Multi Jet Fusion (MJF) 3D Printing Technology Overview

HP Multi Jet Fusion (MJF) is one of the most commonly used 3D printing technologies for producing durable parts with high accuracy. Compared to its powder bed fusion counterparts like selective laser sintering (SLS), MJF prints are more cost-efficient at scale. The technology excels at creating complex geometries with fine details, making it ideal for both prototypes and end-use applications.

How MJF Works?

MJF technology follows a precise multi-step process to produce highly accurate and durable 3D-printed parts. Here’s how MJF works:

1. Powder Layering – A thin layer of polymer powder is spread evenly across the build platform.
2. Agent Deposition – An inkjet head selectively deposits two liquid agents: a fusing agent, which marks areas to be melted together, and a detailing agent, which defines fine features and prevents unwanted fusing.
3. Thermal Fusion – A heating unit moves across the powder bed, fusing the areas where the fusing agent was applied while the rest remains as loose powder. This ensures isotropic mechanical properties in the final part.
4. Layer Recoating – After each layer is fused, the build platform lowers by 80 microns, and a fresh layer of powder is spread, repeating the process until the part is complete.
5. Cooling & Powder Removal – Once printing is finished, the build cools before parts are extracted. The surrounding loose powder, which acts as a natural support, is removed and can be reused, minimizing material waste.

After printing, parts may undergo post-processing such as bead blasting, dyeing, or vapor smoothing to enhance surface quality and appearance.

Materials for Multi Jet Fusion 3D Printing

Plastic materials used for MJF 3D printing can be divided into two categories:

• Rigid plastics: Nylon PA11, Nylon PA12, PP
• Flexible plastics: Estane 3D TPU M95A

MJF PA 12 natural

PA 12 media tumbled white

MJF PA12 Flame Red

MJF PA12 Violet Blues

Advantages of Multi Jet Fusion 3D Printing

MJF is one of the most popular 3D printing technologies applied for prototyping, for small batch production and thanks to its efficient scalability also for mid-sized series production. It has a set of advantages that makes it a unique 3D printing technology.

MJF Eliminates the Need for Support Structures

Since MJF 3D printing belongs to the powder bed fusion additive manufacturing technology, its designs do not need any support structures. While printing, all the empty spaces are filled with the unused loose powder, making MJF prints self-supportive. Multi Jet Fusion can be the best solution for printing complex designs instead of printing in multiple parts which generally is an issue when the alternatives like FDM are used.

MJF Prints Parts Directly in Colour

Multi Jet Fusion is one of the few technologies which can print engineering-grade plastics  (Nylon 12) in full-colour. With this technology you can produce full-colour functional parts while maintaining optimal mechanical properties. Since it is indirect 3D printing, it is capable of creating full spectrum color parts with a voxel-control system and is much more accurate with colour reproduction.

MJF Has Good Physical and Mechanical Properties 

With MJF, printing a part in ultra-thin layers (80 microns) is possible. This results in low porosity and high density, which contribute to high resolution and good dimensional accuracy. The surface finish of MJF-printed parts is naturally very good. Additionally, the process ensures consistent isotropic mechanical properties, making Multi Jet Fusion ideal for functional prototypes and small batches of end-parts. The MJF 3D printing process produces highly isotropic parts with high strength and consistency in all directions.

Multi Jet Fusion Has a Good Price-Quality Ratio 

Even though FDM can be a cheaper option, the dimensional accuracy and mechanical properties from the MJF part is much superior for almost the same price as FDM. Colouring and surface finish costs are also reduced as the prints come out coloured with good surface finish directly from the printer without the fuss of additional post processing.

MJF Has a Short Lead Time

The MJF process is quick in terms of printing speeds, even faster than SLS. Since the powdered material is easily available and the technology itself is more suitable for larger volumes than its counterparts thanks to the possibility to print several parts at once, MJF is commonly used for printing mid-sized batches as well. 

MJF Produces Less Wastage

With MJF 3D printers, usually more than 50% of material is good enough to be reused after a print. It is aided by the processing station which sucks excess material back into the printer to be reused and can also clean prints. Less wastage also results in powder conservation and less environmental damage.

Disadvantages of Multi Jet Fusion 3D Printing

Apart from the advantages it offers, there are also a few common disadvantages that MJF possesses.

MJF Has Limited Material Options

MJF can only print with nylon powders (PA 11, PA 12), PP and TPU, whereas FDM has many more varieties to print with apart from the materials that MJF uses (like ABS, PETG, PLA, etc). Other printers can also support food grade materials. If the requirement matches the limited material availability of MJF, it’s a good option.

MJF Prints Have a Rougher Surface

Parts printed with MJF have good surface quality but it is rougher than the surface finish of parts produced by expensive options like stereolithography or Polyjet. Though parts can be post processed (media tumbling or vapour fusion) to improve their final surface quality, this additional finish increases the time and cost of the overall process.

Xometry’s MJF 3D printing Services

Xometry Europe offers Multi Jet Fusion services online, for on-demand 3D printing projects, for both prototypes and large batches. With a network of more than 2,000 partners all over Europe, Xometry is able to deliver MJF 3D printing parts in up to 3 days. Upload your CAD files to Xometry Instant Quoting Engine to get an instant quote with various manufacturing options available for MJF 3D printing.

eBook: HP Multi Jet Fusion Design Guide

Download our guide for HP MJF manufacturability recommendations to optimize your designs and lower your costs.

Download Guide

Bookmark (0)

Close

Paylaş