Systemen

  • HVOF - High Velocity Oxygen Fuel HVOF - High Velocity Oxygen Fuel

    Typical coatings

    • Nickel & Cobalt based alloys, Stellite,
    • Triballoy, Inconel,
    • Iron based alloys, AISI 316L, etc.
    • Carbides & Cermets
    • MCrAlY

    Main applications

    • Wear resistance Sliding, Abrasive, Erosion, etc.
    • Chemical resistance
    • High Temperature applications

    What is HVOF Spray?

    HVOF is a thermal spray system utilizing the combustion of gases, such as Hydrogen or a liquid fuel such as kerosene. Fuel and oxygen mix and atomize within the combustion area under conditions that monitor the correct combustion mode and pressure.

    The process creates a very high velocity which is used to propel the particles at near supersonic speeds before impact onto the substrate. One of the basic rules of spraying is that high combustion pressure = high gas velocity, high particle velocity and resulting high coating quality.

    One of the key benefits of this system's high velocity is the extremely high coating density and low oxide content. The low oxides are due partly to the speed of the particles spending less time within the heat source and partly due to the lower flame temperature (around 3,000 °C) of the heat source compared with alternative processes.

    As well as producing excellent bond strength, some HVOF coatings can be sprayed very thick due to the exceptionally high velocities producing coatings in compression instead of tension. This enables materials such as carbide to be applied very quickly in excess of 6mm.

  • Plasma Spraying Plasma Spraying

    Typical coatings

    • Ceramics
    • Carbides & Cermets
    • Iron, Nickel & Cobalt based alloys
    • Abradables

    Main applications

    • Wear resistance, Sliding, Abrasive, Erosion, etc.
    • Corrosion resistance
    • Thermal barriers
    • Combinations

    What is Plasma Spray?

    The plasma spraying process involves the latent heat of ionized inert gas (Plasma) being used to create the heat source. The most common gas used to create the plasma is argon. This is referred to as the primary gas. (See What is Plasma).

    Argon flows between the electrode and nozzle. A high frequency or high voltage alternating electric arc is struck between the nozzle and the electrode, which ionizes the gas stream. By increasing the arc current, the arc thickens and increases the degree of ionization. This has the effect of increasing the power and also, due to the expansion of gas, an increase in the velocity of gas stream.

    With a plasma created by argon only it requires a very large arc current (Typically 800 to 1,000 amps) to create sufficient power to melt most materials. With this level of arc current the velocity may be too high to allow materials with a high melting point to be made molten. Therefore, to increase the power to a level sufficiently enough to melt ceramic materials it is necessary to change the thermal and electrical properties of the gas stream. This is generally done by adding a secondary gas to the plasma gas stream (usually Hydrogen).

    Once the appropriate gas stream has been established for the material being sprayed, the feed stock (material in various powder forms) is injected into the gas stream.

  • Arc Wire Spray Arc Wire Spray

    Typical coatings

    • Iron based alloys
    • Nickel based alloys
    • Copper & Copper alloys
    • Aluminium, Zinc, Al/Zn alloys
    • Babbitt alloys

    Main applications

    • Wear resistance
    • Corrosion protection
    • Dimensional restoration
    • Bond coat

    What is Arc Spray?

    This form of thermal spraying uses wire material as a feed stock. An electric arc is used to provide the heat source by utilizing two current carrying wires. As the wires are fed towards each other the electric current short circuits between the wires creating a temperature of around 4,000°C. This temperature causes the tips of the wire to melt and once molten, compressed air or inert gas is used to atomize and accelerate the feed metal towards the substrate.

    One of the advantages of this system is that two different wires can be used simultaneously to produce a pseudo alloy. Cored wires are also available producing coatings with unique properties.

    The process is often used when applying to large areas such as corrosion resistance on large components or for the building up of worn components.

  • Cold Gas Spray Cold Gas Spray

    Typical coatings

    • Ductile materials & alloys, Zn, Al, Ni, Ti, Cu, Ag, NiCr, CuAl, MCrAlY's, etc.
    • High end materials: Nobium or Tantalum

    Main applications

    • Electrical and thermal conductivity
    • Pre-placement of solders
    • Corrosion protection
    • Dimensional restoration

    What is Cold Gas Spray?

    Cold spray can be considered as a new "HVOF" technology where the kinetic energy is increased while the thermal energy is lowered. With Cold Spray it is possible to spray virtually oxide free coatings.

    The coating material particles are being accelerated in a heated gas stream (600 °C), up to a particle velocity of >1000m/s. The extreme high particle velocity combined with the low particle temperature results is very dense and oxide free coatings.

    Applications are found in the automotive industry, corrosion protection and electronics industry.

  • Flame Powder Spray Flame Powder Spray

    Typical coatings

    • Self-fluxing alloys (fusing)
    • Iron based alloys
    • Nickel based alloys
    • Ceramics & Cermets
    • Abradables

    Main applications

    • Wear resistance
    • Corrosion protection
    • Chemical resistance
    • Dimensional restoration

    What is Flame Powder Spray?

    The Flame (or Combustion) Powder Spray process uses a similar technique as the Flame Wire Spray process, except that the wire feedstock is replaced with a powder. The main advantage of this process is that a much wider range of materials (such as nickel or cobalt based self fuxing alloys or ceramic materials) can be easily processed into powder form giving a larger choice of coatings. Many alloys are difficult or cannot be produced in a wire form and for this reason it was developed.

    The process relies on the chemical reaction between oxygen and a fuel of combustion to produce a heat source. This heat source creates a gas stream with a temperature in excess of 3,000°C with correctly balanced conditions between oxygen and acetylene. The feed stock material to be sprayed is fed into the flame in the form of a powder to melt and the thermal expansion of the combustion is then used to atomize and accelerate the particles onto the substrate.

  • Flame Wire Spraying Flame Powder Spray

    Typical coatings

    • Iron based alloys
    • Nickel based alloys
    • Molybdenum
    • Copper & Copper alloys
    • Aluminium, Zinc, Al/Zn alloys

    Main applications

    • Wear resistance
    • Friction properties
    • Corrosion protection
    • Dimensional restoration
    • Electromagnetic shielding

    What is Flame Wire Spray?

    This is a useful process for applying relatively inexpensive coatings that typically contain high levels of oxides and porosity together with the option of achieving a rough surface finish. The process relies on the chemical reaction between oxygen and a fuel of combustion to produce a heat source. This heat source creates a gas stream with a temperature in excess of 3,000°C with correctly balanced conditions between oxygen and acetylene.

    The feed stock material to be sprayed is fed into the flame in the form of a wire and compressed air is then used to atomize the molten metal and accelerate the particles onto the substrate.

    Among others, the process is typically used for applying bond coat materials or materials for corrosion resistance applications.