Thermal spray is an area of coating technology that enables the application of a very wide range of materials which provide excellent wear resistance, thermal barriers and excellent hot and cold corrosion properties. The field of thermal spray encompasses many processes that each have their own specialized applications. Over 95% of the coatings that can be applied through thermal spray processes can be given a mirror finish.
Western Hard Chrome operates three high velocity oxygen fuel (HVOF) systems. One system is the Diamond Jet, manufactured by Sulzer Metco and the other two systems are the JP-5000, a product of TAFA.
The HVOF process is capable of applying tungsten carbide matrix coatings with up to 90% tungsten carbide by weight at a bond strength exceeding 12,000 PSI, all without ever raising the temperature of your part more than 140 degrees. Furthermore, this process is capable of producing a coating with near zero porosity, i.e., less than 0.5%.
HVOF is also capable of applying a wide range of specialty alloys ranging from pure copper and alloy 718 to MCrAIY coatings, all without changing the microstructure of the base material.
Arc spray provides a wide range of possible coating materials at an economical price for resistance to corrosion, fly ash erosion, bearing area buildup and much more. Arc spray easily lends itself to automation since the process starts instantly and requires no initial warm up calibration period.
Like HVOF, arc spray is a cold application, therefore microstructure change and part distortion of the base material is not an issue.
The example at right shows an apple being sprayed with an arc spray metallic coating. Arc spray is the ultimate in low temperature metallic spray applications.
Due to the high temperature of the plasma arc, which exceeds 10,000 degrees Celsius, many types of ceramic can be sprayed for wear resistance, super corrosion properties and thermal barriers. Like the previously mentioned thermal spray systems, plasma spray does not heat the base material enough to change the microstructure or cause mechanical distortions.
Plasma spray applications span a wide range of industries from oilfield equipment to pump components along with the application of chrome oxide and titanium oxide diesel engines and gas turbines benefit from plasma applied zirconia thermal barrier coatings (TBCs), improving efficiency and reducing emissions.
Spray welding provides a metallurgical bond between the base material and the coating. This process allows for thick buildup with virtually zero porosity.
Spray and fuse consists of first depositing the desired material on the part’s surface. Then high temperatures are used to fuse the buildup, forming a continuous hard layer with a metallurgical bond.
The spray weld process will apply cobalt and nickel coatings loaded with tungsten carbide, chrome carbide and boron.
For more information on any of the thermal spray processes listed above, please call or email us.
Meet with us to learn more about our various processes and materials.