3D Printable Syntactic Foams Could Help Submarines Reach Deeper Depths

A team of researchers from New York University School of Engineering have developed 3D printable syntactic foam materials. These foams are lightweight composites that offer exceptional buoyancy and strength, and are commonly used for submarine components. 

Scientists at the New York University Tandon School of Engineering have developed the first process to produce 3D printed components from syntactic foams. This industrial-grade material is a lightweight composite that is commonly used for functional parts in airplanes, automobiles, and even submarines.

The researchers believe that their filaments could offer significant advantages for industries where parts are needed to withstand stress at greater depths. The newly developed syntactic foams are comprised of high-density polyethylene plastic (HDPE)–which is a material used to manufacture industrial-grade parts–and microspheres made of recycled fly ash.

Traditionally, engineers have had to use injection molding to create components from syntactic foam. To connect different syntactic foam parts together, they’ve also had to utilize adhesives and other fastening methods, which can lead to glaring vulnerabilities in the part design.

The 3D printable syntactic foams are made from a mixture of billions of microscopic hollow glass or ceramics embedded in an epoxy or plastic resin. This material type provides incredible buoyancy and strength, and is oftentimes used in submarines, such as James Cameron’s famous Deepsea Challenger.

Additionally, the 3D printable syntactic foam materials can be used to produce parts as a single unit rather than in separate pieces, which adds to the overall stability of components.

3D Printable syntactic Foam Provides Exceptional Strength to Functional Parts

The team, led by Nikhil Gupta, an associate professor of mechanical and aerospace engineering at NYU, tested the new syntactic foam filaments using a commercial 3D printer. The researchers also discovered that the filaments are recyclable, making them more environmentally friendly.

“Our focus was to develop a filament that can be used in commercial printers without any change in the printer hardware,” explained Gupta. “There are a lot of parameters that affect the printing process, including build-plate material, temperature, and printing speed. Finding a set of optimum conditions was the key to making the printing of high-quality parts possible.”

He added that the hollow spherical particles used in the study were just 0.04 mm to 0.07 mm in diameter. At this tiny scale, the particles will not clog up the 3D printer nozzle. They also had to minimize crushing the hollow particles in order to keep the resin materials at a low density.

Ashish Kumar Singh, a PhD under Gupta, elaborates on this process:

“We want to add as many hollow particles as possible to make the material lighter, but having a greater number of particles means more of them will break during processing. The survival of hollow particles first during filament manufacturing and then in the 3D-printing process requires a lot of process control.”

The resulting 3D printable foams demonstrate exceptional strength and density when compared to similar parts made with injection molding. According to Gupta, the team will now shift their focus towards optimizing the material properties for various applications, such as underwater vehicle components that are capable of properly functioning at specific depths.

The findings have recently been published in the Journal of the Minerals, Metals & Materials Society.

Source: NYU Engineering