Abstract
The European Union regulates that a Unique Device Identifier be directly marked onto all reusable medical devices, Class 1 devices by May 2027, MDR Article 123(3)(g), Article 27(4). Stainless steel is common for medical device design. This study investigates viable methods of laser marking the UDI onto steel that will not harbor pathogens or reduce device lifespan. The UDI is in the data matrix format. Four marking parameters, line spacing, laser power, pulse frequency, and scan speed were independently tested to determine the ideal values. These were evaluated by using a novel Test Mark where a gradient of laser power is applied. This mark produces bands characteristic to the sample and marking parameters. Length measurements of these bands allow for sensitive performance evaluation of mark parameters. The reaction of the Test Mark to passivation and corrosion testing allow selection of parameter values which best endure the testing. This Test Mark allows extraction of quantitative and continuous data which offers an advancement over the qualitative and discrete data the traditional Hatch Grid method for laser parameter assessment provides.