I. Application Background: Increasing Thermal–Acoustic–Vibration Challenges in Aircraft Modules
As modern aerospace systems evolve toward higher integration, greater component density, reduced noise, and aggressive weight reduction, onboard power systems, control modules, and avionics units are exposed to increasingly complex conditions:
Localized heat generation and rising thermal loads
Superimposed high-frequency electrical and structural noise
Continuous vibration and impact loads during flight
Extreme sensitivity to weight increases at the module level
Stringent flame-resistance requirements (no molten dripping)
A single material that provides thermal insulation, acoustic absorption, flame resistance, vibration damping, and ultra-lightweight performance is exceptionally valuable to aerospace platforms.
YDNFoam™ 4 kg/m³ aerospace-grade melamine foam was engineered specifically for these challenges.

II. Why YDNFoam™ 4 kg/m³ Is Ideal as a “Heat–Acoustic Composite Layer” for Onboard Equipment
1. Ultra-Lightweight (Only 4 kg/m³) – Exceptional Weight Reduction
Up to 1/5–1/20 the weight of traditional foams:
Reduces module weight by 120–180 g per unit
Perfect for flight control units, power modules, and motor drives
Improves aircraft endurance and fuel efficiency
2. Excellent Thermal Insulation (λ = 0.032–0.035 W/m·K)
Effectively suppresses:
Hotspots near transformers, IGBTs, and filters
Heat accumulation inside control-module cavities
Thermal fatigue during long-duration operation
Ensures stable internal temperature distribution and structural integrity.
**3. High Sound Absorption (α ≈ 0.85)
Suppresses High-Frequency Noise (4–12 kHz)**
Reduces:
Avionics module noise
Coil whine and power-converter audible noise
Mid-to-high frequency airflow and cooling-fan noise
Enhances the overall acoustic environment inside the aircraft.
4. Multi-Functional Cushioning – Vibration & Shock Absorption
Suitable for:
Flight vibration
Landing shock
High-G maneuvers
Transport vibration protection
Soft yet resilient, ensuring long-term reliability of sensitive electronics.
5. Inherent Flame Resistance (No Additives Required)
Meets:
UL94 V-0
No melt-dripping
Low smoke and low toxicity
Compatible with railway EN45545 HL3 requirements
Superior to traditional PUR, PE, EVA and other polymer foams.
**6. Wide Operating Temperature Range
(-200°C to +240°C)**
Reliable in:
High-altitude freezing conditions
Areas near warm power electronics
Severe thermal cycling environments
Maintains structural stability without becoming brittle, powdering, or collapsing.

III. Typical Applications of Heat–Acoustic Composite Layers in Aircraft Modules
1. Onboard Power Systems (Power Units)
Inner-wall acoustic liners
Thermal barriers around transformers
Shock-absorbing encapsulation
Solves: noise, local overheating, and vibration impact.

2. Control Modules (Control Unit / Flight Controller)
PCB cushioning support
Cavity thermal insulation
Structural vibration absorption
Solves: solder-joint fatigue, temperature rise, stability issues.

3. Avionics Bay / Instrument Bay
Fan-duct noise-absorbing pads
Thermal–acoustic partitions between modules
Wire harness area thermal protection
Solves: reflective cabin noise, overheating, long-term durability challenges.

IV. Structural Design Recommendations (for the 4 kg/m³ Grade)
Application Scenario Recommended Thickness Recommended Structure
Power module thermal insulation 8–15 mm Single-layer YDNFoam™
Control-module acoustic lining 10–20 mm Inner-wall installation
Equipment-bay cushioning 15–25 mm Zoned or precision-cut
Fan noise suppression 20–30 mm Flat or corrugated composite
Full heat–acoustic composite layer 12–18 mm YDNFoam™ + aluminum foil or thin fiberglass

V. Summary: The Optimal Integrated Heat–Acoustic–Vibration Material for Aircraft Systems
YDNFoam™ 4 kg/m³ aerospace-grade melamine foam delivers:
Sound absorption
Thermal insulation
Flame resistance
Vibration damping
Shock cushioning
Ultra-lightweight performance
It enhances system reliability, supports weight reduction, improves safety margins, and stabilizes the heat–acoustic environment across avionics and onboard power systems.
It is rapidly becoming an essential next-generation material for aircraft module design.

YDNFoam™ — Aerospace-Grade Melamine Foam
📍 Address:
No. 2088, Jiuliting Avenue, Caoqiao Street, Pinghu, Zhejiang, China
📧 Email: [email protected]
🌐 Website: www.ydnfoam.com
📞 Phone / WeChat: +86-135-4070-2776