3D Laser Systems for Precision and Flexibility Te evolution of 3D laser machines used widely in the
aerospace and automotive industries has led to platform- based machine designs that provide the volumetric precision required for 3D cutting, drilling, and welding of medical de- vices. In addition to providing capability for higher processing speed, fiber laser systems provide improved process control, repeatability and versatility.
designs and to develop processes for new designs that could not be realized reliably or cost effectively using Nd:YAG laser processing. Here’s how: Miniaturization: One of the most important trends
in medical device design is miniaturization. In a growing number of applications, physical size is an enabling attribute. Device size is linked to the size of various parts of the body and small size is almost always preferred.
Fiber laser enables device miniaturization through its smaller focused beam size.
Today’s 3D fiber-laser systems include controls that are
faster (higher bandwidth), are more intelligent and able to support the faster processing rates and more intricate patterns. Te robust structure of these systems ensures component rigidity to maintain precision throughout complex contours as the individual machine axes accelerate/decelerate throughout a higher speed range. A greater array of choices for the configuration of the
systems is available based on the size of the workpieces. Tese include a combination of workpiece motion and laser beam motion features. As an example, the Laserdyne 430 is equipped with a BeamDirector two-axis (rotary and tilt) laser beam posi- tioning head capable of cutting, drilling, and welding. Today’s laser systems are controlled so that laser param-
eters can be changed throughout the process (within limits of the laser source). Te way laser power is controlled at the beginning and end of each weld is important if high-quality, defect-free welds are to be consistently achieved. To this end, accurate power ramping at the weld start and weld end points is an essential feature of any laser welding system. Process control and verification are key requirements
for medical device manufacturing. SPC (Statistical Process Control) Data Acquisition, using both Nd:YAG and fiber lasers allows the user to monitor and record, as a part pro- gram is executing, key processing data used to create each part. In the part program are codes that specify data for collection by the SPC Data Acquisition feature. Te system monitors key parameters (i.e., time, date, temperature, posi- tion, commanded and/or actual laser power, pulse condi- tions, etc.) and stores the data to permanent storage as a text file. Data from the text file can be easily archived and used for further analysis.
Implications What does this mean for medical device manufacturers
and subcontractors? While the fiber laser provides manufac- turers the ability to duplicate existing processes that have been developed for a system having an Nd:YAG laser, it also pro- vides the capability to increase productivity for these existing
As previously noted, the quality (divergence) of the beam
from a given laser impacts the ability to focus the laser. Tis in turn influences the size of parts that can be laser processed, the size of features that can be cut, the size and shape of holes that can be drilled (laser produced holes need not be only round), and size of parts that can be laser welded. Fiber laser enables miniaturization through its smaller focused beam size. Troughput: With higher average power for fiber laser, the
pulses used to produce a smooth cut, drill an array of holes, or produce a seam weld by a series of overlapping pulses can be delivered at higher rates allowing higher throughput. For example, cutting and trepan drilling (producing a hole by cutting the circumference) a 3-mm-thick, high-temperature stainless steel using a fiber laser is more than 3× faster than for a Nd:YAG laser. Tis higher processing speed not only provides lower cost
in manufacturing existing designs, it makes possible use of fiber laser where Nd:YAG laser was previously uneconomical. Versatility: Compared to other industries, the medical
device sector has been slow to outsource manufacturing components, due in part to concerns over product quality. Te latest laser systems address these objections to outsourc- ing by providing controls for consistency of manufacturing processes. Fiber lasers eliminate the need for power and beam quality changes over time due to aging flashlamps. Also, fiber lasers eliminate the need to change optics within the laser head when switching between cutting and welding (skill dependent). 3D fiber-laser systems also provide flexibility for laser cut-
ting, drilling, and welding of both two- and three-dimensional components. Tese systems are designed with standard features (e.g. database of laser parameters for commonly processed materials) making development and setup of new processes straightforward. Multiaxis laser processing with fiber lasers not only
provides new capability and versatility important to medical device manufacturers, it also means that older, less reliable equipment now can be replaced with maintenance-free laser systems that do more and higher-quality work.