Things to Consider When Purchasing a Metal 3D Printer

3D printing has been around for over 30 years now. The first stereolithography machines were developed in the mid-1980’s. Around the same period, Selective Laser Sintering was introduced by Dr. Carl Deckard and Dr. Joe Beaman at the University of Texas at Austin. Their method has since been adapted to work with a range of materials, including plastics, metals, glass, ceramics, and various composite material powders. Today, these technologies are collectively categorized as powder bed fusion—additive manufacturing processes by which thermal energy selectively fuses regions of a powder bed.

When used with plastics, this process is referred to as SLS, whereas metal-based processes are known as direct metal laser sintering (DMLS) or selective laser melting (SLM).

Historically, these processes for metal 3D printing have been prohibitively expensive, and only accessible to very large manufacturing companies and large scale service bureaus.

This all changed 2017 when a new process was announced: Atomic Diffusion Additive Manufacturing. As opposed to a laser fusing metalic powder layer by layer on a build platform, in ADAM processes, the powder is encapsulated in a polymer matrix. The material is then extruded through a nozzle in a process that is very similar to traditional FDM (Fused Deposition Modeling). When the build is complete, the polymer matrix is dissolved away in a solvent bath, and the part is sintered in a furnace.

This new process offers metal 3D printing at a price point which is significantly lower than traditional DMLS and SLM processes. Also, the fact that the base material is bound in a plastic matrix means environmental concerns are reduced to negligible levels creating an office friendly machine.

Major players in this arena are now bringing their solutions to market. Before making that final financial commitment, one should consider several factors that will impact the quality of the final parts as well as the over-all cost of ownership.

Because of it’s similarity to FDM printing, one would expect multiple material options to be available on an ADAM style machine.  Be sure that the machine you’re evaluating has the available materials that you need.  Also inquire about new materials in development.  It’s also important to understand what’s involved in changing materials.  Is there a significant amount of waste when switching from one material to the next?  Also, are there any special tools required?  Finally be sure that one print head can run multiple materials, and that you don’t need to purchase a separate print head for each different option.  Finally, be sure that there are no additional “license” fees to add new materials to an existing machine.

Although one may believe that the printer itself is the most critical component of an ADAM system, it is really the sintering furnace or oven that has the most impact on over-all operation costs and part quality.

A term that most of us have never heard is a critical attribute of a high-performance sinter station:  Refractory Retort.   A Carbon-Free Refractory Retort is desirable to eliminate the introduction of carbon into the part, which would cause contamination and thus impact the mechanical properties of the final piece.

The run-time of the sinter process is also a key factor in over-all cost.  A shorter run time will not only produce more parts in a given period of time, but will also reduce operation costs such as electricity consumption.