The wire polishing/sanding technique is like the “light and shadow poet” of stainless steel jewelry, expressing the sensuous touch within the rational texture.
When mirror-polishing aims for the ultimate reflection, the wire brushing and frosted finishes are meticulously crafting the dance of light. They impart an understated and profound quality to stainless steel jewelry through directional textures or uniform matte finishes. This is not merely a “satin treatment”, but rather through precisely controlled surface micro-engraving technology, it creates a dual poem of touch and vision on the metal surface, elevating industrial rationality to a sensuous aesthetic.
Precise control of linear light tracks
By performing single-direction grinding on the surface to form continuous parallel micro-grooves, light undergoes directional reflection at the edges of the grooves, resulting in a silky smooth luster.
Straight Grain: The texture is parallel to the long side, enhancing the sense of longitudinal extension.
Radial Grain: Radiating texture surrounding the center point, used for ring bands and dial plates.
Cross Grain: Double-angle (usually 45°) interlacing, forming a micro-pyramid structure, improving wear resistance.
Satin/Matte finish is the softening art of light.
It creates a uniform and disorderly surface of tiny depressions, causing light to undergo multi-directional scattering and presenting a velvet-like texture.
Mechanical sandblasting creates physical texture through sandblasting or grinding.
Chemical sandblasting uses an acid-etching solution to selectively dissolve the grain boundaries, forming a microporous structure (more fine-grained but with higher environmental requirements).
The laser wire drawing technology of Schaffner Company in Germany can create parallel nano-level grooves with a width of 0.05mm and a depth of 0.01mm on the surface through femtosecond laser pulses (Ra = 0.03μm). This completely eliminates the edge burrs problem of traditional mechanical wire drawing.
Selection of abrasive materials for sandblasting:
Glass beads (GB): Produce a frosted effect, Ra 0.8 – 1.5 μm
Aluminum oxide (Al₂O₃): Coarser granular texture, Ra 1.5 – 3.5 μm
Silicon carbide (SiC): Ultra-fine matte finish, Ra 0.4 – 0.8 μm
Chemical polishing (Acid Etching) formula: HNO₃ (15%) + HF (2%) + H₂O₂ (5%), at a temperature of 40℃
Time: 30 – 120 seconds (for every 30-second extension, Ra increases by 0.1 μm)
The matte finish can reduce the visibility of minor scratches (depth ≤ 5 μm) by 80% (compared after the ASTM B117 salt spray test).
The cross-scratched texture can completely conceal flaws with a depth of ≤ 10 μm, and the maintenance cost is less than one-third of that of a mirror finish.
Helas process: After preheating at 250℃, the wire is drawn, and the edge of the groove undergoes a slight oxidation coloring, achieving a gradual purple-gray sheen effect.
Parametric texture generation, using the Femap software to simulate the propagation path of light on the preset texture, to generate the 3D microstructure with the best optical effect (such as: anti-fingerprint rhombic array)
Robot adaptive polishing, with the ABB robotic arm equipped with the force control abrasive belt module, real-time feedback on surface roughness (online white light interferometer), and dynamic adjustment of pressure and speed (tolerance ±2N, ±0.1m/min)
Nano-coated composite texture: First, a mechanical sanding base with Ra = 0.6 μm is fabricated. Then, an AF nano-coating is deposited by gas-phase deposition (contact angle > 110°) to achieve an anti-fouling matte surface (suitable for luxury wristwatches)
The wire drawing and matte finishing techniques, this art that directs light at the 0.1 micrometer scale, transforms cold metal into a warm tactile language. When the fingertips glide over the delicate silk-like lines, and when the gaze delves into the soft-blurred matte depths, the most primitive sensory experience of humanity and the most precise industrial control merge here.
This is not merely a surface treatment; it is a sensory revolution for metals – it channels the river of light through directional grooves and weaves a mist of light with uniform indentations. In the dance between intelligent technology and artisanal experience, the texture aesthetics of stainless steel jewelry are entering a new era: every line is calculable, and every touchable part can be designed.
When the wearer rotates the braided bracelet on their wrist, the light flows through the grooves like strings of silk; when the frosted surface of the ring glides across the fingertips, the velvety touch gently caresses the skin – this is the metal verse written by the fusion of industry and art. Here, reason and emotion no longer oppose each other; they have reached an eternal reconciliation in the microscopic texture universe.
