Thermal spray processes are used to spray melted materials onto various surfaces. There are a number of different sub-processes that can be used. Three of the most common are plasma spraying, arc spraying, and HVOF spraying.
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Plasma spraying
Plasma spraying is a popular thermal spray coating process used in a number of industries. Its main advantages are:
– Higher quality of coatings
– An extensive range of coating materials
– Can coat many types of substrate material
– Is a well-established coating process
– Can use a broader powder particle size range than other methods
The main downsides are that it requires expensive equipment, struggles with small diameters, and the equipment cannot be manually operated.
Arc spraying
Arc spraying is most commonly used for protection against corrosion and component reclamation. Its many advantages include:
– Deposition rates of 15kg/hr or higher
– Lower cost due to lower energy cost, high deposition rates, and other efficiencies
– Lower power input than alternatives
– Minimal operator training required
– Better at metallizing thermally sensitive substrates
– Able to produce mixed coatings such as copper/steel on brake discs
– Can achieve higher bond strength than flame spraying
– Lower porosity levels than flame spraying
– Fewer H&S risks than other similar processes
The main disadvantages are that it can only be used on electrically conductive materials, the process produces a significant amount of dust/fumes, and the coating quality is lower than plasma or HVOF spraying.
If your business could benefit from the knowledge of an expert, why not take a look at the website of a thermal plasma spray specialist today? If you are looking to manufacture HAp coatings, please note that thermal plasma spray techniques are the only processes with FDA approval.
HVOF spraying
High-Velocity Oxygen Fuel (HVOF) spraying is a process that is primarily used to improve/restore a component’s surface properties and/or dimensions. Its advantages include:
– Higher density (lower porosity)
– Lower oxide content
– Better retention of powder chemistry
– Higher strength bonding to the substrate
– Improved cohesive strength
– Smaller powder sizes
– Better wear resistance
– Harder/tougher/thicker coatings
– Improved corrosion protection
The main downsides are complexity, initial investment, and the need for automated rather than manual operation.