use heritage data.
Pay special attention to coating thickness, edge preparation, and substrate hardness.
Practical Ranking by Engineering Priority
Best High-Temperature Oxidation Resistance
AlCrN
AlTiN
TiCrN
CrN
TiN
Best Low-Risk Baseline Coating
TiN
CrN
AlTiN
AlCrN
TiCrN
Highest Hardness
AlCrN
AlTiN
TiCrN
TiN
CrN
Best Galling and Corrosion Behavior
CrN
AlCrN
TiCrN
AlTiN
TiN
This ranking is not universal. It is a starting point for engineering discussion.
The numbers above are typical engineering ranges for dense PVD coatings. Actual values depend on deposition method, coating thickness, substrate, interlayer, surface preparation, bias voltage, composition, and post-treatment.
Final Thoughts
Every coating represents a tradeoff between hardness, toughness, oxidation resistance, corrosion resistance, friction behavior, and operating temperature.
If you want guidance understanding the tradeoffs, contact us for a free 15-minute consultation.
