SiC Diamond Al Composite
九月18, 2025
SiC Diamond Al Composite
Low-temperature synthesizing SiC on diamond surface and its improving effects on thermal conductivity
and stability of diamond/Al composite
At DiaSemi, our mission is to deliver high-performance, reliable thermal interface materials leveraging
the superior thermal conductivity of diamond-reinforced metal matrix composites. Recent studies
reinforce our strategic direction, particularly regarding the role of interface engineering in maintaining
long-term performance under harsh environmental conditions.
Key Insights on Diamond/Aluminum (Diamond/Al) Composites Performance:
1. Challenge with Conventional Diamond/Al Composites:
Traditional diamond/Al composites suffer from thermal conductivity degradation during exposure to
moisture due to the formation and hydrolysis of Al₄C₃ (aluminum carbide) at the diamond/Al interface.
Hydrolysis of Al₄C₃ leads to the formation of Al(OH)₃ and methane gas, causing:
Interface deterioration (pores and cracks),
Weakened bonding, and
Sharp decline in thermal conductivity over time.
2. SiC Coating: A Strategic Interface Solution
To address this, DiaSemi supports the use of a SiC (silicon carbide) interfacial layer on diamond particles.
The key benefits include:
Suppression of Al₄C₃ formation, thereby improving moisture resistance.
Stable thermal performance under long-term water immersion.
Only a 6.31% reduction in thermal conductivity (from 666 to 624 W/m·K) after 500 hours of water
soaking.
This validates SiC coating as an effective barrier that minimizes diamond-Al direct contact, reduces
interfacial reactions, and enhances composite durability.
3. Thermal Conductivity Stability Modeled by Gaussian Fit
Thermal conductivity degradation follows a Gaussian trend, reflecting three distinct stages:
Stage Behavior Interpretation
Region I Gradual decline Minimal initial hydrolysis
Region II Rapid drop Accelerated Al₄C₃ breakdown and pore formation
Region III Slowed degradation Most reactive phases consumed
4. Experimental Confirmation:
SEM imaging shows heavy degradation on uncoated diamonds, while SiC-coated surfaces remain largely
intact.
XRD analysis confirms presence of Al(OH)₃ only in uncoated composites.
Coated composites exhibit no detectable Al(OH)₃, reinforcing the protective effect of the SiC layer.
5. Competitive Advantage in Thermal Conductivity:
Interlayer TC (W/m·K) Moisture Resistance
SiC (DiaSemi) 666 Excellent
TiC 650 Moderate
ZrC 572 Moderate
WC 500 Fair
Mo₂C 362 Low
DiaSemi’s Position:
This study confirms DiaSemi’s material design strategy—leveraging SiC-coated diamond
reinforcements—as a robust approach to achieving both high thermal conductivity and long-term
environmental stability in metal matrix composites.
We will continue refining our low-temperature SiC synthesis processes to enhance interfacial bonding
while preserving the thermal integrity essential for applications in power electronics, aerospace, and
high-performance computing.
