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Aluminium Casting - Saint-Gobain Coating Solutions
Spinel spraying with the Master Jet.
Industry: Aluminium Casting Plant
Equipment: Spoons, chutes, funnels, moulds.
Principle of the Process: Aluminium metal casting requires tools to transfer the molten metal to the moulds or dies. Those tools (spoons, chutes, funnels) are made of steel.
Problem: Tools in contact with molten aluminum are subject to surface degradation and oxidation. Metal slag sticks on the tool surface.
Service Conditions:
- High temperature ~660°C (1220°F), resulting from the contact with the molten aluminium.
- Metal slag sticks at the surface of the moulds, chutes, funnels.
- Severe thermal shocks resulting from the casting cycle.
- Corrosion and oxidation can occur with several aluminium alloy (Al-Si) compositions.
Metal slag sticks at the surface of the chute.
Coating Solution: Spinel Flexicord Coating.
Benefits of the Spinel Flexicord:
- Spinel Flexicord coating provides reduced sticking (large wetting angle) versus liquid aluminum metal.
- Cleaning of the spinel coated tools is much easier and requires less time (low sticking of the metal slag).
- Spinel Flexicord coating is a thermal shocks resistant coating.
- The tools lifetime with a Spinel coating is at least twice versus tools without coating (minimum 200% benefit in lifetime).
- The spinel coating can be removed and it can be rebuilt indefinitely.
- Spinel Flexicord is easy to apply by hand on complex shapes and large components with a Top Jet or Master Jet gun.
- Spinel Flexicord coating is less stressed and less subject to spallation compared to plasma sprayed coatings.
Coating Features:
- Product Ref: 9821 070 47 000.
- ~300 coating thickness on 100 to 150 µm of NiCrAlY bond coat.
- Roughness Ra 16 µm - Porosity 17 %.
- Expansion Coefficient (C.T.E) : 8.8.10-6 at 0 – 980 °C.
- Micro Hardness: 1140 Hv300g.
- Surface weight ~890 g/m²/0.3 mm.
- Surface coverage 2 m²/h/0.1 m.