Flake Graphite for Powder Metallurgy — Technical Benefits & Typical PM Applications

Following the 7th Asian Powder Metallurgy Conference recently held in Qingdao, industry leaders reinforced the value of tailored additives in PM formulations. Natural flake graphite powder remains a high-impact, low-complexity additive that delivers measurable improvements in pressing, sintering and in-service performance across a wide range of PM products.

Technical Roles — What Flake Graphite Does in PM

1. Solid lubrication during compaction — Flake graphite reduces inter-particle and powder/tooling friction, enabling higher green density at the same compaction pressure, smoother ejection, and lower die wear.

   
   

2. Sintering aid & controlled carbon source — Properly specified graphite contributes carbon in a controlled way to achieve the target microstructure (pearlite/ferrite balance), supporting uniform densification and metallurgical consistency.

   
   

3. Porosity management & wear performance — Graphite affects pore connectivity and microstructure evolution; optimized additions reduce residual porosity and increase wear resistance for teeth, bearing surfaces and bushings.

   
   

4. Surface finish & dimensional stability — The flake morphology helps form thin lubricating films in green compacts, improving surface finish and dimensional repeatability after sintering and finishing.

   
   

Typical PM Products & Benefits 

• Transmission gears: improved die fill, higher sintered density, better tooth wear life.

• Dampers / shock-absorbing components: controlled porosity for stable damping characteristics.

• Bearings & bushings: reduced friction, extended service intervals.

• Structural parts (brackets, links): more consistent mechanical properties, improved dimensional stability.

• Valve bodies & hydraulic components: cleaner sintered surfaces and better sealing.

• EV drivetrain parts: tight tolerances and improved wear resistance for high-duty cycles.

  
  

Practical Guidelines (starting points)

• Particle size (typical PM grades): ~44–75 µm (200–325 mesh). Use finer fractions (<20 µm) for ultra-high density parts.

• Addition rate: 0.2–1.5 wt% (common precision gears: 0.5–1.0 wt%). Validate in lab trials.

• Purity: choose low ash (<1%) and low sulfur grades to avoid contamination and embrittlement.

• Morphology: flake form to enhance lubrication; consider blending with finer amorphous fractions if dispersion issues occur.

  
  

Integration Notes & Best Practices

• Check compatibility with pressing lubricants (e.g., zinc stearate) — graphite can reduce external lubricant needs but may alter ejection forces.

• Use controlled mixing (V-blender, Turbula) for homogeneous dispersion.

• Adjust sintering atmosphere (H₂, vacuum, dissociated NH₃) and hold profiles to balance carbon pickup and oxide reduction.

  
  

Why Qingdao Xinghe Graphite

• Custom milling & screening to match your PM recipes.

• Strict chemical control (fixed carbon, low ash, low S) for predictable metallurgy.

• Technical support: datasheets, sample kits, lab trials, and on-site assistance.

• Reliable inventory and logistics to support pilot runs and production orders.

• Compliance Support: We assist in preparing documentation for legitimate civilian applications that require regulatory approvals.

  
  

Call to Action

Request a PM sample kit and technical datasheet to optimize your formulations for gears, dampers, bearings, and structural PM parts.

Contact: John#xhgraphite.com | www.graphitezone.com | +86-18663987730