What is MJF?
Multi Jet Fusion (MJF) is HP’s proprietary 3D printing process.
In MJF, parts are built by jetting a binding agent onto thin layers of polymer powder particles (typically nylon) and then sintering them using an IR heat source.
MJF produces functional plastic parts with isotropic mechanical properties that can be used for detailed prototyping or end-use low-volume production.
Our MJF 3D printing service
From prototyping to small-batch production, our global network of certified MJF 3D printing facilities will allow you to produce highly accurate parts with quality comparable to injection molding.
Upload your CAD file for a free quote and manufacturability review and get your parts into production in less than 5 minutes.
|Maximum build size *||380 x 285 x 380 mm (14.9'' x 11.2'' x 14.9'')|
|Standard lead time *||36 business days|
|Dimensional accuracy||± 0.3% with a lower limit on ± 0.3 mm (0.012'')|
|Layer thickness||80 μm|
* For expedited shipping or parts that exceed the maximum build size contact firstname.lastname@example.org.
Available materials for MJF 3D printing
MJF produces parts from engineering thermoplastics. Here is the list of our standard MJF 3D printing materials.
|HP PA 12 (Nylon 12)||Nylon 12 is a robust thermoplastic with all-around excellent physical properties and chemical resistance, ideal for functional prototypes and end-use applications.|
|Glass-filled HP PA 12||Glass-filled nylon is reinforced with glass bead and creates parts with higher stiffness and thermal stability than standard nylon.|
Available surface finishes for MJF 3D printing
Additional post processes can be applied to improve the appearance or mechanical properties of parts produced with MJF.
MJF parts with a wall thickness greater than 4 mm are watertight up to 20 bar without additional finishing.
|Gray||As printed MJF parts are typically gray in color and have a smooth surface, without visible layers, and a powder texture.|
|Dyed (black)||MJF parts are dyed black by immersion in a warm color bath. The color penetration reaches a depth of about 0.5 mm and covers all surfaces.|
|Spray painting *||MJF parts can be painted white, black or in a specified RAL or Pantone color.|
|Tumble smoothing *||The parts are placed in a tumbler that contains small ceramic chips, gradually eroding its surface down to a polished injection molding-like finish.|
* These finishes are available by contacting email@example.com.
Ideal MJF applications
Our in-house manufacturing experts recommend using MJF for the following use cases.
MJF is ideal for fabricating functional prototypes from durable, chemically resistant engineering thermoplastics.
Appearance: Smooth surface
Quantity: 1 - 5 parts
MJF is cost-competitive to injection molding for low-volume manufacturing of end-use plastics parts for quantities up to 300 units.
Appearance: Injection molding-like
Quantity: 10-300 units
Design guidelines for MJF
The table below summarizes the recommended and technically feasible values for the most common features encountered in 3D printed parts.
|Unsupported walls||1.0 mm (0.040'')|
|Supported walls||0.7 mm (0.030'')|
|Minimum detail size||0.25 mm (0.010'')|
|Minimum hole size||1.0 mm (0.040'')|
|Moving parts||0.5 mm (0.020'') between moving surfaces|
|Assembly clearance||0.4 mm (0.016'') between mating surfaces|
|Maximum wall thickness||20 mm (0.8''). Thicker parts must be hollowed and contain at least two escape holes for powder removal with a min. diameter of 8 mm (0.3'').|
Learn more about the process in our Knowledge Base article.