What is 3D Metal Printing?

3D metal printing (also called metal additive manufacturing) is a manufacturing process that creates metal parts by building them layer by layer from a digital 3D model, rather than cutting material away from a solid block or casting it in a mold.

Common metal 3D printing technologies 

• Direct Metal Laser Sintering (DMLS)
  
  • A thin layer of fine metal powder is spread over a build plate.
  • A high-powered laser welds the powder to itself.
  • This process repeats layer by layer.
  • Produces highly detailed, high density, strong parts
• Other kinds of 3D metal printing include
  • Powder Bed Fusion (PBF) [Note that SLS and DMLS are types of PBF], Directed Energy Deposition (DED), Binder Jetting, Metal Filament Extrusion, and more. 
  • VinjeFab specializes in DMLS printing and this article will not cover other kinds of metal 3D printing.

Pros

• Complex geometries
  • Can produce intricate internal channels, lattice structures, and shapes that are impossible or very expensive to machine.
• Minimal material waste
  • Unused powder is often recycled, making it more material-efficient than subtractive machining.
• No tooling required
  • Ideal for prototypes, custom parts, and low-volume production because there's no need for molds or dies.
• High-performance materials
  • Supports metals such as:
    • 316L stainless steel
    • Titanium
    • Inconel
    • Aluminum
• Good mechanical properties
  • Properly processed parts can achieve mechanical properties close to or comparable with wrought materials, depending on the alloy and heat treatment.

Cons

• High equipment cost
  • Industrial metal printers can cost hundreds of thousands to over a million dollars.
• Expensive materials
  • Metal powders are significantly more expensive than bar stock or filament.
• Slow production
  • Building parts layer by layer can take many hours or even days.
• Post-processing required
  • Parts typically need:
    • Support removal (for many geometries)
    • Machining of critical dimensions
• Surface finish
  • Printed surfaces are relatively rough compared to machined surfaces and often require finishing.
• Size limitations
  • Maximum part size is constrained by the printer's build volume.

Image by Formlabs