CrN provides an unmatched combination of high abrasion resistance, low friction levels, superior corrosion protection, and thermal stability, making it suitable for applications requiring superior surface properties and outstanding durability. Receive the Best information about CrN Beschichtung.
CrN’s crystalline structure plays an enormous role in its mechanical characteristics and surface morphology. A more compact structure and higher hardness, for instance, results in reduced friction coefficients and narrower wear tracks.
Hardness
Hardness is a significant factor in CrN coating’s resistance to mechanical stress and wear, as well as high temperatures and dry environments. Because it withstands these elements well, CrN coating has proven its worth in various applications, including heavy-duty forming. Our customers who were polishing their dies every 300 to 500 hits now enjoy up to 25,000 hits without having to polish again due to our resilient chrome nitride coatings.
The oxidation resistance of this coating is also excellent, with aluminum turning into aluminum oxide when heated up, creating an extremely effective barrier against corrosion and erosion – making it suitable for applications from metal forming at higher temperatures to cutting and punching.
Not only is the coating hard and abrasive wear-resistant, but it is also chemically inert—meaning that it won’t chemically react or corrode with most counter materials. Furthermore, the FDA and USDA have approved this coating for use on food processing equipment and medical-surgical devices.
Liu et al. compared the mechanical and tribological performance of multilayer CrN/TiN coatings fabricated by both AIP and MS techniques; their study revealed that multi-AIP with MS-fabricated coating had a higher hardness/elastic modulus ratio compared to DCMS samples.
Hardness enhancement in multilayer coatings can be attributed to improved interconnectivity between crystal grains and increased atomic bonding, which contributes to excellent corrosion performance. Figure 4 displays this evidence when comparing CrN coating deposited via HiPIMS and DCMS at equal average target power; HiPIMS shows more intense peaks, indicating better crystallinity (compare the intensity of the HiPIMS peak with the DCMS sample in Figure).
CrN is resistant to thermal shock and vibration, making it an excellent choice for dynamic applications where loads might come suddenly or discontinuously. This allows coating application even in environments where conventional materials would fail.
Adhesion
CrN coating is an ideal protective layer for tools and machine surfaces due to its exceptional abrasion resistance, corrosion protection, food-grade safety, and easy application using PVD technology. Steel, HSS, and cemented carbides can all be covered at temperatures up to 450 degrees C; low-temperature versions are also available for applications involving heat-sensitive materials like aluminum.
The low-stress structure of this coating allows it to be applied much thicker than other PVD coatings (up to 0.004mm/surface) without any loss in mechanical properties or friction coefficient. Furthermore, its adhesion properties allow it to cover various machining and metalworking tools used in metallography and ceramics applications.
CrN can be applied to many hard and soft substrates, including high-speed steels such as 316 L austenitic stainless steel or SKH51 and more complex wear-resistant materials like cemented carbide, such as YG8 cemented carbide. A comparison between HiPIMS-deposited CrN coatings and those applied by DCMS demonstrated lower friction coefficients and narrower wear groove widths for those used by HiPIMS.
HiPIMS-deposited CrN exhibits superior tribological properties due to its dense, compact, and ordered structure with improved interconnectivity; this helps strengthen atomic bonds within the coating, thus increasing strength and adhesion.
CrN coatings boast superior mechanical properties that make them suitable for nuclear applications, where they can protect small Inconel 600 samples inside the Halden reactor [149]. In particular, these coatings have proven their ability to withstand corrosion by liquid heavy metals like lead and bismuth and to be coolable by supercritical water, making them up-and-coming candidates for use in future nuclear power stations; however, further studies are required to verify compatibility of different cooling media and the long-term stability of these new coatings.
Low Friction
CrN coatings’ low friction allows for faster and smoother operation, enabling fast yet accurate movements while decreasing damage risk on substrate surfaces. As such, CrN coatings make an ideal non-stick surface choice for applications such as cutting tools, molds, automotive components, and electrical devices.
This low coefficient of friction can be attributed to the coating’s distinctive structure, which features a dense and uniform atomic lattice. This gives the coating excellent mechanical properties such as hardness and corrosion resistance, as well as impressive wear performance against abrasion and sliding friction.
CrN coating is highly inert to acids, bases, solvents, caustic chemicals, and even water, providing excellent resistance in harsh environments and ensuring long service lives.
Studies have revealed that the tribological properties of CrN coatings depend on various factors, including the surface morphology, chemistry, and microstructure of the coating material. For instance, coatings with coarse columnar crystalline growth patterns tend to be more vulnerable to corrosion than denser structures; thus, optimizing their tribological properties may significantly increase corrosion resistance.
Guimaraes et al. investigated the microstructure of CrN coatings fabricated using DCMS and HiPIMS under different bias voltages without heating. Their observations included coarse columnar morphologies from DCMS, while HiPIMS deposits had dense crystalline structures.
The authors concluded that differences in morphologies were due to different levels of plasma ionization, leading to varying amounts of small crystal grains being formed in HiPIMS coatings deposited using HiPIMS. This led to dense atomic lattices with improved interconnectivity, which strengthened bonding, enhancing the tribological properties of coated material; SEM and XRD investigations verified this result.
Corrosion Resistance
CrN coating has many uses across industries due to its superior corrosion resistance and hardness, from injection molding and delicate applications requiring smooth surfaces to replacing hard chrome plating in some instances. Furthermore, its performance under high temperatures makes CrN ideal for applications that require high-speed operation requiring high-speed operation; its excellent temperature resistance also makes these coatings suitable for injection molding processes and delicate operations that need the surface to remain extremely smooth. Injection molding applications benefit significantly from CrN’s capabilities, while its performance under high temperatures makes them highly cost-efficient, as hard chrome plating can only last 6-8 minutes at most!
Coatings’ corrosion resistance depends primarily on their composition and microstructure, with factors like surface morphology and roughness also having an effect. CrN coatings, in particular, exhibit excellent chemical and electrochemical corrosion resistance thanks to the formation of a protective chromium oxide layer on their surfaces; their low friction coefficient and adhesion further add to their excellent corrosion resistance properties.
HiPIMS-deposited CrN coatings tend to have denser and more uniform microstructure than those deposited via DCMS due to its use of pulse ignition and constant plasma activation; in contrast, DCMS employs negative-pulsed target voltages with successive target voltage pulses for targeting. Furthermore, HiPIMS’ higher pulse energy allows more compact crystal grain structures.
Another factor affecting coatings’ corrosion resistance is their atomic density. Coatings with higher atomic densities possess more orderly crystal lattice structures, which result in stronger bonds between atoms. This increased interconnectivity improves mechanical properties such as hardness and wear resistance.
Researchers use a scanning electron microscope (SEM) to compare the mechanical properties of CrN coatings. This device allows researchers to inspect the surface and measure its roughness visually. A study by Li and Ehiasarian found that depositing CrN using HiPIMS instead of DCMS resulted in two times lower abrasion resistance due to thinner and more porous DCMS-deposited coatings. This allowed corrosion-causing agents into the coating’s pores, weakening its structure over time.
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