Etched metal plate refers to flat thin metal panels processed by photochemical etching (chemical etching). Using photoresist masking and controlled chemical spray etching, selective material removal is performed on metal sheets to form customized patterns, micro flow channels, dense hole arrays, slots and outer contours. Both through-etch and half-etch options are available to meet different functional requirements.

A wide range of metal materials can be manufactured into etched metal plates: stainless steel, copper, phosphor bronze, Kovar, nickel, molybdenum, titanium, nitinol and other specialty alloys. Typical etched metal plates include fuel cell bipolar plates, shadow masks, encoder discs, filter plates, EMI shielding panels, precision shim plates and decorative etched nameplates.

Etching Workflow

1. Material Pre-treatment: Raw metal plate undergoes degreasing, oxide removal and full rinsing. Surface contaminants are eliminated to avoid pinholes, discoloration and pattern defects.
2. Photoresist Lamination: Dry film photoresist is laminated on one or both sides of the metal plate to form a protective mask layer.
3. UV Exposure & Development: Custom CAD patterns are transferred onto photoresist by double-sided UV exposure. Un-exposed resist is washed away to expose metal regions for etching.
4. Controlled Spray Etching: The plate passes through automated conveyor spray etching system. Etchant temperature, concentration and spray pressure are strictly stabilized. Half-etch for surface grooves or full through-etch for perforated plates can be realized.
5. Resist Stripping & Cleaning: Remaining photoresist is stripped by alkaline solution, followed by multi-stage rinsing and air drying to eliminate chemical residues.
6. Inspection & Post-processing: Flatness, depth and dimensional inspection. Optional secondary operations include conductive coating, passivation, plating and surface finishing.

Core Advantages

• Burr-free and zero residual stress: No stamping or cutting force, the metal plate remains flat without microcracks or deformation.
• High pattern complexity: Capable of producing dense micro holes, continuous curved flow channels and intricate interlaced structures that stamping hardly achieves.
• Flexible customization: No expensive hard die. Design revision can be completed quickly for prototype and small batch verification.
• Uniform etch depth: Consistent feature dimension across the whole plate surface, ideal for large-area panel components.
• No heat-affected zone: The chemical process does not alter metal intrinsic mechanical and electrical properties.
• Smooth inner surface: Low roughness for fluid channel and gas distribution applications.

Application Fields

• Hydrogen energy: Fuel cell metal bipolar plates with micro flow channels
• Semiconductor industry: Shadow masks, metal mask plates, packaging carrier plates
• Precision sensing: Encoder code plates, optical grating plates
• Filtration industry: Perforated filter plates and micro-hole metal filter panels
• Electronics: EMI shielding plates, spring contact plates, custom lead frame panels
• Industrial & medical: Precision spacer plates, medical filter plates, engraved nameplates

Design & Process Notes

1. Feature width must follow photochemical etching design rules, the minimum feature size correlates with plate thickness.
2. Side undercut should be calculated in the design phase to guarantee final dimensional accuracy.
3. Half-etch design is widely adopted for recessed micro channels without penetrating the plate.
4. Thin etched metal plates need proper fixture and handling during production to prevent warpage.
5. For corrosion and conductive requirement, surface coating or passivation treatment is recommended after etching.