September 5 - 8, 2024
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Kinetic and Thermal Spray Coating | |
Figure 1. Typical Kinetic Spray Coating System
Kinetic Spray Coating or Cold Spray Coating (see Figure 1. above) is one of the most promising technologies to achieve thick film coatings with thickness up to several millimeters (6 mm for WC-10Co-4Cr).
APT, LLC offers significant improvements to this technology by combining new high power capability (30-1,000 kW) and high pressure (1-7 bar) RF torches, generating a high temperature central core flow of medium pressure, with high pressure and medium temperature external expansion nozzle, generating annular supersonic two-phase flow. Both plasma and two-phase flows interact at the torch output prior to impacting a target substrate. Since the RF plasma torches are electrode-less, there is no contamination of the desired product. Formation of a near limitless variety of materials, properties and micro-structures is achieved with different combinations of powders, transport gases, controlled temperature levels and plasma jet targeting of the substrate. The ability of the APT hybrid kinetic/thermal technique (See Figure 2. below) allows for focused and controlled, high throughput of the processing materials, achieving thicker and more uniform, large surface area coverage of nano-structured coatings.
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Figure 2. APT RF Torch With Hybrid Kinetic/Thermal Spray Features
APT, LLC is a world leader in supplying advanced RF plasma torch features useful in a wider variety of process applications than typically available from other suppliers. These features include:
Higher plasma gas flow through the torch achieved via a patented reverse vortex stabilization technique as distinguished from conventional direct vortex stabilization
Higher thermal efficiency. For example, at 50 kW and 5 grams/sec, demonstrated thermal efficiency over 90%.
High pressure operation to 7+ bar downstream the torch(super-atmospheric) for such applications as coal and waste gasification, new materials production, aerospace testing/materials evaluations, hydrocarbons decomposition.
Scalable power and design with input power levels to 1 MW
Customized power supplies for super-atmospheric pressure torches (corresponding to up to 1 MW input per unit) and comprised of up to two independent outputs to feed different torches or torch systems that may have individually-unique operating requirements.
The flexibility of the APT hybrid kinetic/thermal spray technology is illustrated in Figure 3., showing typical operating temperature and achievable particle velocity envelopes for a wide variety of available spray coating techniques compared to the APT hybrid, kinetic/thermal design. Note the full range of thermal conditions achieved by the APT system compared to conventional approaches, while simultaneously providing enhanced kinetics.
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Figure 3. Coating Technologies Comparison
The following Table provides typical and potential operating parameter values for a variety of engineered systems unique to the APT hybrid spray configuration (nitrogen assumed as transport gas for powder introduction). It should be emphasized that the capacity of the coating systems described in the Table is limited only by the torch power since the pressure in the external nozzle expansion is limited by the plasma plume temperature reduction after mixing. Depending on the power and two-phase stream temperature (after mixing) impressive powder feed rates are achieved as well as impingement particle impact velocities (see Figure 4. below). Given that APT, LLCs RF torch power can reach the stated high MW+ levels, APT is proud to announce that its hybrid coating system is the most advanced available, offering the greatest potential for applying thin to thick, uniform and high-quality coatings over significantly large surface areas.
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Figure 4. APT Hybrid Coating System Two-Phase Stream Velocities
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Applied Plasma Technologies, LLC
4460 Whiting Road
Marshall, VA 20115
Phone: 703-340-5545
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