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33 clicksOperating conditions of electric ovens:
Local long-term high temperature, thermal radiation, splashing grease, electrical insulation requirements, flame retardancy safety, long-term thermal aging; some applications require low odor.
Important note: Plastics shall not be used directly in heating zones inside the oven cavity with continuous temperature above 200°C. Modified nylon is only applicable to peripheral parts outside the oven, outer side of thermal insulation layers, electrical control structural components, door hinges and handle supports.
Key distinction: Long-term service temperature (UL RTI) ≠ Heat Deflection Temperature (HDT). Priority shall be given to long-term thermal aging temperature for material selection.
1) Conventional structural parts (far from heating tubes, continuous ambient temperature ≤130°C, short-term peak 150°C)
Applicable parts: Housing supports, lock bases, rotating shafts, housing fasteners, air duct supports
Preferred material: Heat-stabilized glass fiber reinforced PA66 (PA66+25~30% GF + long-term thermal stabilization system)
Long-term service temperature: 130~140°C; HDT at 1.8MPa ≈240°C
Advantages: High rigidity, creep resistance, good oil resistance, cost-effective
Optional requirements:
Live electrical components: Add halogen-free flame retardant UL94 V0, meet GWIT 775°C / 850°C glow wire requirement (mandatory safety standard for home appliances)
Appearance parts: Low precipitation & low odor antioxidant system to avoid yellowing and bloom under high temperature
Ordinary PA6 is not recommended: Severe thermal aging occurs when continuously exposed above 110°C, resulting in rapid strength loss.
2) Parts adjacent to thermal insulation cotton and heating elements (continuous temperature 130~160°C, frequent thermal radiation)
Applicable parts: Door hinge supports, thermal insulation strips, thermostat bases, oven door inner frames
Option A (Cost-effective): Heat-stabilized toughened PA66 GF30 flame retardant V0 (high-performance PA66 system)
Option B (Higher heat resistance): Glass fiber reinforced PA46 / Semi-aromatic PA6T
PA46-GF30: Long-term service temperature 160~170°C, short-term resistance up to 220°C, fast crystallization, excellent rigidity at elevated temperature; higher cost than PA66
PA6T/PA9T: Long-term service temperature 170~190°C, ultra-low water absorption, excellent dimensional stability, suitable for high-precision hinges; highest cost
PA9T is rarely adopted in electric ovens; only used for precision parts close to heat sources in high-end commercial ovens.
3) Handheld handles (outer side of thermal barrier, no direct heat exposure, impact resistance required)
Two solutions:
Structural skeleton: PA66+GF30; outer layer overmolded with soft TPE
Integrated part: Toughened heat-stabilized PA66 (non-reinforced, to prevent scratch caused by exposed glass fiber)
* High glass fiber filled materials are prohibited for handles due to rough surface; non-reinforced heat-stabilized PA66 (Grade 103HSL type) is preferred.
4) * Zones Where Modified Nylon Is Forbidden
Oven cavity inner walls, heating tube holders, locations continuously baked above 180°C
Such areas require PPS, LCP, silicone or thermosetting bakelite. Nylon will rapidly oxidize and embrittle under continuous temperature above 180°C.
Long-term thermal stabilization (Top priority)
Ordinary nylon without heat-resistant additives will crack severely after hundreds of hours above 120°C. Copper salt antioxidant system combined with metal deactivator must be adopted to resist thermal oxidative aging in air and prevent yellowing and cracking during long-term service.
Flame retardant system (mandatory for electrical components)
Halogen-free phosphorus-nitrogen flame retardant is recommended for household kitchen appliances: low smoke, non-corrosive precipitation, suitable for white/light-colored appearance.
Red phosphorus flame retardant is only allowed for black internal components, prohibited for light-colored products and maternal & infant appliances.
Requirements: UL94 V0 at 1.5mm thickness, GWFI ≥850°C.
Oil resistance modification
Electric ovens are exposed to edible oil and animal grease. PA66 inherently features good oil resistance. Avoid adding excessive plasticizers (plasticizers migrate and release odor under high temperature).
Low odor & low VOC
Required for home appliances near food. Low-volatility additives are adopted with sufficient devolatilization during pelletizing to avoid odor emission at elevated temperature.
| Material Grade | Long-term Service Temperature | Cost | Applicable Positions on Electric Ovens | Disadvantages |
|---|---|---|---|---|
| Heat-stabilized PA6+20~30% GF | 95~110°C | Lowest | Fasteners on housings far from heat sources | Prone to thermal aging; not recommended for high-power ovens |
| Heat-stabilized PA66+25~30% GF (HB) | 130~140°C | Medium | Structural supports, hinge skeletons | Fails flame retardant requirement for live components |
| Halogen-free flame retardant V0 PA66+30% GF | 130°C | Medium-High | Electrical control bases, wiring supports, door locks | Higher formulation cost for light-colored grades |
| PA46+30% GF | 160~170°C | High | High-temperature supports adjacent to thermal insulation layers | Expensive, narrow processing window |
| PA6T/PA9T+30% GF | 170~190°C | Very High | Precision components of high-end commercial ovens | High cost, rarely used for household ovens |
* The application cases shown may not fully match your target products. Please inform us of your specific requirements, and we will assist you in material selection.
