The benefits of CVD coating for metal components in harsh environments

In industries operating in extreme conditions, such as oil and gas, aerospace and energy, metal components face a number of harsh environments. Abrasive media, corrosive chemicals and erosive forces can wear down even the toughest materials, leading to component failure, costly downtime and frequent maintenance. Chemical Vapour Deposition (CVD) coatings provide a solution that enhances component longevity, improves performance and reduces operational costs.

This article explores the key benefits of using CVD coatings for metal components in harsh environments and why this technology has become a game-changer for critical industries.

Unmatched durability in harsh conditions

One of the standout properties of CVD coatings is their ability to protect metal components from abrasion, erosion and corrosion simultaneously. Unlike traditional coatings, such as hard chrome plating (HCP) or thermal spray methods, CVD coatings offer a number of key features.

High hardness and toughness

CVD coatings achieve hardness levels of up to 1600 Hv (70–77 HRc), significantly outperforming conventional alternatives like HCP. Combined with exceptional toughness, these coatings resist cracking, chipping and impact, even under heavy loads and shock conditions.

• Example - Some tungsten carbine CVD coatings are proven to be 24 times more wear-resistant than hard chrome and 6 times better than HVOF coatings in abrasive conditions​​.

Resistance to abrasive wear

Components exposed to sand, slurry, or abrasive media such as pump rotors, valves and drilling tools suffer rapid wear without proper protection. CVD’s uniform, dense layer eliminates weak points, allowing parts to resist abrasion for significantly longer periods.

• Real-world impact - In ASTM G65 abrasion tests, tungsten carbide CVD coatings outperformed tool steel by up to 30x and cemented carbide by up to 4x​​.

Superior corrosion resistance

CVD coatings form a pore-free, chemically resistant barrier, protecting substrates from aggressive substances like acids, seawater and hydrogen sulfide (H2S). This is especially critical in the oil and gas sector or chemical processing industries where corrosion is a constant threat.

• Traditional coatings often suffer from micro-cracks and porosity, allowing corrosive agents to reach the substrate. CVD coatings prevent this by creating a seamless, defect-free layer​​.

Reduced maintenance and downtime

CVD coatings directly contribute to lower maintenance requirements and extended service intervals by protecting components from wear and corrosion. This minimises costly downtime associated with repairs, replacements and equipment failures.

• Extended component life: The durability of CVD-coated components allows them to operate effectively for longer periods, reducing the frequency of replacements.
• Fewer failures in operation: Components coated with CVD maintain their integrity even in the most aggressive environments, providing reliability where it matters most.

For example, hydraulic actuators used in aerospace and industrial machinery are prone to wear and fatigue due to constant movement and exposure to harsh conditions. CVD coatings protect these actuators from abrasion, corrosion and galling, significantly extending their lifespan and reducing costly maintenance downtime​​.

Uniform protection for complex geometries

Unlike line-of-sight methods such as HVOF or physical vapour deposition (PVD), the CVD process excels at coating complex geometries and internal surfaces uniformly. This includes blind holes, narrow channels and intricate shapes that are difficult to coat with traditional techniques.

• No weak points: By ensuring uniform coverage across all surfaces, CVD eliminates inconsistencies that can lead to premature failure.
• Precision control: CVD coatings can be applied with precise thickness control (25–75 µm), meeting tight tolerances without compromising component dimensions​​.

This makes CVD the preferred solution for components such as valves, pump impellers and hydraulic actuators, where full protection of internal and external surfaces is critical​​.

Enhanced efficiency and cost savings

By reducing wear, erosion and corrosion, CVD coatings improve the efficiency of components in operation. In industries where even minor inefficiencies can lead to significant energy loss or downtime, CVD delivers measurable cost savings.

• Improved performance: Coated components maintain smoother surfaces and tighter tolerances, reducing friction, drag, and energy consumption.
• Reduced resource use: Longer-lasting components reduce the need for raw materials and manufacturing, aligning with sustainability goals.
• Lower total cost of ownership: The upfront investment in CVD coatings is offset by extended component life, reduced maintenance, and enhanced operational reliability.

For example, Hardide-coated valve components operating in abrasive slurry conditions have been shown to last up to 3 times longer than uncoated alternatives​.

CVD - the key to prolonged component life and cost savings

CVD coatings represent a transformative advancement for metal components operating in abrasive, corrosive, and erosive environments. By offering superior wear resistance, corrosion protection, and the ability to coat complex geometries uniformly, CVD significantly extends component life, reduces maintenance needs, and enhances operational efficiency.

For industries facing extreme conditions, adopting CVD technology is invaluable for reliability, cost savings and long-term performance.