Q&A: The uses of etching in medical device manufacturing

Gary Marriot, technical sales manager for Advanced Chemical Etching Ltd (ACE), explains to Med-Tech Innovation News the uses of etching in the manufacture of medical devices. 

For those that don’t know, tell us about ACE?

Located in the heart of the UK, Advanced Chemical Etching Ltd (ACE) uses innovative chemi etching processes to manufacture precision metal components from prototypes to volume, providing today’s product development engineers greater flexibility in design and shorter lead times. ACE is the leader in innovative metal etching in the UK and supplies many sectors with precision metal etching– making the difference in innovation, technology and manufacturing.

Tell us about your etching process, what is different about it?

While etching is conventionally viewed as a ‘black art’ where methods evolve through experience and trial and error, ACE has adopted a much more systematic approach based on scientific research.

Several of the steps involved in the etching process are chemical in nature, so a fundamental understanding of the chemical phenomena that occur in these processes is important. This is why ACE has invested heavily in Research & Development over the past ten years and our new unique and innovative aluminium and titanium etching process is a testament to the power of this approach.

Can you give us a simple step-by-step guide of the process for us?  

Photo etching is the process of using ultra-violet light to fix an image onto a sheet of metal through a low-cost digital tool, and then using chemicals (etching solution) to etch the shape into the metal, removing more and more of the material until only the shape is left – a metal component that is far more precise than anything that can be cut or machined. Photo etching is a very precise method of metal cutting and etching to produce designs on flat sheets of metal with thicknesses up to 2.5mm. Due to the nature of this process, it is possible to photo etch parts with an unrivalled level of complexity, incorporating special features, in most metals, with thicknesses ranging from 5 μm to 2.5mm. The resultant components produced by precision chemical etching are stress-free with no burrs or rough edges and with no changes to the original material properties.

How long has it taken you to evolve the process to what it is now? 

Working closely with Academia, and adopting a scientific approach, since its inception in 2000 we are constantly reviewing our capabilities in line with industry needs. Utilising our fully equipped in house laboratory we are able to investigate the possibility of etching previously difficult to etch materials utilising XRF based research to investigate down to the molecular level for both material and chemistry.

How important is this process to the medical device industry?

Advances in the medical sector are progressing rapidly and many companies are being left behind in the pursuit for cutting-edge products.

This has created many new challenges, not least in the increase in demand for titanium and titanium alloys used for medical implants and cathode grids used in pacemaker batteries.

Titanium is renowned for its strength and lightweight properties, but it is difficult to etch due to it rapidly forming a protective oxidised coating when exposed to air. Traditionally, Hydrofluoric Acid (HF) and Nitric mix has been used as the preferred etchant, but it is a highly dangerous and toxic material and one we are not keen to use.

Instead, we have developed a new solution. ACE has responded by investing time and money into developing a NON-HF unique process for etching titanium and its alloys. We can successfully etch and profile metal for customers involved in producing intricate medical devices, which may have complex mesh patterns or require micro-etched channels.