By Ruijin CNC作者：锐金峰汇Sep 02, 20262026年9月2日Finish表面处理
Anodizing is an electrochemical process that grows a durable oxide layer on aluminum, dramatically improving corrosion resistance, hardness and appearance. It is the default finish for most machined aluminum parts.
Anodizing builds a hard oxide layer on aluminum — Type II for decorative, Type III (hardcoat) for wear surfaces.阳极氧化在铝表面形成氧化膜——Type II 装饰用，Type III（硬质）耐磨。
How Anodizing Works
The aluminum part is submerged in an acid bath and connected as the anode. An electric current grows a controlled oxide layer that bonds with the surface at the molecular level.
Type II vs Type III
Type II (sulfuric) anodizing is the standard decorative finish, offering a range of colors. Type III (hardcoat) produces a much thicker, harder layer for wear resistance in demanding applications.
Type II offers broad color options (black, red, blue, gold) via dye absorption before sealing.Type II 在封孔前通过染色吸附实现多种颜色（黑、红、蓝、金）。
Color Options
Natural (clear), black, gold, red, blue, green and custom colors are all achievable. Dyes are absorbed into the porous oxide layer before sealing, producing uniform, durable color.
Benefits for Machined Parts
Anodizing improves corrosion and scratch resistance, provides electrical insulation, and enhances aesthetics. It does not peel or flake because the layer is grown from the metal itself.
Type III hardcoat delivers 60–70 Rockwell C surface hardness — ideal for high-wear sliding or impact parts.Type III 硬质氧化可达 60–70 HRC 表面硬度，适合高磨损滑动或冲击件。
Design Tips
Mask threaded holes and tight-tolerance surfaces if they must not be coated. Be aware anodizing adds a small, predictable thickness that can affect press fits.
Need a anodized part? Send your drawing for a free DFM review and a quote within 24 hours.
Anodizing builds a hard oxide layer on aluminum — Type II for decorative, Type III (hardcoat) for wear surfaces.阳极氧化在铝表面形成氧化膜——Type II 装饰用，Type III（硬质）耐磨。
阳极氧化原理
铝件浸入酸性电解液并接阳极，电流生长出受控的氧化层，在分子层面与表面结合。
Type II vs Type III
Type II（硫酸）阳极氧化是标准装饰处理，颜色丰富；Type III（硬质）阳极氧化层更厚更硬，用于高耐磨场合。
Type II offers broad color options (black, red, blue, gold) via dye absorption before sealing.Type II 在封孔前通过染色吸附实现多种颜色（黑、红、蓝、金）。
