Wetting of MoNbTaW HEA coated graphite/diamond by molten copper
九月16, 2025
Wetting of MoNbTaW HEA coated graphite/diamond by molten copper
| Aspect | Details |
|---|---|
| Objective | Investigate Cu wetting on surface-modified graphite/diamond substrates for transpiration cooling in extreme environments. |
| Surface Modifications | Refractory metals: W, Nb, Ta, Mo; High-entropy alloy (HEA): WNbTaMo. Deposited by magnetron sputtering. |
| Key Reaction Products | Carbides formed: WC, Mo₂C, (WNbTaMo)C → improved wettability. |
| Cu Wettability Ranking | W > Mo > WNbTaMo > Nb > Ta. |
| Interfacial Energy (γsl) | ~923 mJ/m². |
| Interfacial Entropy Contribution | ~188 mJ/m² (20.3% of γsl). Entropy value: 0.137 mJ/(m²·K), much higher than conventional metal/metal systems. |
| Thermal Conductivity (Composite) | 518 W/(m·K) at RT; 484 W/(m·K) at 1100 °C → ~32% higher than unmodified Cu/graphite composites. |
| Self-driven Cooling | Cu/WNbTaMo-graphite composite shows spontaneous Cu exudation under oxidation (volatile oxides form → forced cooling). |
| Application Potential | High-temperature thermal management (e.g., hypersonic leading edges, rocket engines). |
#diamond/graphene#diamond/copper#HEA#Thermal conductivity
