LLNL scientists use 3D bioprinting to better understand cancerous tumor formation

Lawrence Livermore National Laboratory (LLNL) researchers have combined 3D bioprinting with computational flow simulations to better understand the spread of cancer during metastasis.  Working alongside scientists from Duke University, the team injected tumorous cells into a 3D printed brain cell structure. By applying fluid dynamics analysis to the process, the team were able to identify […]

Brookhaven scientists use kebab-like structures to advance FFF 3D printing

Researchers from the Department of Energy’s Brookhaven National Laboratory (BNL) have devised a method of better understanding the Fused Filament Fabrication (FFF) 3D printing process.   Working with a team from Stony Brook University, the Brookhaven scientists developed a dual-scanning method, which enabled them to monitor material deposition during 3D printing in real-time. While testing their approach, […]

EOS and BASF 3D printed designs awarded $1.37m NFL Helmet Challenge funding

The National Football League (NFL) and Football Research Inc. (FRI) have awarded $1.37 million in funding to groups developing 3D printed protective headgear for the ongoing NFL Helmet Challenge.  Additional finance has been provided to four different projects, in order to aid the creation of their innovative helmet prototypes. With the help of well-known additive […]

Researchers successful in reducing spatter-induced defects in metal 3D printed parts

A team of researchers from Lawrence Livermore National Laboratory (LLNL) have discovered a way of reducing defects in metal parts 3D printed via LPBF. By carefully controlling the ‘spatter’ of rogue material launched out of the powder melt track, the scientists were able to significantly reduce loose powder interaction with freshly fused material, increasing the […]

Nanofabrica raises $4m in investment round led by Microsoft-backed M12 and Nextleap Ventures

Nanofabrica, the Israeli developer of precision additive manufacturing technologies, has raised $4m of investment in a funding round led by Microsoft’s venture arm M12 and venture capitalists NextLeap Ventures.  The latest round of funding takes the total raised to $7m, which will be used to further the company’s research and development goals, in addition to […]

UC Riverside to lead scalable quantum computing project using 3D printed ion traps

UC Riverside (UCR) is set to lead a project focused on enabling scalable quantum computing after winning a $3.75 million Multicampus-National Lab Collaborative Research and Training Award. The collaborative effort will see contributions from UC Berkeley, UCLA and UC Santa Barbara, with UCR acting as project coordinator. Scalable quantum computing Quantum computing is currently in […]

Insights from 3D Printing and AM experts heading to the RadTech 2020 UV+EB Technology Conference

From March 8-11, 2020, the RadTech 2020 UV+EB Technology Conference will showcase advancing ultraviolet and electron beam technologies for 3D printing and additive manufacturing.  Set to take place at Disney Coronado Springs in Orlando, Florida, the biennial conference, now in its 17th edition, combines cutting edge material and chemistry developments with insights from leaders across […]

Germanium, Silica & Titanium Lend Stability to 3D Printing Optical Glass

In the recently published ‘Sol-Gel Based Nanoparticles for 3D Printing of Optical Glass,’ Peter Palencia and Koroush Sasan of Lawrence Livermore National Laboratory are innovating further in the realm of high-performance optics, using 3D printing and printable titanium-germanium-silica inks made from colloidal sol-gel feed stocks.

Although glass is such a valuable material to scientists attempting to transmit, refract, and reflect light, Palencia and Sasan point out the many challenges in using it for work like theirs. For this study, they focused on a ternary formulation of core-shell SiO2 nanoparticles coated with a TiO2 shell and GeO2 nanoparticles that could be used as a feedstock for direct ink writing (DIW) lenses.

“At the atomic level, the refractive index of glass can be adjusted to a certain value based on the composition of oxides within the glass. For example, sodium oxide and titanium oxide can be added to the glass to increase the refractive index,” explain the authors. “However, the introduction of the different dopants into the glass create potential problems as they not only drastically change the optical properties of the glass, but also its thermodynamic stability and overall viability to form a transparent glass.”

With additive manufacturing processes, a new and ‘revolutionary approach’ allows for the creation of a wide range of materials, whether researchers are using cells in tissue engineering or printing with resin.

“Although these methods have seen success in the production of other materials, a robust method to 3D print an optical lens has not been developed,” stated the authors.

Bubbles are a typical challenge—resulting in stress, which then causes cracking. Other methods have not been fully researched—such as glass created via UV curable ink. In previous research by the authors, however, using fumed silica, they had some success but still found it to be ‘an inconsistent mixture that affects all aspects of the glass.’ It tends to cluster together too, creating pieces too large for extrusion. Here, the researchers found a solution in eschewing fumed silica and replacing it with sol-gel based silica nanoparticles. It can be used for direct ink writing:

“Its transparency, refractive index, and coefficient of thermal expansion is comparable to a commercial lens,” stated the authors.

The authors found that to create functional optical glass, they had to rely on a combination of germanium, silica, and titanium. The dopants (germanium oxide and titanium oxide) caused an increase in the refractive index, while still upholding functionality and performance.

In contrast to the previous use of silica inks, the new mixture promoted stability, while great care still had to be taken during heating to avoid stress cracks.

The preparation of GeO2-SiO2-TiO2 consists of four main stages

“By varying the concentration of GeO2 and TiO2, we tested the viability of glass in terms of transparency and printability,” concluded the researchers. “The glass was transparent up to 7 mol% TiO2 and 14 mol% GeO2. Also, a higher colloidal stability of the glass could be seen through the zeta potential of the nanoparticles.

“While these glasses are not completely crack-free, a range of temperatures were identified as cause of cracking. Experiments to optimize ternary glass through the addition of surfactants and to reduce cracking during heat treatment are ongoing.”

3D printing is often used in optics, from micro-optics to 3D laser lithography, to embedded geometrics. What do you think of this news? Let us know your thoughts! Join the discussion of this and other 3D printing topics at 3DPrintBoard.com.

[Source / Images: ‘Sol-Gel Based Nanoparticles for 3D Printing of Optical Glass’]

 

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LLNL researchers use X-ray imaging to mitigate defects in metal 3D printed parts

Scientists at Lawrence Livermore National Laboratory (LLNL), SLAC National Accelerator Laboratory (SLAC) and Ames Laboratory are researching X-ray imaging to examine metal parts during the laser powder bed fusion process. The research paper is part of a partnership between the laboratories to identify the causes of defects in metal 3D printed parts and understand how those flaws […]

GE and LLNL to develop commercial multi-beam metal 3D printer

Under a project funded by national 3D printing development partner America Makes, Lawrence Livermore National Laboratory (LLNL) is developing a commercial-grade, metal additive manufacturing system. Designed and built in collaboration with GE Global Research, the aim of the project is to develop a platform that could cut metal processing times in half. A research-grade, open-architecture metal 3D […]