This image shows cells adhering to a titanium alloy created by cold-spray 3D printing, which demonstrates the material’s biocompatibility.
Forget glue, screws, heat or other traditional bonding methods. A Cornell-led collaboration has developed a 3D printing technique that creates cellular metallic materials by smashing together powder particles at supersonic speed.
This form of technology, known as “cold spray,” results in mechanically robust, porous structures that are 40% stronger than similar materials made with conventional manufacturing processes. The structures’ small size and porosity make them particularly well-suited for building biomedical components, like replacement joints.
The team’s paper, “Solid-State Additive Manufacturing of Porous Ti-6Al-4V by Supersonic Impact,” published Nov. 9 in Applied Materials Today.
The paper’s lead author is Atieh Moridi, assistant professor in the Sibley School of Mechanical and Aerospace Engineering.
“We focused on making cellular structures, which have lots of applications in thermal management, energy absorption and biomedicine,” Moridi said. “Instead of using only heat as the input or the driving force for bonding, we are now using plastic deformation to bond these powder particles together.”
Moridi’s research group specializes in creating high-performance metallic materials through additive manufacturing processes. Rather than carving a geometric shape out of a big block of material, additive manufacturing builds the product layer by layer, a bottom-up approach that gives manufacturers greater flexibility in what they create.
However, additive manufacturing is not without its own challenges. Foremost among them: Metallic materials need to be heated at high temperatures that exceed their melting point, which can cause residual stress buildup, distortion and unwanted phase transformations.
To eliminate these issues, Moridi and collaborators developed a method using a nozzle of compressed gas to fire titanium alloy particles at a substrate.
“It’s like painting, but things build up a lot more in 3D,” Moridi said.
The particles were between 45 and 106 microns in diameter (a micron is one-millionth of a meter) and traveled at roughly 600 meters per second, faster than the speed of sound. To put that into perspective, another mainstream additive process, direct energy deposition, delivers powders through a nozzle at a velocity on the order of 10 meters per second, making Moridi’s method sixty times faster.
The particles aren’t just hurled as quickly as possible. The researchers had to carefully calibrate titanium alloy’s ideal speed. Typically in cold spray printing, a particle would accelerate in the sweet spot between its critical velocity – the speed at which it can form a dense solid – and its erosion velocity, when it crumbles too much to bond to anything.
Instead, Moridi’s team used computational fluid dynamics to determine a speed just under the titanium alloy particle’s critical velocity. When launched at this slightly slower rate, the particles created a more porous structure, which is ideal for biomedical applications, such as artificial joints for the knee or hip, and cranial/facial implants.
“If we make implants with these kind of porous structures, and we insert them in the body, the bone can grow inside these pores and make a biological fixation,” Moridi said. “This helps reduce the likelihood of the implant loosening. And this is a big deal. There are lots of revision surgeries that patients have to go through to remove the implant just because it’s loose and it causes a lot of pain.”
While the process is technically termed cold spray, it did involve some heat treatment. Once the particles collided and bonded together, the researchers heated the metal so the components would diffuse into each other and settle like a homogeneous material.
“We only focused on titanium alloys and biomedical applications, but the applicability of this process could be beyond that,” Moridi said. “Essentially, any metallic material that can endure plastic deformation could benefit from this process. And it opens up a lot of opportunities for larger-scale industrial applications, like construction, transportation and energy.”
The Latest Updates from Bing News & Google News
Go deeper with Bing News on:
- 'The trial is stupid': Senate Republicans throw cold water on Trump impeachmenton January 24, 2021 at 12:00 pm
Several Republican senators Sunday discouraged suggestions that the chamber could convict former President Donald Trump in his impeachment trial. "Well first of all, I think the trial is stupid," Sen.
- Here are the best ‘Cold War’ weapons in ‘Warzone,’ according to expertson January 23, 2021 at 3:50 pm
The semiautomatic rifle became one of the most powerful weapons ever introduced into “Warzone,” and quickly defined the meta. Everyone had to run one because it could kill with as few as two shots, ...
- Long Island weather: Cold and blustery weekend, snow early next weekon January 23, 2021 at 3:48 am
Brace for a markedly cold and blustery weekend and Monday — and then a touch of snow starting that night. "At this time the precipitation begins Monday evening and continues into early Tuesday evening ...
- Latest weather outlook for Bucs-Packers playoff game Sunday: cold, snow, freezing drizzleon January 22, 2021 at 10:56 am
While cold weather and snow are likely, Tampa Bay Head Coach Bruce Arians says it's not the forecast he’s most concerned about.
- The best Call of Duty: Black Ops Cold War Diamatti loadouton January 20, 2021 at 12:03 pm
If you're a fan of handguns then Black Ops Cold War is the CoD for you. And amongst its several broken pistols, the Diamatti reigns king.
Go deeper with Google Headlines on:
Go deeper with Bing News on:
3D printing biomedical components
- Scientists use a novel ink to 3D print 'bone' with living cellson January 25, 2021 at 6:40 am
D printers may one day become a permanent fixture of the operating theatre after UNSW scientists showed they could print bone-like structures containing living cells.
- Mighty Morphing 3D Printing: New Shape-Changing Nozzle That Could Revolutionize “4D Printing”on January 23, 2021 at 10:43 pm
Engineers at the University of Maryland (UMD) have created a new shape-changing or "morphing" 3D printing nozzle that was featured as a Frontispiece in the January 5th issue of the journal Advanced ...
- 3D Bioprinting Market Expected to Grow at CAGR 31.25% and Forecast to 2024on January 22, 2021 at 10:18 am
Jan (Heraldkeepers) -- 3D Bioprinting Market is valued at around USD 484.50 Million in 2019?and is evaluated to achieve USD 3250.60 Million ...
- Bugatti Devises Innovative Method to 3D-Print Titanium Components for the Bolideon January 22, 2021 at 2:37 am
After taking the notion of a track-oriented supercar to another level, Bugatti aims to do the same with lightweight titanium components using an innovative 3D printing process.
- 3D Printing Medical Devices Market Size | COVID-19 Impact Analysis | Forecast to 2025on January 21, 2021 at 12:59 pm
The global 3D printing healthcare market has witnessed dynamic growth within the recent years, due to rapid technological advancements, rise in investments in R&D activities, and rapid expansion of ...