Laser process monitoring WeldWatcher®
Detect weld defects in the process and reduce repairs
The safety and quality requirements for many products are constantly increasing and their production is becoming more and more complex. With the monitoring of laser processes, possible defects can already be detected during welding, which significantly reduces subsequent time-consuming and expensive inspections. In order to make laser welding even more economical and process-safe, ABICOR BINZEL, in cooperation with 4D Photonics GmbH from Isernhagen, who have been developing and selling solutions for monitoring laser processes for 25 years, offers the laser process monitoring WeldWatcher® – a tool for monitoring and evaluating laser processes that can be easily integrated into the production process, such as in the automotive industry.
All information at a glance
- Process monitoring – optimising quality assurance by controlling process stability
- Application areas for laser process monitoring
- How does laser process monitoring work?
- Integration of the WeldWatcher® process monitoring into existing plants
- Process monitoring WeldWatcher®: the advantages
- Solution package ABICOR BINZEL & 4D Photonics
- Documentation
Process monitoring – optimising quality assurance by controlling process stability
Laser process monitoring is a major challenge for series production because the range of permissible parameter deviations is very limited, especially in the manufacture of precision components. Different factors such as machines, workpieces and ambient conditions influence the laser process. The smallest parameter changes can already mean that the welding of the component is no longer within the permissible tolerance. Process monitoring during the welding process is therefore an important part of quality assurance.
Process monitoring itself is not a quality measurement method, but rather an indicator of laser process stability. If the process stability is high, a high level of series quality is also achieved. Process monitoring can be seen as a tool that helps to detect the causes of defects at an early stage.
Predictive process monitoring
Particularly in automotive manufacturing, and primarily in the production of batteries and electric motors, it is advantageous to be able to detect faults during production. A subsequent repair of these high-quality components is difficult or even impossible from a technical point of view. Every defectively welded component is a reject and reduces the economic efficiency of the production plant. If defects are detected directly during welding, timely intervention prevents the system from producing further defective components – in this way, anticipatory process monitoring is achieved.
Laser process monitoring such as WeldWatcher® detects weld defects as they occur. Defective bridges or hairpin connections can be immediately rewelded or replaced. This prevents the need to remove complete components at the end of a production line. Another advantage of the laser process monitoring WeldWatcher® is that the statistical evaluations of all welding positions from previous production cycles help to maintain optimal process parameters.
Application areas for laser process monitoring in laser welding
- Welding of hairpins
- Welding of material pairs/material combinations such as copper on aluminum, copper alloy on stainless steel, etc., where intermetallic phases can form that are undesirably brittle
- Laser bonding – a joining technique for joining copper or aluminum bands for contacting in battery technology and power electronics
How does laser process monitoring work?
With each individual laser application, a characteristic process radiation is produced by the interaction of the laser light with the material. The change in this optical radiation indicates the course of the process. Via defined warning thresholds, which are adapted to the individual application, deviations and errors in the process are automatically transmitted to the system control. Defective parts are sorted out and reworked if possible. The data of the welded components are stored and can be used for traceability, if required.
Integration of the WeldWatcher® process monitoring into existing plants
A wide range of adapter modules allows the integration of the sensor technology into the laser itself or – if this is not technically possible – into the processing head for all common manufacturers. The WeldWatcher® process monitoring can just as easily be integrated into the beam switch, where the laser beam is deflected.
If the sensor can be integrated into the laser, this has the following primary advantages:
- In time-sharing laser processes – when a laser with the same power is operated serially via several optics – all beam exits can be monitored with only one WeldWatcher®.
- The mobility of the laser optics is not restricted by cables or sensors.
The process monitoring communicates with the system control, whereby an automatic component allocation takes place. In the event of a defectively welded component or weld seam, this can be easily traced back through the recorded data.
Solution package ABICOR BINZEL & 4D Photonics
With more than 1600 systems installed internationally, 4D Photonics has extensive experience in laser process monitoring. Depending on the application, the laser process monitoring experts create a concept, configure the system and take care of commissioning and training. Together with the worldwide sales and service network of ABICOR BINZEL, you can thus make your laser welding processes even safer and more economical.