Titanium Alloy PVD Coating

Titanium alloy PVD coating is a thin film formed by physical vapor deposition (PVD) technology on the surface of titanium alloy. This technique can physically vaporize the surface of the material source (solid or liquid) into gaseous atoms, molecules, or partially ionized into ions under vacuum conditions, and then deposit a membrane with specific functions on the surface of the substrate through a low-pressure gas (or plasma).

Titanium alloy is widely used due to its low density, high specific strength, corrosion resistance, weldability and other advantages, but its poor wear resistance, easy oxidation and corrosion, and low surface hardness limit its application.Using PVD technology, high hardness, high wear resistance and colorful decorative coatings can be formed on the surface of titanium alloys, thereby significantly improving these properties.

The PVD coating process includes vacuum evaporation, sputtering coating, ion plating and other forms, the most common of which are vacuum arc ion plating and sputtering coating.For example, the surface of TC11 titanium alloy adopts PVD vacuum arc ion plating TiAlN coating, which can effectively improve its protective performance.

However, titanium alloy PVD coating also faces some challenges.

First of all, the fatigue sensitivity of titanium alloys is extremely strong, which makes it necessary to pay special attention to process design and control when performing PVD treatment.

Secondly, compared with stainless steel, the difficulty of titanium alloy PVD coating mainly lies in the comprehensive evaluation of stripping and repair.In addition, the cleaning process before the surface treatment of titanium alloy is also very critical to ensure the quality and adhesion of the coating.

Titanium alloy PVD coating has broad application prospects. It can not only improve the mechanical properties and bio-compatibility of titanium alloy, but also increase the aesthetics and service life of the product.

The Latest Research Progress Of Titanium Alloy PVD Coating

1. Multi-layer coating technology: Multi-layer coatings such as TiAlSiN prepared by PVD technology increase hardness through periodic interface structures.This structure can prevent the movement of interlayer dislocations, thereby significantly improving the hardness of the material.

2. Medical titanium alloy surface protection: Research in key laboratories has shown that the ZrN coating prepared by physical vapor deposition (PVD) technology has excellent wear resistance and biocompatibility, making it an important protective coating for bone implants.3. Tool wear and life: In the process of high-speed milling of TC6 titanium alloy, PVD-coated tools exhibit smaller rear tool surface wear and longer tool life, which makes PVD coating more suitable for TC6 titanium alloy processing.

4. Development trend: At present, the development trend of PVD coating technology includes harder and harder coatings and softer coatings (solid lubrication and low friction), and gradually moving towards new, composite and multi-layer directions.

Optimize The Process Parameters Of Titanium Alloy PVD Coating

1. Choose The Appropriate PVD Method: According to different application needs, you can choose PVD methods such as vacuum evaporation deposition, ion plating and magnetron sputtering.These methods have their own advantages and disadvantages, for example, vacuum evaporation deposition is suitable for the preparation of coatings with high hardness and low coefficient of friction.

2. Adjust The Coating Material: By continuously improving the coating material, the overall performance of the coating can be improved.For example, the use of titanium-nitrogen alloy as a coating material can obtain better wear resistance and corrosion resistance in fields such as automotive engine parts and cutting tools.

3. Control Process Parameters: In the PVD process, process parameters such as temperature, pressure and gas flow need to be strictly controlled.These parameters directly affect the quality and performance of the coating.For example, by optimizing the combination of etching process parameters, the best material removal effect can be ensured from the surface.

4. Enhance The Binding Force Of The Coating And The Substrate: The binding force is one of the important indicators to evaluate the quality of the coating and is used to evaluate the bonding strength between the coating and the substrate.Therefore, in the PVD process, attention should be paid to the binding force of the coating and the substrate to ensure the stability and durability of the coating.

5. Improve Oxidation Resistance: Since the coating is often exposed to high temperature and high pressure environments, its oxidation resistance affects the service life of the coating.The oxidation resistance of the coating can be improved by changing the structure and composition of the coating and adding oxygen-blocking elements.

6. Comprehensive Intervention Method: For molds with relatively poor surface hardness, ion carburizing treatment can be implemented first, and then PVD coating treatment.This comprehensive intervention method can better extend the service life of the coating.

New Titanium Alloy PVD Coating Material

Multi-layer (Cr/CrN)×8 coating: This coating is deposited on the surface of Ti-6Al-4V alloy by PVD vacuum arc method, and has the same total thickness and number of constituent layers, but the thickness ratio of the Cr and CrN constituent layers is different.

Hard film material CrN: This material is used in the CTC5240 blade of Senlacherib, which exhibits good wear resistance and service life.

1. Wear Resistance: The PVD coating combines better with the surface of the workpiece, has greater binding force, and the hardness of the coating formed is relatively high, and the wear resistance and corrosion resistance are relatively good.In particular, CrN coatings exhibit good wear resistance when efficiently processing titanium alloys.

2. Adhesion: The PVD coating has excellent adhesion and can be bent more than 90 degrees without cracking or peeling.

3. Corrosion Resistance: PVD coating not only improves the wear resistance of titanium alloy, but also enhances its corrosion resistance.

4. Fatigue Performance: PVD coating has a significant impact on the fatigue performance of the titanium alloy matrix, which can improve its performance during fatigue fracture.

5. Environmental Friendliness: The PVD process has no adverse effects on the environment, which is in line with the development direction of modern green manufacturing.

Advantages And Disadvantages Of Titanium Alloy PVD Coating

Advantage

1. Wear resistance and hardness: PVD coating can significantly improve the hardness and wear resistance of the surface of the object, making it more resistant to scratches and wear.In addition, PVD coatings maintain their color better in long-term use and are more wear-resistant than anodized coatings.

2. Corrosion resistance: PVD coatings have a high degree of corrosion resistance and are suitable for many decoration industries.No flaking phenomenon: Unlike traditional electroplating, the PVD coating will not flake.

Disadvantages

1. The deposition rate is low: The deposition rate of PVD is usually low, generally a few to several hundred nanometers per minute, which is not as good as evaporation and ion plating, or even lower than sputtering coating.

2. Equipment complexity: PVD equipment is relatively complex and may require higher maintenance costs.