1. Feasible Processing Methods for Embossed 3D Characters
Process: Custom stamping dies are made according to the character design; the weathering steel plate is pressed at room temperature or slightly heated (150–200°C) to form raised 3D characters.
Applicability: Ideal for signs with character depth of 2–10 mm and large production volumes (e.g., highway scenic signs, corporate logos).
Key Note: Hot-rolled weathering steel plates (thickness 3–8 mm) are preferred-their higher ductility avoids cracking during stamping; cold-rolled plates (≤3 mm) are suitable for shallow embossing (≤2 mm) but require stress relief annealing beforehand to reduce residual stress.
Process: Cut individual 3D characters from weathering steel plates, then weld them onto the sign panel base at a specified height (5–20 mm).
Applicability: Perfect for personalized designs, complex fonts, or small-batch orders (e.g., art installation signs, boutique store logos).
Key Note: Use matching weathering steel welding electrodes (e.g., E7018-C1) to ensure the weld zone has the same corrosion resistance as the base metal; grind the weld seams smooth to avoid uneven patina formation.
Process: The steel plate is clamped and formed using high-pressure water to create embossed characters on curved or irregular sign surfaces.
Applicability: Suitable for architectural facade signs with curved contours; minimal surface damage ensures uniform patina growth.
2. Key Considerations for Patina Uniformity on Embossed 3D Characters
Pre-Treatment Uniformity: Sandblast the entire sign panel (including embossed characters) to create a uniform surface roughness (Ra 3–5 μm); remove oil stains and stamping residues to eliminate oxidation "starting point differences".
Artificial Patina Acceleration: Apply a uniform layer of chemical accelerator to the entire panel; place it in a controlled humidity chamber (70–90% RH, 20–30°C) for 3–5 days. The raised character edges will oxidize slightly faster, so adjust the curing time to balance color consistency.
Post-Patina Sealing: Coat the entire sign with a transparent breathable fluorocarbon sealant after patina maturation-this locks in the uniform color and prevents differential oxidation caused by rainwater runoff on 3D characters.
3. Advantages of Embossed 3D Characters on Weathering Steel Signs
Aesthetic Uniqueness: The raised 3D characters cast subtle shadows under sunlight, enhancing visual hierarchy; the natural patina color (reddish-brown) gives the sign a rustic, high-end look that blends with outdoor environments.
Durability: No need for painting or plating- the protective patina layer resists corrosion, and the embossed structure has high mechanical strength to withstand wind, rain, and UV exposure.
Low Maintenance: Only requires annual rinsing with clean water to remove dust; the patina self-heals minor scratches on character edges over time.
