“Combo” Coatings Use Two Different Paints to Achieve Better Overall Performance
For Graphite Parts
For Graphite Parts such as rotors or stators used with degassing units where moving molten metal requires toughness and abrasion-resistance, yet non-wetting is also desired.
- FIRST COATING: Coverguard (or MW-50 or SC-1400)
- TOP-COATING: Boron Nitride Lubricoat
Note: The coatings are compatible since both have pH-Acidic (like lemon juice) systems.
For Wheel or Permanent-mold Casting
For wheel casting & permanent-mold casting, this “combo” is regularly used in order to achieve the thermal-insulation undercoat but have the best non-wetting, release, and surface finishes.
- FIRST COATING: Standard thermally-insulating mold coating
- TOP-COATING: Boron Nitride Releasecoat
Note: The coatings are compatible as BN-Releasecoat is pH-near-Neutral and OK with all pH paints.
For Metal Parts
For metal parts such ladles where a hard undercoat is desired, yet the best non-wetting is also desired.
- FIRST COATING: Boron Nitride Hardcoat
- TOP-COATING: Boron Nitride Lubricoat-ZV
Note: The coatings are compatible since both have pH-Basic/Alkaline (like housepaints) systems.
For Ceramic Parts
For Ceramic parts such as sintered-fused-silica where some surface sealing is desired along with non-wetting.
- FIRST COATING: Z-Guard
- TOP-COATING: Boron Nitride Lubricoat (regular version)
Notes: The coatings are compatible since both have pH-Acidic (like lemon juice) systems.
The Z-Guard is thin and penetrating, but penetration/sealing can be improved with vacuum-assist if available
For Used Hot-top Billet Casting Tables
For used hot-top billet casting tables that have residual Bone Ash or Red Mud on them – to seal the dust in and protect from its interaction with BN coatings.
- FIRST COATING: Z-Primercoat (see BINDERS for details about Z-Primercoat)
- TOPCOATING: Boron Nitride Lubricoat (regular version)
Note: Z-Primercoat is “forgiving” and, even though it is pH-Basic, allows topcoating with either pH-Acidic (like regular BN Lubricoat) or pH-Basic coatings. Z-Primercoat is just like housepaint primers in this application.
OTHER NOTES: Thoroughly dry the first coating before applying the top-coating. Then make sure that the “combo” is thoroughly dry before use. DO NOT CONTACT WET COATINGS WITH MOLTEN METALS. Consult MSDS before use.
PDF of Combo Coatings: Combo Coatings