What surface finishes are recommended for reducing gear wear?
What Surface Finishes Are Recommended for Reducing Gear Wear?
Role of Surface Finish in Gear Longevity
Surface finish directly impacts gear efficiency, noise, and wear rate. In precision die cast gears—especially those made from brass alloys like C85800 or C87850—controlling surface roughness and applying wear-resistant coatings can significantly extend service life and improve gear meshing accuracy. At Neway Die Casting, we apply a combination of post-machining and coating techniques to enhance gear surface durability.
Recommended Surface Finishes for Gear Applications
Polishing and Superfinishing
Mechanical polishing or vibratory tumbling is applied to reduce surface roughness and eliminate micro-asperities that initiate wear.
Achievable roughness: Ra 0.2–0.6 µm
Benefits: Lower friction, smoother engagement, reduced noise
Best for: Small worm gears, fine-tooth spur gears, and high-speed rotary systems
Electroless Nickel Plating
A uniform, hard coating that enhances wear resistance while maintaining dimensional stability.
Hardness: 500–700 HV (as-deposited)
Thickness: 8–25 µm
Conforms to ASTM B733 and ISO 4527
Ideal for: Gears in humid or lubricated environments requiring abrasion protection
Phosphating (Zinc or Manganese)
Used on ferrous gear components but occasionally applied to brass for improved surface interaction in mixed-material systems.
Increases surface hardness and oil retention
Improves break-in and load-bearing wear resistance
Best for: Gear sets operating under high load and intermittent lubrication
Teflon or PTFE Coating
Non-metallic coatings that provide dry-lubrication characteristics for low-load, high-frequency gear sets.
Reduces friction coefficient (down to 0.05)
Applied via spray coating over machined surfaces
Suitable for: Quiet-running plastic-brass hybrid gears and actuator systems
Surface Finish Selection by Gear Type
Gear Type | Recommended Finish | Key Benefit |
|---|---|---|
Worm Gears | Polishing + Electroless Nickel | Reduced sliding wear, smooth meshing |
Spur Gears | Polishing | Lower friction and gear noise |
Planetary Gears | Electroless Nickel | Uniform hardness and wear resistance |
Micro Actuator Gears | PTFE Coating | Dry lubrication, reduced stiction |
Quality and Surface Control
Neway controls and validates gear surface finishes using:
Surface profilometry (Ra, Rz)
Cross-section coating thickness measurement
Adhesion testing per ISO 2409
Run-in simulation and accelerated wear testing for high-cycle gears
Customer-Oriented Gear Finishing Solutions
Neway Die Casting provides high-performance surface finishing tailored to gear functionality:
Post-Machining Services: Precision surface refinement and tooth flank finishing
Surface Finishing: Polishing, nickel plating, and wear-resistant coating application
Brass Die Casting: Stable casting base for high-finish, high-precision gear parts
