• Thu. Aug 18th, 2022

New 3D printing process for printing complex parts

ByRandall B. Phelps

Aug 2, 2022

Rutgers University engineers have developed a technique for 3D printing large, complicated parts for a tenth of the price of existing approaches. The team published their findings in the journal Additive manufacturing.

Parts printed with the MF3 prototype using a 0.4mm diameter nozzle. Image Credit: Rutgers The State University of New Jersey

We have more testing to do to understand the strength and geometric potential of the parts we can make, but as long as those things are there, we think it could be a game-changer for the industry.

Jeremy Cleeman, Study Lead Author and Graduate Student Researcher, Rutgers School of Engineering

The newest technique, known as multiplexed fused filament fabrication (MF3), uses a single gantry – the moving component of a 3D printer – to print a single item or multiple parts simultaneously.

Researchers were able to increase print resolution and size and significantly reduce print time by programming their prototype to move in efficient patterns and using many small nozzles to deposit the molten material rather than a single large nozzle, as is usually the case in conventional printing.

Cleeman added: “MF3 will change the way thermoplastic printing is done.”

Cleeman said his group has filed a patent application in the United States for their new technology.

The throughput-resolution trade-off, or the speed at which 3D printers deposit material versus the quality of the final output, has been an issue for the 3D printing industry.

Although larger diameter nozzles produce more ridges and bends that need to be smoothed out afterwards, they are faster than smaller ones. This leads to higher post-production expenses.

However, smaller nozzles deposit material with a higher degree of accuracy, but existing techniques using off-the-shelf software are too slow to be economically viable.

At the heart of MF3’s innovation is its software. A software tool known as a slicer, which translates an element into “slices” or virtual layers, is used by engineers to set up a 3D printer.

To make the gantry arm work as efficiently as possible, Rutgers researchers created slicer software that calculated when to turn the nozzles on and off. The researchers said in their study that MF3’s new “toolpath strategy” can “simultaneously print multiple, geometrically distinct, non-contiguous parts of varying sizes” using a single printer.

Cleeman said he believes this technique could provide a number of benefits. One factor that simplifies potential adoption is the fact that the hardware used in MF3 can be purchased commercially and does not need to be modified.

Additionally, an MF3 printer has built-in resiliency and is less prone to costly downtime since the nozzles can be turned on and off separately, according to Cleeman. For example, a typical printer should stop printing if a nozzle malfunctions. Another nozzle on the same arm can take over for a broken nozzle in MF3 printing.

Rajiv Malhotra, Alex Bogut, Brijesh Mangrolia, Adeline Ripberger, Qingze Zou and a researcher from the University of Louisville are co-authors of the study.

Journal reference:

Cleeman, J. et al. (2022) Scalable, Flexible, and Resilient Parallelization of Fused Filament Manufacturing: Breaking Endemic Compromises in Material Extrusion Additive Manufacturing. Additive manufacturing. doi:10.1016/j.addma.2022.102926.

Source: https://www.rutgers.edu/