additive.tools
All tools

Electropolishing Time-to-Ra Estimator

Universal

Estimate wet-electropolishing time, material removal depth, and achievable Ra on LPBF and DED metal parts. Covers stainless steel, titanium, cobalt-chrome, nickel superalloys, and aluminium. Ra decay modelled as an exponential approach to a material-specific floor roughness.

Sign up to use this calculator

additive.tools is a membership platform for AM engineers. Sign up free to unlock 11 calculators plus the full materials & process knowledge base. Pro tier unlocks all 44 tools.

  • 11 free calculators (44 total on Pro)
  • 46-material property knowledge base
  • Save your calculations to your profile
  • No credit card · no marketing emails
Create your accountI have an account

Ra decay model

Ra(d) = Ra_f + (Ra₀ − Ra_f) · e^(−d / λ)
Ra(d)
Surface roughness after removal depth d[µm]
Ra₀
Initial as-built roughness[µm]
Ra_f
Electro-finishing floor roughness[µm]
d
Cumulative material removal depth[µm]
λ
Characteristic decay length (material-dependent)[µm]

Exponential decay model consistent with published EP data for LPBF stainless (Ra₀ ≈ 6–12 µm → Ra_f ≈ 0.2–0.6 µm). Current density shifts the effective λ.

Process notes

Medical and implant parts

Electropolishing is the preferred final step for 316L and CoCrMo implants — removes the recast layer, improves corrosion resistance, and achieves Ra < 0.8 µm typically required by ISO 13485 quality systems.

Titanium electrolyte

Ti-6Al-4V requires a specialist electrolyte (perchloric/acetic or fluoride-based). Standard stainless EP baths do not work. Consult the electrolyte supplier for current-density limits and bath life.

Sources