Kennametal Stellite™ is the world leader in high alloy powder manufacturing. Materials include vacuum melted alloys, air melted alloys, gas atomisation, water atomisation. In addition to our high alloy materials we provide an extensive line of carbide materials. Kennametal Stellite has powder manufacturing facilities in North America, Europe and China.
The plasma transferred arc (PTA) process recommends itself due to its ease of automation and thus a high degree of reproducibility of the welded overlays. In addition, because of the highly concentrated heat source, this process benefits from high powder utilisation and can achieve a very low level of iron dilution in the overlay.
Because the hardfacing materials are in powder form, it is possible to produce overlays from many different materials and combinations of materials with a wide range of hardness and other properties. For this reason Kennametal Stellite offers the widest range of hardfacing materials for this process.
• Can Be Highly Automated
• High Powder Utilisation
• Low Dilution
• Very Wide Range Of Hardfacing Materials
In the HVOF process, powder is introduced axially into a chamber in which a gas flame is constantly burning under high pressure. The exhaust gas exits through an expansion nozzle which produces a high velocity gas stream. The powder particles are heated in this gas stream and transferred by it with kinetic energy to the surface of the work piece, forming a dense coating with excellent bonding properties.
Due to the moderate transfer of heat to the powder particles and to the work piece, which remains relatively cool, there is little metallurgical change to either the sprayed material or work piece.
Carbide – Metal combination powders specifically designed for thermal spraying.
Thermal spray coatings are used to enhance, salvage and improve component life, competing with surface treatments such as chrome plating or heat-treating. The HVOF thermal spray process produces extremely high quality coatings. Introduced over 15 years ago, Jet Kote® remains the leader in system and coating technology. It provides well-bonded, high-density coatings with high hardness, delivering outstanding performance in aggressive wear and corrosive environments.
In the Plasma Spraying Process powder is softened or melted in the plasma gas stream, which also transfers the particles to the work piece.
The plasma arc is not transferred to the work piece, it is contained within the plasma torch between an axial electrode and a water cooled nozzle. The process is operated in normal atmosphere, in a shielding gas stream (e.g. Argon), in a vacuum or under water.
Due to the high temperature of the plasma gas stream the Plasma process is especially suitable for spraying high melting point metals as well as their oxides and carbides.
Kennametal Stellite powders are gas atomised powders. Spray-Fuse & Powder Welding are available in standard size ranges.
A specially designed Oxy Acetylene torch is used for powder welding. The work piece is heated with the torch. The powder is introduced into the gas stream from the integral powder hopper and then transferred to the work piece through a flame.
This process is similar to the Oxy Acetylene process with the exception that the hardfacing takes place at lower temperatures. This minimises oxidation and distortion of the work piece ad enables easy surfacing of edges.
PM (Powder Metallurgy)
Powder Metallurgy produces fully dense pressed components and is very economic for high volume production of small simple shapes. This technology allows us to manufacture uniform microstructures, which are free of nonmetallic inclusions and defects. P/M components are proven to have outstanding wear resistance and mechanical properties and provide exceptional reliability needed for anything from aerospace bearings to industrial saw teeth.
Surface finish is typically 125 RMS, with dimensional control dependent on the part size and geometry. Components should weigh less than 0.5 lbs and have a maximum surface area of 2.5 in 2. A variety of shapes can also be extruded such as diamond, wedge, rectangular and circular sections up to 1" diameter and up to 40" long. These extrusions are excellent for hardfacing consumables, cutters and wear pads.