What is Multi Jet Fusion?
Multi Jet Fusion is an additive manufacturing technology developed by HP and unveiled in May 2016, causing industry-wide excitement and apprehension in equal measures. MJF sits within the Powder Bed Fusion (PBF) family of technologies and shares aspects of both SLS and Material Jetting processes.HP claims that MJF is up to 10 times faster than competing technologies, able to print up to 12000 voxels per linear inch per layer (voxels are to 3D as pixels are to 2D).
In order for 3D printing to go from a prototyping tool to an industrial manufacturing one, machines need to be able to do two things: produce accurate, high-quality/resolution parts with optimized mechanical and functional properties; and do so consistently. It is precisely here that MJF offers certain advantages.
How does Multi Jet Fusion work?
MJF uses two perpendicular carriages that work concurrently to process parts — one applies a fresh layer of material across the work area, whilst the other prints functional agents. In a continuous pass, the carriage that prints the functional agents also provides the energy source needed to sinter the material. A closed loop thermal control system measures the temperature of the material bed and instructs the energy source which areas require more or less energy to give control over layer-to-layer fusing. This level of control is what allows MJF printed parts to be mechanically optimized, accurate and repeatable.
Unlike Binder Jetting which jets a single binder onto the material, MJF jets two functional agents on a voxel-level: one is a fusing agent which denotes where the material will be sintered, and the other is a detailing agent which is applied to the edges of the part in order to inhibit sintering. This combination allows the system to ensure that parts are properly fused; with edges that are smooth and well-defined.
As with all ceramics AM technologies, MJF produces green parts that need sintering to achieve final part density.
Available MJF 3D printers:
There are are two MJF 3D printers available — the Jet Fusion 3D 4200 and the Jet Fusion 3D 3200, plus the new and improved Jet Fusion 4210 recently introduced. The main differences between the 4200 and the 3200 models are the building speed — 4500 cm³/hr and 3500 cm³/hr respectively — and the layer thickness — 0.07 to 0.12 mm and 0.08 to 0.10 mm respectively. Both machines have an effective building volume of 406 x 305 x 406 mm.
Both also come with the HP Jet Fusion 3D Build Unit which allows for a continuous printing process by being able to be moved from the printer directly to the post-processing station for cooling and cleaning as soon as printing has finished. Part of the HP Jet Fusion 3D Printing Solution is the HP Jet Fusion 3D Processing Station which comes with or without the Fast Cooling Module.
|Model||Jet Fusion 3D 3200, 4200, 4210|
|Technology||Multi Jet Fusion|
|Materials||Plastic, Ceramics, (metal possibly coming in 2018)|
|Effective Build Volume||406 x 305x 406 mm|
|Layer Thickness||0.07 to 0.12 mm|
You can find the specifications for each machine and the Processing Station here.
Further reading on HP and MJF:
• HP’s Fabio Annunziata Discusses Key Strategies for MultiJet Fusion 3D Printing Materials
• HP Announces Faster 3D 4210 System for Production and 3 New Materials (Including PP)
• What’s Next for Stratasys and 3D Systems After HP’s Announcements