What are the surface treatment processes for 3D printed titanium rods?

The main surface treatment processes for 3D printed titanium rods include the following, aimed at improving their surface quality, mechanical properties, and functionality:

I. Mechanical Polishing

1. Sandblasting: Uses abrasives such as Al₂O₃ or glass beads to uniformly roughen the surface; suitable for preliminary treatment.

2. Vibration/Magnetic Polishing: Suitable for small parts or complex structures, effectively improving surface finish.

3. CNC Finishing: Milling or turning high-precision mating surfaces to ensure dimensional tolerances. 3D Printing Titanium / Gr5 Titanium Bar / Ti 7Al-4Mo Titanium Bar

II. Chemical and Electrochemical Polishing

1. Chemical Polishing: Smooths the surface through chemical dissolution, especially suitable for porous structures or complex internal cavities, reducing roughness from 6–12 μm to 0.2–1 μm.

2. Electrolytic Polishing: Significantly improves surface finish and removes surface oxides for stainless steel and titanium alloys.

III. Advanced Processes

**Shape-Adaptive Grinding:** Uses flexible grinding heads to polish free-form surfaces, achieving surface roughness below 10nm.

**Abrasive Flow Machining:** Polishes hard-to-reach areas such as internal surfaces and cavities using viscous abrasive fluids.

**Laser Polishing:** Utilizes high-energy lasers to melt surfaces, achieving roughness of 2–3μm, but with higher equipment costs.

III. Functional Treatments

**Anodizing:** Forms an oxide film on titanium surfaces, enhancing corrosion resistance, hardness, and insulation; can also be colored.

**Phosphating:** Used as a pretreatment before coating, improving coating adhesion and corrosion resistance.

**Blackening:** Generates an oxide film for rust prevention; commonly used for low-carbon steel, but titanium alloys require specific processes.

IV. Other Technologies

**Hot Isostatic Pressing:** Seals internal pores, increasing density; suitable for high-requirement components.

**Coatings/Plates:** Such as PVD coatings and anodizing to enhance wear resistance or corrosion resistance.