Diamond Powder For Thermal Management
What This Process Needs To Solve
Heat is now the limit on power electronics. Copper moves about 400 W/m·K; synthetic diamond reaches 1000–2200 W/(m·K), two to five times copper, while its thermal expansion sits close to semiconductor materials — so the interface does not crack when the device cycles. That combination is why diamond powder is being specified as a functional filler rather than an abrasive: into diamond/Cu and diamond/Al heat spreaders, into diamond-reinforced SiC, and into thermal interface materials.
We supply the powder for all three routes. Titanium-coated grades for metal-matrix work, high-purity uncoated grades where the matrix is a polymer, and multi-modal size blends where the customer is chasing maximum filler loading.
Why coating decides the result
Bare diamond does not wet to copper or aluminium. The interface is mechanically weak and full of gaps, and the thermal resistance you removed from the die comes back at the boundary. A titanium layer gives the metal something to bond to, forms a continuous conduction path and suppresses thermal damage to the diamond surface during sintering. Where the matrix is a polymer or a gel, uncoated high-purity powder usually performs better and costs less, so the coating choice follows the process, not the brochure.
Spherical, coated and high-purity grades
Spherical diamond has a high specific surface area and packs densely, which reduces voids between particles and lowers interfacial thermal resistance. It is the grade most often requested for thermal gels and pads. High-purity material is produced to reduce non-diamond carbon, nitrogen and metallic inclusions — relevant because metal contamination in a TIM or a semiconductor-adjacent part is a reliability problem, not just a datasheet number. Boron-doped diamond is available for electrochemical and electrode work but is not a thermal filler.
Recommended Grades And Size Ranges
Sizes below are the ranges our thermal-management customers actually order. Titanium-coated grades cover the metal-matrix routes; uncoated high-purity grades cover polymer, gel and SiC work.
| Route | Recommended grade | Size range | Why this grade |
|---|---|---|---|
| Diamond-Cu / diamond-Al heat sinksChip heat spreaders, IGBT modules, RF devices | |||
| Metal matrix composite (MMC) | Ti-coated HDY micron, Ti-coated MBD / SMD | 4–8 µm, 8–16 µm, 10–20 µm, 30–40 µm, 36–54 µm, 80/100 – 270/325 mesh | Coating bonds the particle to the metal matrix |
| 3D printed copper-diamond | Ti-coated HDY | 30–40 mesh, 36–54 mesh, 40–60 mesh | Coarse, regular particles for powder-bed feedstock |
| Diamond-SiC compositesLow expansion, high conductivity, wear parts | |||
| SiC-based heat spreader | Ti-coated HDY, or uncoated HDY by process | 4–8 µm, 8–16 µm, 10–20 µm, 36–54 mesh | Graded to match the SiC matrix |
| Thermal interface materialsGrease, gel and pad formulations | |||
| TIM filler | HDY monocrystalline micron, Ni or Ti coated on request | 0.5 µm, 1 µm, 1–100 µm multi-modal blends | Blend ratio drives filler loading |
| Spherical filler | MBDS spherical diamond | 80/100 – 270/325 mesh, 0–2 µm | Round shape packs denser, fewer voids |
Total supply window for these grades is 50 nm to 600 µm. Tell us the matrix, the process temperature and the target conductivity; we will recommend a single-grade or multi-modal solution and send a sample against your formulation.
What has to hold
- Coating uniformity and completeness
- Tight particle size distribution
- High thermal conductivity
- Good interfacial bonding
Where it ships
Diamond Grades For This Process
Factory Direct Since 1990
Zhecheng Hongxiang Superhard Material Co., Ltd. is an integrated manufacturer and exporter of synthetic diamond powders since 1990, located in the Diamond Capital of China.
- Own manufacturing base in Zhengzhou, Henan — powder, coating and grading on one site.
- In-house particle size and SEM inspection on every batch before packing.
- Export packing with neutral or custom label, plus sample quantities for process trials.
What To Include
Describe your workpiece, process and target result. We will match the diamond grade from the existing product range.