How Metal 3D Printing Works
Let’s say you need a metal part. Your design is complete and now its time to manufacture. Which way makes sense? Do you want to start from a bulk of metal and machine away until you reveal the part (subtractive manufacturing) or do you want to build it layer-by-layer (additive manufacturing).
Computers have changed everything. Manual operations can now be automated and scaled up by orders of magnitude – what you could do in the 10’s before, you now do in the millions. Welding can be viewed in the same way. With modern automation, we can now make millions of computer controlled welds quickly and cost effectively.
What if we took this to its ultimate conclusion. What if we tried to create an entire part from welding? That question is at the core of laser powder bed fusion (L-PBF).
In Additive Manufacturing or 3d Printing, we print parts, layer-by-layer, just like you might print a book, page by page. Imagine examining a part in CAD and manipulating the Z-axis upward – this creates a good visual for the overview of the process.
L-PBF is essentially a welding processes that uses computer guided lasers to melt powdered metal, layer-by-layer, to create a part. The result is a fully dense part that exceeds the mechanical properties of a traditional casting process as-printed and, because it is fully automated and monitored with modern metrology, is more traceable too.
To begin, print preparation software analyses the design and ‘slices’ it into 50 micron thin layers creating instructions for the laser(s). Similar to the speeds and feeds of a CNC machine, the printer runs on instructions or ‘recipes’ for the laser power, spot size, and pattern strategy.
With VELO3D’s solution, each feature of the part is automatically analyzed for the best recipe assignment with different assignments given for contour, bulk, and angles. The software allows engineers to orient and support the part if needed to ensure a successful print. The engineer may also choose to simulate the print prior to sending the instructions to the printer to check for any potential issues.
Just before printing, an operator runs various calibration routines to ensure that the printer is in a ready state. Once the printer receives its instructions, the build begins. For each layer a ‘re-coater’ creates a new coat of planar powder on top of the powder bed. Computer-guided lasers apply pre-determined recipes or patterns on the powder bed to weld each new layer of metal onto the previous layers. This process repeats to create a fully dense, metal part.
At the end of the print, the part is covered in residual metal powder. The excess powder is vacuumed away and recycled revealing the printed part. Depending on the application, the part might need to be post processed which could include cutting, heat treatment, or machining.
Each part might be made from thousands of layers, composed of millions of laser patterns – billions of events to create a single part! Advanced metrology aided by constant computer tracking of build events and chamber conditions ensures that each part meets specifications. For larger parts, this may result in up to a terabyte worth of data which the VELO3D AM printer simplifies into an easy to read ten-page summary for optimal quality control.
The merging of well-established welding practices with modern lasers and computers is pushing the limits of manufacturing. We are now able to weld parts entirely from metal powder in a measured, automated, manner resulting in new geometries printed with a high degree of traceability.
Whether you need on-demand manufacturing of existing designs or improved geometric freedom for your next innovation, if your part is made from Titanium, Inconel, or Aluminum (or comparable material) and you can fit it through a basketball hoop, our engineers can help you today.
VELO3D, an award-winning metal Additive Manufacturing (AM) solution provider, helps high-performance companies in the aviation, oil and gas, and power generation industries unlock the benefits of AM. With the industry’s only SupportFree L-PBF capability and a semiconductor inspired quality control, we enable on-demand manufacturing of production quality parts with an unprecedented degree of design freedom.
The VELO3D full stack solution includes: Sapphire® metal AM production printer, Flow™ print preparation software, Assure™ quality assurance and control system, and an integrated manufacturing process that runs throughout the printing operation. Our solution enables greater geometric freedom to print SupportFree zero-degree overhangs, high aspect ratio walls, wide inner diameter enclosures, and FreeFloating metal parts with no connection to the build plate all at production quality levels.