Photochemical Machining & Photochemical Etching

Tecomet Inc. specializes in aluminium photochemical machining using photochemical etching to precisely etch small thin metal parts to your specific application. Tecomet Inc. offers this photochemical etching service with an expansive variety of photochemical etching materials.

Tecomet Inc. Process

When starting photochemical machining, thin metal sheets are cleaned with chemical solutions and laminated with a very thin layer of photo-resist film. Using a CAD created Photo-Tool, images are printed on both sides of the sheet using calibrated Ultra Violet lights.

Printed sheets are developed in chemical solutions to expose the metal surface in the printed areas. The sheets are then sprayed with proprietary solutions so that the exposed metal dissolves away. The photoresist film used in the photo chemical etching process protects the material in the areas that were not washed away in the developing process. After etching, the residual photoresist film is stripped in alkaline solutions. Process parameters at each stage are controlled to obtain the desired dimensions and finish. Upon completing a dimensional and visual inspection, components are ready for any necessary secondary operations such as forming, plating, heat-setting, passivation, anodizing, and more.

Dimensional Accuracy

Dimensional accuracy is a function of metal thickness. Better accuracies, finer features, and tighter tolerances can be achieved on thinner metals. Another significant factor is the type of metal and how it is affected by the etching solution. For example, aluminum etches at a significantly faster rate than stainless steel. Titanium etching requires a different etching chemistry than stainless steel or copper etching.

Photo-Tool and Etch-Allowance

A CAD drawing of the component is used to design a photo-tool used in the photo chemical machining process. Adjustments are made to the external and internal dimensions based on type and thickness of the metal to be etched. A layout of the photo-tool is prepared, incorporating the proper etch allowance. The layout is comprised of placing many components on a sheet to effectively utilize the surface area. Using an extremely high resolution laser printer the layout is printed on transparent mylar sheets. The photo-tool is ready for use when the top and bottom mylar sheets are aligned and registered. In cases where ultra high resolution is needed, a glass tool is used instead of mylar.

Advantages of Tecomet Services

• - High Quality at Competitive Prices
• - Medical Device Experience – CE/FDA Approved Devices
• - Nitinol: First Company to Successfully Etch Nitinol and Continue to Lead the Industry
• - Fast Turnaround: Standard Lead Time is 2 Weeks, but Expedited Delivery can be as fast as 2-3 Days
• - Quality: ISO Certified Since 2003. Automated Visual Inspection Systems are used for Measuring Tight Tolerances
• - ITAR: Registered and Compliant
• - R&D to project launch capabilities
• - Thin Foils: Routinely Etch Metals <0.001” Thick (<25 um)

Advantages of Metal Etching

• - Precise, Quick, Economic and Flexible
• - Cuts Metal Clean & Burr Free
• - No Heat-Affected Zones, Dross, or Striations
• - Short Engineering Design Cycle
• - Low Tooling Cost
• - Etched Parts can be formed, shape-set, plated or finished
• - Cost-effective at high-volume productions

Metals Etched

• - Stainless Steel Alloys
• - Copper Alloys
• - Nitinol
• - Titanium 
• - Aluminum
• - Cobalt-Chromium Alloys (Co-Cr)
• - Molybedenum
• - Nickel-Silver Alloys (Ni-Ag)
• - Kovar/Invar
• - Inconel
• - Hy-Mu 80

Typical Chemically Etched Products

• - Shields and Fences
• - Medical Devices and Components
• - Electrical Contacts
• - Shims
• - Filters
• - Springs
• - Carriers