4 months ago

Important Considerations for laser marking an identifier on die-casting

This white paper covers the impact of contrast, Data Matrix Size and optical power of the laser on the time required to mark a DMC. It also discusses laser safety for open-air enclosures and for a closed laser safety enclosure with rotary table. But why stop at that. We also discuss the impact of post treatment process on the legibility of DMC and strategies to make the DMC legible even after shot blasting. Have a look, you'll be glad you did. Feel free to contact us at: Browse our website at: Get in touch on our social media channel: Facebook: LinkedIn: Twitter: Google+: YouTube: Xing: Instagram: Viadeo: Learn more on our laser marking & traceability, laser cleaning and safety standards blog Blog:


CAMERA READING AND CONFIRMATION To ensure fully “bulletproof traceability”, a camera reading of the code ong>anong>d a comparison with the data to be marked may be very useful. If the part is successfully read ong>anong>d compared positively to the requested mark the traceability on that part cong>anong> be 100% certified. Also, as code ong>markingong> often includes strict rules on quality, the camera reading step will ensure that the marked codes respect the quality criteria specified by the mong>anong>ufacturer or the customer. Laser mark ong>identifierong>s on aluminum have excellent grading values when they are not altered by ong>anong>y post process. However, most post processes, ong>anong>d particularly shot blast, will have the effect of decreasing the grading of the mark (decrease in quality after the process). Nevertheless, ong>forong> the shot blast parameters that we tried with Mercury Marine, with the appropriately chosen set of ong>laserong> parameters, it is possible to read the code after shot blast, as we explain in detail in the following sections. LASER SAFETY The 1.06 µm fiber ong>laserong> wavelength is within the 0.4 µm – 1.4 µm wavelength rong>anong>ge considered the “dong>anong>ger zone” ong>forong> the humong>anong> retina. To ensure the affected personnel is appropriately protected, it is strongly recommended to integrate the ong>laserong> ong>markingong> system inside a Class 1 ong>laserong> machine. The ANSI 1040.10 is the stong>anong>dard that applies in the United States while the IEC 60825-1 is the one ong>forong> Cong>anong>ada ong>anong>d Europe. In addition, in the US, the integrator must register the final ong>laserong> machine with the FDA through the CDRH (Center ong>forong> Devices ong>anong>d Radiological Health). Although there are multiple ways to integrate a ong>laserong> in ong>anong> industrial environment, the two methods described in this section are well suited ong>forong> die casting: The open air enclosure with limited access, ong>anong>d the sealed enclosure with turntable. Figure 5- Open air enclosure. The ‘open-air’ safety enclosure is shown in Figure 5 above. The enclosure is actually made of three separate enclosures: An outer one [Fig.5 (1)], ong>anong> inner one [Fig.5 (2)] ong>anong>d a humong>anong> access barrier [Fig.5 (7)]. These three barriers/enclosures used together are necessary to assure ong>laserong> safety ong>anong>d respect the ANSI 1040.1 stong>anong>dard. The inner enclosure’s purpose is to decrease the ong>anong>gle rong>anong>ge through which the beam could potentially be reflected after ong>anong> unong>anong>ticipated reflection. Considering the part geometry ong>anong>d the gap between the part ong>anong>d the inner enclosure (which is ensured by the use of two proximity sensors), the possible paths of dong>anong>gerous rays are shown in red in Figure 6.

Figure 6- Possible specular reflections (in red). The purpose of the outer enclosure is to block these rays from coming out as specular rays, which are dong>anong>gerous over several tens of meters/yards. This enclosure must be made of absorptive ong>anong>d diffusive material such as black ong>anong>odized aluminum or black painted steel. The reflection of the incoming ong>laserong> light inside this enclosure will be scattered in all directions, greatly reducing the dong>anong>ger zone emerging from the inner enclosure. This dong>anong>ger zone is shown in orong>anong>ge in Figure 7. It cong>anong> have a maximum radius of 80 cm ong>forong> the LXQ-100 (100W) ong>anong>d 36 cm ong>forong> the LXQ-20 (20W). Figure 7- Possible diffuse reflections (in orong>anong>ge) The third part of the enclosure, the humong>anong> access barrier, ensures that no humong>anong> cong>anong> get access to the remaining dong>anong>ger zone when the machine is in operation. Although procedural safety meong>anong>s are already installed to limit access to the cell while it is in operation, these procedures are not acceptable under the ANSI 1040.10 stong>anong>dard that requires engineering meong>anong>s to prevent humong>anong> access to radiation above the intensity limit of the stong>anong>dard, which is 5 mW/cm 2 ong>forong> the 1064 nm wavelength ong>anong>d the 100 ns pulse duration of the LXQ ong>laserong> series. These engineering meong>anong>s cong>anong> be a physical barrier as proposed, but could also be a zone scong>anong>ning tool or a sensing mat. If a physical barrier is possible, it is preferred. Otherwise ong>anong>other engineering meong>anong>s should be employed.

Laserax Industrial Laser Solution for the Automotive industry
Laser cleaning solution
Traceability and Laser Marking of Die Castings
Laser Marking and 3D Imaging of Aluminum Products
Laserax Modular Approach to Laser Marking and Cleaning Systems
Laserax - Mobile Laser Cleaning System
Surface Aanlysis Study of Laser Marking of Aluminum
Technical Specification - Laserax LXQ 3D
Technical Specification - Laserax LXQ
Technical Specification - Laserax LXQ 3D Vision
Review of technologies for identification of die casting parts