2 September 2010

Ultra-Short-Pulse Laser for Cutting Semifinished Nitinol

The ultra-short-pulse laser reduces the postprocessing of implants to basic cleaning by means of ultrasound.

Buyer’s Guide 2010 Update: Manufacturing Equipment

An ultra-short-pulse laser from Rofin-Sinar is offered to minimize the need for postprocessing of medical implants laser-machined from tubular semifinished nitinol stock. The laser not only saves processing costs; it also reduces the percentage of rejected parts, a common problem with the sensitive shape-memory alloy.

Cutting by means of laser light emitted in microsecond pulses has been standard practice in manufacturing implants made from tubular stock. But even with optimally configured laser machines, this cutting method leaves behind burrs, especially in hard-to-access tube interiors. These burrs have to be removed manually before a chemical cauterizing procedure is applied to remove oxide layers and the intersections are rounded off via electrochemical polishing.

If postprocessed chemically or mechanically, the nitinol can be damaged. An extremely high reject rate can result. Using the Rofin laser, however, reduces postprocessing requirements to basic cleaning by techniques based on ultrasound.

In addition, bioresorbable stents made of plastic have been the focus of numerous R&D efforts. The bioresorbable plastics being studied for this use, such as polyactides and polyglycolides, cannot be processed with conventional cutting lasers owing to their low melting points and poor absorption. Heat transfer to the material has been too great. However, the ultra-short-pulse laser had been able to cut stents with perfect edges and precision from these plastics.

For further information:

Rofin Baasel Lasertech
Starnberg, Germany
www.rofin.com