Learn the Process of Achieving Dark and Secure Engravings on Medical-Grade Stainless Steel Tools

Deep Black Marking with PICO Lasers

When it comes to engraving black markings on stainless steel instruments and implants in the medical technology industry, manufacturers must carefully consider various factors. This includes meeting the unique requirements of medical technology, understanding the properties of the materials being used, and ensuring the overall efficiency of the marking process. By utilizing advanced laser technology, a vision-based marking system, and comprehensive software, these challenges can be effectively addressed.

The Challenges of Medical Part Marking

Direct part marking is required for reusable medical devices and ensures that traceability standards are met per FDA and MDR UDI directives (Unique Device Identification). The marking of stainless-steel instruments is especially challenging due to their material properties and product life cycles.

Traceability and product safety can only be guaranteed if the marking is permanent and legible: It is crucial that the marking is sharp in contrast, non-reflective and first and foremost withstands the passivation process. The mark must survive numerous cleaning and sterilization cycles so that it neither fades nor corrodes. Therefore, a marking solution is required that is particularly gentle on the material and at the same time powerful.

It must be taken into account that stainless steel exists in many different alloys. Depending on the compound, the material properties change and thus react differently to external influences, such as laser marking. The high demands on marking quality mentioned above can only be fully met if the proper type of laser is chosen at the beginning i.e. wavelength as well as utilizing a true Pico laser which outpaces a Femto laser in speed and creates light trapping cones to render the refractive index to a deep black that will withstand citric passivation when treated per ASTM A967/A967M – 17. Also the surface finish (from matt brushed to high gloss polished) has to be considered.

But not only material-specific challenges must be solved by a laser system that is suitable for marking medical stainless steel. A user-friendly, safe marking process is also essential for medical device manufacturers. Likewise, the marking system should be easy to integrate, enable smooth connection and support future-oriented automation solutions.

The Answer – A Comprehensive Blend of Technology and Processes

When it comes to marking medical products made of stainless steel, PICO laser like the Cobalt RX has distinct advantages. These lasers use extremely short pulse durations in the picosecond range, resulting in minimal heat affecting the material during marking. As a result, the markings are gentle and precise, with a matte and Deep-black appearance that remains consistent regardless of lighting angles. Not only does this technology provide clear and long-lasting markings, but it also ensures resistance to external factors. The key to achieving this is the ability to adjust the marking parameters to suit the specific material being used. The Cobalt RX excels in this aspect by offering flexibility through a wide range of pulse widths, allowing for precise customization for optimal results and material-friendly markings.

Another notable feature of the LMT system is the unified control software, 64-bit lasermark 3, which manages all aspects of machine control. This all-in-one solution streamlines setup and operation, making it fast, straightforward, and user-friendly. Compatibility with various interfaces allows for seamless connectivity with automation solutions.

The compact design of the PICO laser makes it versatile for any production environment. When integrated into a LMT Cobalt RX-Series machine, the laser can be operated using the Medical User Interface, which includes all necessary steps for UDI validation and job setup.


The Cobalt RX effortlessly solves the difficulties of engraving medical-grade stainless steel with its flexibility and efficiency. Its built-in automation offers significant benefits for ensuring product safety and enhancing productivity while also being cost-effective. Our expert laser professionals provide personalized consultation and determine the best marking parameters, along with assistance in machine validation, making LMT’s comprehensive package truly innovative.