ForMatter/Finishes/anodize/Black anodize (dyed Type II)
finish_anodize_black_dyed

Black anodize (dyed Type II)

anodize · colored · dyed black anodize, MIL-A-8625 Type II Class 2 black

Same Type II oxide layer, but soaked in organic dye between the bath and the seal. The porous fresh oxide drinks the dye in; the seal locks it. Black-anodized lens barrels, rifle handguards, GoPro housings, MacBook keyboard frames.

Type II Class 2 per MIL-A-8625 — anodize bath, then immersion in dye solution (~5 g/L organic dye, 60 °C, 10–15 min) before nickel-acetate seal. Color depth depends on oxide thickness; black needs ≥10 µm to read truly opaque. Grade-A dyes (Sandoz, Clariant) UV-stable for outdoor service. Cheap dyes fade in sun within months. Substrate alloy matters — 6061 / 6063 dye uniformly; high-copper 2024 / 7075 streak warm-brown without careful chemistry.

character — deep matte to satin black, soft, pen-stroke even on flat areas, the modern-tech default.

Finish properties

  • levelcolored
  • subcategoryType II sulfuric acid + organic dye
  • Ra (µm)0.6
  • applies tometal
Produced by processesAnodizing

Second life

reversibilitymoderate — the oxide layer can be stripped chemically (NaOH bath) and re-anodized. Color is permanent unless stripped; reversal requires controlled chemistry.
blocks substrate recyclingno
renewabilityshop-renewable — strip and re-anodize at any anodizing-shop with the matching color bath. Field-renewability is zero (you cannot anodize on a job site).

Aluminum Anodizers Council technical bulletins; ASTM B580 anodic-coating standard.

Citations