The laser ablation process produces patterns and textures that can be precisely reproduced from one part to the next, so much so they could be patented.

A new approach to laser ablation is showing strong potential for imparting specific surface patterns and textures onto metal parts and devices used in the medical industry. Typically, surface patterns are applied using expensive traditional metal cutting processes, multiple electrical discharge machining (EDM) operations, or hazardous chemical etching. Textures can now be generated cost effectively, quickly, and safely on a laser ablation machine.

Already used in a variety of applications ranging from surgical procedures to production of superconductors, the laser ablation process entails using a laser to sublimate material, or turn it directly from solid to gas. A laser ablation machine can be equipped with pulsed, fiber-optic lasers of varying strengths and a variety of lenses with different focal lengths to maximize productivity.

Laser ablation represents a process that is faster, quieter, and more repeatable, flexible, and environmentally friendly than conventional manual and chemical-based processes. 2D and 3D details are machined from a high-quality digital image, allowing completely reproducible results for specific textures, engravings, marks or labels imparted on a wide variety of materials, including graphite, aluminum, copper, steel, carbide, brass, and ceramics.

In the medical industry, surface texture has become an important, if not critical, aspect of product design. Consider, for example, surgical implants, often made of titanium and other metals that require special surface textures vital to the stimulation of bone or tissue growth onto or around the implant to secure it in place.

Medical shops usually cut implant patterns or textures using 5-axis machine tools. This is an acceptable option if the shop has excess 5-axis capacity or only a relatively small percentage of jobs that require texturing. Otherwise, opportunity costs quickly accumulate, as the equipment could be more productively used than for time-consuming texturing. Additionally, machining surface patterns and textures often requires small, specialized tools, which can further increase process costs.

Laser ablation produced textures and patterns are unaffected by varying part surface contours, as can be the case with chemical etching.

As for EDMing surface patterns or textures onto medical implants, the same holds true in regards to process time and better use of an expensive piece of equipment. Medical shops opting for EDM would have to machine the needed pattern or texture onto a graphite or copper electrode – most likely using an expensive high-speed 5-axis machine, then load that electrode into a sinker-type EDM, and “burn” the pattern into the implant.

Another potential medical application for laser ablation is in the manufacturing of metal tooling for molds used to produce components made from plastic or synthetic materials. These components could include artificial limbs or other plastic medical devices requiring specific surface textures or even graduated scales for measuring purposes, as with plastic syringes.

In the case of artificial limbs, a laser ablation machine, working from a scan of actual human skin, could impart that texture onto metal mold tooling, which would then reproduce the pattern when molding artificial limbs. The outside surface of these limbs would have the look and feel of real skin, and quite possibly a pattern scanned from the intended recipient’s own skin.

In addition to 5-axis machining and EDM, shops often chemical etch surface patterns or textures into the metal tooling used in molds. The process provides substantial time and cost savings, but isn’t as consistent and precise as the other methods.

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