Strengths
Outstanding low-temperature flexibility; excellent ozone, UV and weather aging; low compression set; stable sealing over thermal cycling.
Specialty Molding Materials — FVMQ, PEEK & PA66-GF
Beyond standard solid silicone and LSR, we provide custom molding for high-performance specialty materials — FVMQ fluorosilicone, PEEK and glass-reinforced PA66. We support material selection, DFM review, mold optimization, prototyping, validation, Cpk analysis and volume production for automotive, medical, aerospace, electronics and industrial sealing projects.
How we make them: FVMQ fluorosilicone is molded on our in-house silicone and LSR equipment. PEEK and PA66-GF engineering-plastic parts are delivered as integrated multi-material manufacturing solutions through qualified production partners, with CYES SILICONE managing the DFM, mold, validation and quality documentation. This keeps our core competence on silicone while giving you a single accountable source for mixed-material programs.
Elastomer
FVMQ — Fluorosilicone Rubber
FVMQ is a premium fluorosilicone elastomer combining the broad temperature flexibility of standard silicone (VMQ) with enhanced resistance to fuels, mineral oils, hydraulic fluids and aromatic solvents.
| Property | Typical value |
|---|---|
| Operating range | -60 °C to +175 °C, short-term peak up to 200–230 °C |
| Hardness range | 40–70 Shore A |
Limitations
Not ideal for dynamic high-abrasion service; poorer tear and abrasion resistance than FKM; incompatible with phosphate ester fluids; higher material cost.
Typical Applications
Static seals, O-rings, gaskets, diaphragms and fuel-connector seals for aerospace, automotive powertrain, turbocharger, military and petrochemical systems.
Our capability (in-house): compression, transfer and liquid fluorosilicone injection molding on our own silicone and LSR equipment; custom compounding, post-cure, dimensional validation and Cpk reporting for static sealing components.
High-Performance Thermoplastic
PEEK — Polyetheretherketone
PEEK is a high-performance semi-crystalline thermoplastic delivering exceptional strength, stiffness, chemical resistance and low outgassing, with compatibility with repeated steam sterilization.
| Property | Typical value |
|---|---|
| Melting point | Approx. 343 °C |
| Continuous service | Up to 240–260 °C |
| Molding temperature | 360–400 °C (mold temperature 160–205 °C) |
Strengths
Biocompatible medical grades (ISO 10993), low ion leaching, stable dimensions, lightweight metal replacement, good electrical insulation. Reinforced grades (GF / CF) boost rigidity and reduce shrinkage.
Limitations
High molding temperature and expensive raw material; strict mold temperature control required for consistent crystallization; risk of internal stress and warpage on complex thin-wall geometry.
Typical Applications
Medical surgical components, spinal implants, dental parts, endoscopic housings, semiconductor wafer carriers, EV high-voltage connectors, aerospace structural parts, precision gears and bearing bushes.
Our capability (via qualified partners): precision PEEK injection molding, anneal stress relief, cleanroom molding for medical grades, tight tolerance control, first-article inspection and full dimensional validation — delivered as an integrated multi-material solution with CYES SILICONE managing DFM, mold, validation and quality documentation.
Engineering Thermoplastic
PA66-GF — Glass-Reinforced Polyamide 66
PA66-GF (typically PA66-GF30, 30% glass-fibre reinforced Nylon 66) is the standard structural engineering thermoplastic for high-load, high-temperature environments.
| Property | Typical value |
|---|---|
| Heat deflection temperature | Around 245–255 °C @1.8 MPa |
| Continuous operating temperature | Approx. 120–150 °C |
Strengths
Great stiffness, high tensile strength, creep resistance, good oil and hydrocarbon resistance, low mold shrinkage, balanced impact performance, cost-effective versus PEEK / PPS.
Limitations
Hygroscopic — absorbs moisture, which changes dimension and stiffness; poor resistance to strong acids and oxidizers; surface wear if used without lubrication.
Typical Applications
Automotive under-hood brackets, intake manifolds, sensor housings, EV battery and inverter components, power-tool housings, electrical terminal blocks, gears and structural supports.
Our capability (via qualified partners): precision injection molding, gate design optimization for glass-fibre orientation, moisture conditioning, dimensional stability testing, and automotive-grade QC practices aligned with IATF 16949 expectations (CYES SILICONE does not claim IATF 16949 certification) — delivered as an integrated multi-material solution with CYES SILICONE managing DFM, mold, validation and quality documentation.
At a Glance
Choosing Between the Three
| Material | Type | Best for | Continuous temp |
|---|---|---|---|
| FVMQ | Fluorosilicone elastomer | Static seals, fuel/oil contact, wide temperature swing | -60 to +175 °C |
| PEEK | High-performance thermoplastic | Medical, semiconductor, high-temp structural, low outgassing | Up to 240–260 °C |
| PA66-GF | Reinforced engineering nylon | Rigid load-bearing structural parts, under-hood | 120–150 °C |
Values are typical material specifications and are confirmed for your specific part and grade during DFM review. See our silicone material guide for standard silicone selection.
Need a Specialty Material Part?
Tell us your material, application and tolerance requirements — we'll confirm feasibility and return a DFM review and quote.
Discuss Your Material