For designers looking to manufacture burr and stress-free metal parts with complex geometries, maintain the flexibility to make last-minute design changes and produce prototypes quickly, photochemical etching is the answer.
This versatile sheet-metal-machining technology uses photoresists and etchants to selectively remove areas of the sheet with accuracy to }0.025mm.
Working from easily reiterated and low-cost digital tooling, the technology provides a cost-effective, validationfree, highly accurate and speedy manufacturing alternative to traditional machining technologies.
Overcoming the difficulty of titanium etching
Precision Micro can apply the process to almost any metal – even those notoriously difficult to machine.
Titanium and its alloys are favoured by medical designers due to their lightweight, strength and biocompatibility. However, these properties prove to be a challenge when machining, with titanium's hardness often resulting in reduced tool life or slower speed of cut.
The use of photo-etching overcomes these issues, but even etching titanium is difficult as the metal forms a protective oxidised coating when exposed to air, meaning it cannot be etched with standard etch chemistries.
To overcome this, Precision Micro has developed a proprietary process, investing in specialist equipment and process chemistry to produce etched parts comparable in quality to those produced in more conventional medical-grade materials, such as 316 stainless steel.
Craniomaxillofacial implants
Biocompatible cranial and dental implants can be extremely featuredense, and demand burr-free edges that traditional machining technologies find difficult to achieve.
Etched implants benefit from zero thermal distortion and burr-free openings. Complex, accurate aperture arrays and countersinks can be included at no additional cost, removing the need for additional machining.
Cardiac rhythm management
Precision Micro manufactures intricate, 0.075mm titanium anode and cathode battery current collector grids used in lithium batteries contained within implantable defibrillators, ensuring a reliable energy supply from a smaller footprint. The company also manufactures micro-pacemaker screening cans, which feature an electrical insulator selectively applied to reduce arcing.
Orthopaedic saw blades
Typically, sharp-toothed blades are profiled using laser-cutting before grinding to achieve the required tooth offset. By using the depth-etching technique, one of the world-leading medical OEMs partnered with Precision Micro to develop a unique tooth profile that removed the need for the secondary grinding operation.
Today, Precision Micro supplies thousands of sagittal and oscillating bone saws each month, machined to }0.005mm – impossible with laser-cutting and grinding.
Medical electronics
A wide range of 2D and 3D electronics components, including lead frames, EMI/RFI shielding, connectors, contacts, biosensor springs and meshes, can be photo-etched burr and stress-free, with clean profiles and no heat affect.
In 2019, Precision Micro secured ISO 13485, making it one of a small number of photo-etching suppliers to hold the stringent medical device standard and the only accredited etching supplier in Europe.
With over 50 years' experience as a photo-etching specialist, Precision Micro's continual investment in chemical etchants and process parameters means that, today, even the most challenging metals can be processed with high levels of accuracy and repeatability.
