Flame Spray Ceramic Coating Process

Ceramic Features

• Ceramic's basic composition is made of clay. An item resists damage, heat and corrosion once the clay hardens around an item. This protective cover is especially important for electronic components. Items as varied as computers or smartphones become very hot during operation. Components, without a protective thermal coating, are subject to heat damage and possible melting. Damaged components lead to printed circuit board (PCB) failure, causing the item to break down.
  
  

Heat Production

• The flame spray ceramic coating process requires an extremely high temperature of 5,500 degrees Fahrenheit. A specialized flame spray gun produces this high temperature through burning of oxygen and acetylene. Acetylene is a hydrocarbon molecule, typically used for heat during welding processes. The high temperature emitted by the gun can effectively melt the ceramic around an item.
  
  

Wire Spray

• Flame spray guns can work with ceramic in the form of a thin wire. A worker places an item in front of the flame spray gun. The ceramic wire feeds through the gun's center, entering the heated flame at the end of the gun's nozzle. The ceramic wire begins to melt. As the material melts, compressed air converts the melted ceramic into spherical particles. The compressed air forces the particles away from the gun and onto the item, or substrate.
  
  

Powder Spray

• Powder spraying functions the same as the wire spray process, except the ceramic is in powder form. The powder is forced through the flame spray gun onto a substrate for hardening.
  
  

Substrate

• The substrate does not become damaged through the flame spray process, regardless if it is wire or powder processes. In fact, the substrate does not heat any higher than 250 degrees Fahrenheit. This impressively low substrate temperature allows flame spray processes to apply across many sensitive items without any heat distortion or damage.
  
  

Disadvantages

• Although flame spray processes are relatively inexpensive for industry production, the procedure does have its disadvantages. The particles have a low speed, or velocity, against the substrate compared to other ceramic application processes. As a result, ceramic bonding strength is low and can contain many impurities that compromises the substrate's structural integrity.