“All I ask for is one simple request, and that is to have sharks with frickin’ laser beams attached to their heads!” (Credit: Dr. Evil, Austin Powers Goldmember). Perhaps, if Dr. Evil was an Additive Engineer, he may have rephrased as such: “All I ask for is one simple request, and that is to have Additive Machines with frickin’ femtosecond lasers attached to their optic systems!” Pretty cheesy, but you get the gist.
Femtosecond lasers have been used for decades in micro-machining to achieve machining with nearly zero thermal stresses and precise dimensional tolerance. Due to the short pulse width and high energy of a femtosecond laser, thermal stresses are kept local and do not deform surrounding areas of the metal.
PolarOnyx, an additive manufacturing company based out of San Jose, California, has created a first-of-its-kind femtosecond laser-based additive system. Traditional DMLM (Direct Metal Laser Melting) machines use what’s known as CW or Continuous Wave lasers. These lasers, although ideal for low-temperature parts such as aluminum and titanium, have shown to have challenges with higher-temperature materials such as tungsten and iron. Higher-temperature materials require quite a bit more energy to bond metal particles together as compared to their lower temperature counterparts. Due to this increase in energy, CW lasers must output much more laser power. However, their pulse duration (i.e. how long the laser stays on) does not change. Thus, surrounding metal particles are affected and what are known as “thermal stresses” are built into the part itself.In comparison, femtosecond lasers with their much shorter pulse duration are able to instantaneously ionize and bond the metal particles together with nearly zero thermal stresses. By being able to instantaneously melt particles together, femtosecond lasers also have an innate advantage in building denser parts.
Additionally, PolarOnyx was also able to successfully print iron powder directly on glass. Iron and glass have different but very close melting temperatures. With traditional CW lasers, the thermal buildup would have caused the glass to crack. However, with the femtosecond laser process and its ability to quickly fuse the iron powder, the iron was able to melt without causing any damage to the glass substrate.
Most interesting is PolarOnyx’s vision for a process whereby both the additive and subtractive properties of femtosecond lasers are integrated into one machine. Although metal additive has come a long way, there are still cases where complex features must be machined post-print. With femtosecond lasers, this task could be done all in one process with one machine. The femtosecond lasers could first additively build a layer, followed by a subtractive ablation of the same layer where tight machining dimensional tolerances are required.
If only Dr. Evil would have known about femtolasers, he may have been more specific in his request!
You May Also Like
Making Custom Models for 3D Printing with Daz Studio
Blender is a great solution for professional-quality models, and with practice, you can achieve satisfactory results. However, if you find yourself throwing your hands up in exasperation during the process,...
The KAV 3D Printed Bike Helmet on Kickstarter
One area where we’ve seen a lot of 3D printing activity is in helmets. Now, KAV is joining the fray with a mass-customized, made-to-measure helmet. The company says that machine...
Satori Launches Kickstarter Campaign for New Large-Volume VL2800 3D Printer
After a long wait, it’s finally here: the Kickstarter campaign for the new large-volume, industrial-grade Satori 3D printer, the VL2800, officially launched this week, and in less than ten hours...
3D Printing Webinar and Event Roundup: May 16, 2021
Even as we get closer to the official start of summer, that doesn’t mean the amount of webinars, virtual events, and live events are going down; in fact, the opposite...
View our broad assortment of in house and third party products.