Thermal performance and application of aluminum foam

Scientific Basis of Heat Dissipation MechaNisms

1. Topological Structure Optimization

•    The three-dimensional interconnected pore network (60-90% porosity) formed via Foaming processes confers significant thermal advantages:  
•    Surface area enhancement: 20-50x higher specific surface area than Solid Aluminum, with contact areas reaching 5,000–10,000 m²/m³.  
•    Tunable pore dynamics: Adjustable pore diameters (50 μm–5 mm) induce turbulence enhancement effects.  
•    Fluid permeability: Open-cell porosity (>85%) ensures gas permeability of 10⁻¹⁰–10⁻⁸ m².  

2. Composite Heat Transfer Mechanisms

•    Forced convection: Localized turbulence within pores increases Nusselt numbers by 3- 5x.  
•    Conductive pathways: Aluminum skeletons form 3D thermal networks with 15–35 W/(m·K) thermal conductivity.  
•    Radiative enhancement: Porous structures amplify infrared radiation, achieving an emissivity of 0.8–0.9.  

Techno-Economic Analysis of Applications

1. New Energy Vehicles

•    Battery thermal management: Reduces weight by 20% and improves temperature uniformity by 15% compared to liquid cooling.  
•    Motor housings: Integrates structural and thermal functions, boosting heat dissipation efficiency by 30% while cutting weight by 40%.  

2. 5G Communication Equipment

•    AAU heat sinks: Lower surface temperatures by 8–12°C under 200 W/cm² heat flux versus traditional aluminum fins.  
•    Phase-change composites: Pores encapsulate paraffin-based PCMs, tripling thermal buffering capacity.  

Technical Challenges and Development Pathways

1. Current Limitations

•    Strength-porosity paradox: Compressive strength decays exponentially with porosity (σ = σ₀·e^(-bε)).  
•    Interfacial thermal resistance: Aluminum/air interfaces reduce effective thermal conductivity to 60–70% of theoretical values.  
•    Scalability: Powder metallurgy methods incur 30–50% higher costs than conventional heat exchangers.  

2. Innovation Frontiers

•    Gradient porosity structures: Layered designs with dense surfaces (30% porosity) + porous cores (85% porosity).  
•    Nano-coating modifications: Graphene coatings reduce interfacial thermal resistance by 80%.  
•    3D printing: Enables digital precision in pore size/porosity control.  

Market Outlook

According to Fraunhofer Institute data, the global market for aluminum foam heat dissipation components is projected to reach $1.8 billion by 2025 (24.3% CAGR), with the power battery thermal management sector accounting for over 40% of growth. Advances in additive manufacturing are expected to reduce production costs to 65% of current levels by 2030, accelerating adoption in consumer electronics.  

Future development will focus on multifunctional integration, combining electromagnetic shielding (SE >60 dB), energy absorption (12–15 MJ/m³), and thermal management into a unified bright material paradigm.  

Aluminum foam stands poised to redefine thermal engineering across industries, merging lightweight design with unparalleled thermal performance. Its evolution from niche applications to mainstream adoption will hinge on overcoming cost barriers and unlocking synergistic material functionalities.