Thermal spray technologies encompass a range of methods that enhance the surface properties of critical components across industries. Whether it’s Cold Spray for temperature-sensitive repairs, Plasma Spray for high-performance coatings, or HVOF/HVAF for dense and wear-resistant layers, each technology offers unique benefits tailored to specific operational demands.

Cold Spray is a solid-state deposition process where metal powders are accelerated to supersonic speeds using a heated, high-pressure gas, such as helium or nitrogen. There are two main variants of this process: High-Pressure Cold Spray (HPCS) and Low-Pressure Cold Spray (LPCS). HPCS typically utilizes helium as the carrier gas, allowing the deposition of materials with higher yield strength, such as Ti-6Al-4V (Grade 5 titanium alloy). High-pressure systems often require chambers for helium gas recovery, making them more economical for large-scale applications. In contrast, LPCS operates at lower pressures with nitrogen and is well-suited for softer materials like aluminum alloys, copper alloys, and commercially pure titanium (CP-Ti). The high-velocity impact causes the particles to deform and bond upon contact with the substrate, forming dense coatings without melting the material. However, due to the cold nature of the process, the bond strength of Cold Spray coatings is generally inferior to that of HVOF and Plasma Spray, as it relies only on mechanical interlocking and adhesion rather than metallurgical bonding. One of the key advantages of Cold Spray is that it does not significantly affect the substrate material, making it highly compelling for repair applications in aerospace, defense, and industrial sectors where minimal heat input is essential to prevent thermal distortion or degradation of components. However, repairing complex parts can be challenging due to the small stand-off distance required between the spray gun and the substrate, typically around 20 – 100 mm, limiting access to intricate geometries.

Plasma Spray utilizes a high-temperature plasma jet to melt and propel powder particles toward the substrate. The process typically employs argon, nitrogen, or hydrogen gases to generate plasma temperatures exceeding 10,000°C, ensuring full melting of the powder before impact. Upon contact with the surface, the molten particles rapidly solidify, forming a uniform coating. The most common type of Plasma Spray is Atmospheric Plasma Spray (APS), which operates in an open atmosphere and is limited to materials that are not sensitive to oxidation. An intermediate option is Low Pressure Plasma Spray (LPPS), which operates at reduced pressure levels compared to APS, lowering oxidation risks while maintaining lower costs than VPS. Vacuum Plasma Spray (VPS) is used for applications requiring the deposition of metallic alloys or oxidation-sensitive materials. VPS involves placing the entire system in a vacuum chamber, significantly increasing costs but allowing for a controlled environment that prevents oxidation and enables the deposition of highly reactive metals such as titanium, nickel-based superalloys, and refractory metals like tungsten. Plasma spray is widely used for thermal barrier coatings, corrosion-resistant layers, and biomedical implants due to its ability to process a broad range of materials, including ceramics and refractory metals.  

HVOF and HVAF are combustion-based spray processes that propel powder particles at supersonic velocities using a mixture of fuel (such as propane, kerosene, or natural gas) and oxygen or air. The controlled combustion process heats the powder to a semi-molten state while maintaining high kinetic energy. Upon impact with the substrate, the particles create a dense and well-bonded coating with minimal porosity. 

At AMAZEMET, we are materials scientists at heart. Our research and development team is composed of experienced PhD holders, PhD candidates, and engineers who actively publish their work in peer-reviewed journals, advancing the fields of powder metallurgy and additive manufacturing. With a firm grounding in materials science, we are uniquely equipped to tackle the complex challenges of thermal spray processes—from designing novel alloys to optimizing powder characteristics for maximum performance. This expertise drives continuous innovation in our ultrasonic atomization technology, enabling us to develop cost-effective, high-quality feedstock solutions that push the boundaries of what is possible in cold spray, plasma spray, and HVOF/HVAF applications.

Below, we invite you to explore a list of publications made possible by the AMAZEMET team and our ultrasonic atomization technology. These works exemplify our commitment to scientific rigor, real-world applicability, and the ongoing quest to elevate thermal spray research and industrial practice.