Additive Manufacturing

Additive Manufacturing Processes

What is additive manufacturing?

GE Additive specializes in developing Powder Bed Fusion (PBF) machines for the additive manufacturing of metal parts. The two processes GE offers with in the PBF category, recognized by the American Society for Testing and Materials (ASTM), include:

 - Direct Metal Laser Melting (DMLM)
 - Electron Beam Melting (EBM)

The PBF process creates a physical object from a digital design or CAD file. In all of GE Additive’s machines the process involve the spreading of the metal powder layer by layer and uses either a laser or electron beam to melt and fuse powder together to create a part. The process repeats until the entire part is created. Loose or unfused powder is removed during post processing and is recycled for the next build.

Direct Metal Laser Melting (DMLM) Process

The direct metal laser melting (DMLM) process involves the full melting of metal powder into liquid pools. As with other PBF processes, an .STL file is generated from computer-aided design (CAD) data, which guides the “printing” of sequential, micro-thin layers of fully melted metal powders. Various metals can be used, including titanium, cobalt-chrome and aluminum alloys. When printing is complete, excess powder is removed, leaving a high-resolution object with a smooth surface that usually  requires little or no post-processing.

In aerospace, DMLM has been used to fabricate parts for jet engines and other airplane  parts. For example, Fortune highlighted how GE is printing fuel nozzles for its CFM LEAP engines using this technology. Thanks additive’s ability to produce complex geometric structures, the design of the 3D-printed fuel nozzle reduces 20 traditionally fabricated parts down to just one.

Applications

DMLM is a particularly useful process for time-constrained projects and prototyping. Its ability to fabricate complex structures reduces assembly times and often increases structural integrity by reducing the number of components required. 

Electron Beam Melting (EBM) Process

Electron beam melting (EBM) process involves metal powder melted by of a beam  of electrons gathered and focused by electromagnetic coils. Given the inherent nature of the 3,000-watt electron gun, the process must be carried out in a vacuum chamber. EBM is used to print sophisticated parts and components of many kinds, including those that supply the aerospace and medical industries.

In the medical industry, EBM technology is used to fabricate one-of-a-kind orthopedic implants. The EBM process yields objects with slightly rough surfaces, so some machining is appropriate when smooth surfaces are required. However, the rough surface is actually an advantage when fabricating implants because it promotes bone-in growth.

High-quality mechanical properties are achieved, in part due to temperature consistency that strengthens fused layers. EBM machines use titanium alloys to produce parts for high-temperature, high-stress aerospace applications.

Applications

EBM can be a time and cost-effective way of producing high-density bespoke projects. The unique stacking ability EBM machines maximizes the capacity of the build chamber and enables efficient production of orthopedic parts.

Transformative technology—Electron Beam Melting (EBM)

The EBM process utilizes a high-power electron beam that generates the energy needed for high melting capacity and high productivity. The hot process allows you to produce parts with no residual stress and the vacuum ensures a clean and controlled environment. 

Click here to see an illustration of how the process works

 


Binder Jetting Process

GE Additive is developing a Binder Jet machine. This process involves a print head that moves across a bed of powder and selectively deposits a liquid binding agent in the shape of the section, bonding these areas together to form a solid part one layer at a time. 

When the build is complete, the bound parts are removed from the unbound powder. Materials commonly used in binder jetting are metals, ceramics, and sand. For metal printing, a debind and sintering process is required to remove the binder and fuse the metal powder into a solid metal part.

 

Applications

Binder jetting is ideal for mass production applications. This technology is unlocking the power of additive design for volume production in automotive, industrial, medical and aerospace applications, among others.

News

Visit our News section to learn how GE Additive’s EBM and DMLM machines are allowing progressive enterprises to take advantage of the many benefits of additive manufacturing.

Machines

Featuring some of the most advanced additive technologies available, machines from Arcam EBM and Concept Laser enable customers to grow products quickly and precisely.