🧩 FVMQ – Fluorosilicone Rubber
(High-performance fluorinated elastomeric material, combining the elasticity of silicone with the chemical resistance of fluoropolymers. FVMQ offers superior thermal and chemical stability compared to standard silicone (VMQ).)
🔹 What is FVMQ
FVMQ (Fluoro-Vinyl-Methyl-Silicone Rubber) is a vulcanized silicone where some methyl groups are replaced by fluorinated groups. At ReplastMD, we treat this as a specialized “all-weather” seal. It maintains its rubbery properties at extreme lows (–60 °C) while resisting chemical attack from fuels and oils. As a thermoset (vulcanized) material, it does not melt under heat. It is the gold standard for turbocharger hoses and fuel system gaskets.
🔧 Composition & Properties
- Polymer Base: Fluorinated polysiloxane.
- Density: 1.35 – 1.45 g/cm³.
- Hardness (Shore A): 40 – 80.
- Operating Range: –60 °C to +230 °C.
- Chemical Resistance: Excellent (oils, fuels, solvents).
🚗 Where FVMQ is used in the automotive industry
| Component | Example parts | Observations |
| Engine Gaskets | Seals, covers, rings | Resists synthetic oils and fuels |
| Fuel Systems | Hoses, valves, fittings | Superior chemical stability |
| Cooling / EGR | Gaskets, plugs, connectors | Resists hot antifreeze and steam |
| Electrical Parts | Connectors, insulation | Stable dielectric up to 200 °C |
🔧 Welding Temperature and Methods
| Method | Compatibility | Observations |
| Hot Air | ❌ Cannot be welded | Thermoset – does not melt |
| Heat Plate (Mirror) | ❌ Impossible | Chars rather than flows |
| Extrusion | ❌ N/A | Cannot be reshaped after curing |
| Chemical Bonding | ✅ Recommended | Specialized fluorosilicone RTV adhesives |
💡 ReplastMD Recommendation: FVMQ cannot be thermally welded. For repairs, use fluorinated RTV silicone adhesives. Always clean the surface with isopropyl alcohol before bonding.