Post-processing tips for 3D printing: Polishing technology achieves a surface roughness of Ra0.1μm for parts.

I. Polishing Process: The Core of Improving Surface Precision for 3D Printed Parts

The surface quality of 3D printed parts directly affects the product's sealing, wear resistance, and aesthetics, and polishing is the core means of improving surface precision in post-processing. Parts produced by different 3D printing technologies (such as SLM metal printing and SLA photopolymerization printing) require different polishing processes due to differences in material properties and forming principles.

For example, metal 3D printed parts often have oxide scale and interlayer textures, requiring specific polishing solutions; photopolymerized parts often have resin residue and micro-burrs, making fine-tuning the polishing process crucial. Achieving a high-precision polishing finish of Ra 0.1μm cannot be accomplished with a single process; it requires comprehensive control over the entire process, including pre-treatment, core polishing, and post-cleaning.

II. Pre-treatment: The Foundation for High-Precision Polishing

The pre-treatment stage is the foundation for high-precision polishing. First, the 3D printed product undergoes visual inspection, marking the locations of defects such as protrusions, burrs, and layer lines. Then, surface impurities are removed according to material characteristics. For metal parts, sandblasting can be used to initially smooth the surface, removing oxide layers and adhering powder.

Sandblasting pressure should be controlled at 0.3-0.5MPa to avoid damaging the substrate. For photocured parts, uncured resin must first be removed by ultrasonic cleaning with alcohol, followed by drying and then light sanding to remove burrs. The surface roughness of the pretreated parts must be controlled within Ra 3.2μm to lay the foundation for subsequent high-precision polishing.

III. Core Polishing Process Selection and Parameter Optimization: Overcoming the Key to Ra 0.1μm Accuracy

The scientific selection and parameter optimization of the core polishing process are key to achieving Ra 0.1μm accuracy. For different materials, mainstream high-precision polishing solutions can be divided into three categories:

First, for metal parts (such as titanium alloys and stainless steel), a combination of mechanical polishing and electrolytic polishing is suitable. Mechanical polishing uses diamond polishing paste (1-3μm particle size) for fine grinding, followed by electrolytic polishing to optimize the surface micro-structure. The electrolytic voltage is controlled at 12-15V and the temperature at 25-30℃, which can effectively reduce the surface roughness to Ra0.1μm.

Second, for resin parts, high-pressure water jet polishing combined with manual fine polishing is recommended. The high-pressure water jet pressure is set at 50-80MPa to precisely flush out tiny surface depressions, followed by manual finishing with chromium oxide polishing paste, balancing efficiency and precision.

Third, for ceramic matrix composites, chemical mechanical polishing is used. Through the synergistic effect of silicon oxide abrasive and chemical corrosion, cracks caused by mechanical grinding are avoided, achieving high-precision flatness.

IV. Post-cleaning and Inspection: Ensuring Precision Standards and Product Durability

The post-polishing cleaning and inspection process is crucial. After polishing, residual polishing paste, abrasives, and chemicals on the surface of the parts must be removed promptly. Metal parts can be ultrasonically cleaned with acetone, and resin parts can be wiped with isopropanol to ensure no impurities remain on the surface.

Subsequently, a surface roughness meter is used to accurately measure the surface roughness, focusing on complex areas such as cavities and corners, ensuring that the entire area meets the Ra0.1μm standard. Furthermore, depending on the intended use of the parts, rust prevention treatment and coating protection can be added after polishing to further extend the product's lifespan.

V. Summary and Outlook: High-Precision Polishing Drives High-End Applications of 3D Printing

High-precision polishing is the core support for achieving high-end applications of 3D printed parts. Through meticulous control of the entire process—pre-treatment, core polishing, and post-cleaning—a surface accuracy of Ra0.1μm can be stably achieved.

In actual production, Pans selects polishing solutions tailored to the printing materials and product structure, while also focusing on iterative optimization of process parameters. In the future, with the integration of automated polishing equipment and intelligent detection technology, the efficiency and accuracy of 3D printing post-processing will be further improved, driving the deep application of 3D printing technology in more high-precision fields.