MJF – a game changing additive manufacturing process
3D printing for production with MJF
Materials such as HP PA 12 Nylon and HP PA11 Nylon are starting to prove their worth in real world applications; and designers and engineers are starting to understand the specifics of designing for the additive manufacturing process. As a result, we are now seeing a sharp uptick in acceptance and application for 3D printing for production. In this article, we explore the benefits of 3D printing for production with HP’s Multi Jet Fusion, or MJF, technologies.
The obvious benefits additive manufacturing include production on demand, reduced weight, reduced wastage, reduced costs through the eradication of tooling, and reduced manufacturing time. But, the most significant contributor to this uptick is validity of the engineering-grade materials used. For HP’s Multi Jet Fusion (MJF), the ‘big brother’ to the ever-popular SLS, two stand out materials are available at Paragon Rapid Technologies.
HP PA 12 Nylon’s attributes include superb mechanical properties, durability, strength, excellent density, heat resistance, impact resistance and low porosity. Of course, the HP PA12 is also ideal for producing complex parts with thinner features thanks to the fact that there is no need for support structures.
HP PA Nylon 11 is HP’s contribution to sustainable plastics. Created from the castor oil plant, a wholly sustainable source of raw material, the PA 11 possesses almost all the attributes of PA12. It is ductile, has a slightly lower heat resistance but a greater impact strength, and is slightly more flexible after post processing.
In fact, when it comes to Net Zero considerations, polymer additive manufacturing with MJF certainly ticks the greater sustainability box. At the printing point, powder from both PA Nylons can be recycled. Both are also biocompatible and UV-resistant in accordance with ISO standards.
MJF prints fast. Without post processing in the form of shot peening and dyeing, parts can be ready for dispatch within two days – ideal for on-demand production scheduling.
Both PA 11 and PA 12 nylons are biocompatible, which means skin contact applications in the medical devices field, such as personalised prosthetics and orthotics are an obvious area for development. However, applications in this field can go much deeper, with components for electrical housing and moveable parts easily achieved in low numbers, without the need for expensive tooling and the inevitable wait times.
PA 12 Nylon is used extensively in the industrial products arena, particularly in the field of robotics and automation. Its robust, heat resistant properties that nevertheless allow for fine detailing make it ideal for end of arm tooling, electronics housing and switches. Equally it can be designed into electrical mounts and complex, rigid structures.
MJF additive manufacturing can be used to create mechanical and structural automotive and aerospace components where parts are complex and the resultant component needs to be light weight. Adding in a lattice to designs can help increase strength while reducing weight further. Applications include drone parts, automotive grills, engine mounts and brackets, casings, buttons and more. HP’s advanced technology also enables texturing.
Without the need to include support structures for the printing process, post processing can be relatively quick. HP’s 5200 Multi Jet Fusion technology includes an option for ‘Fast Cooling’, in addition to its natural cooling unit, both contributing to economic efficiency.
Parts straight off the printer for both materials are grey. They’ll be slightly rough, and there will be excess powder so the next steps to achieve a smooth finish need to be implemented. This can be achieved through bead blasting, sand blasting and water jet blasting. Paragon has invested in a DyeMansion suite, which includes Shot Peening, a process like sand blasting but using tiny particles of glass, metal or ceramics. The force of these particles against the part smooths the plastic to a unique, satin-look finish in about 10 minutes. The post processing suite also includes automated dyeing facilities offering over 170 RAL and standardised colours.
If you are interested in exploring the merits of MJF, click on the button below for a quote.