Unlocking the Secrets of 3D Printing
Reporter: Irina Robu, PhD
Researchers at Lawrence Livermore National Laboratory discovered interesting ways to advance the capabilities of two-photon lithography, a high-resolution 3D printing technique capable of producing nanoscale features which unleashes the potential for X-ray computed tomography to analyze stress or defects noninvasively in embedded in 3D printed medical devices or implants. Two-photon lithography stereotypically requires a thin glass slide, a lens and an immersion oil to help the laser light focus to a fine point where curing and printing occurs. The findings were published in the journal of ACS Applied Material and Interfaces.
In the paper, researchers describe cracking the code on resist materials improved for two-photon lithography and forming 3-D microstructures with features less than 150 nanometer which is better in comparison to previous techniques which build structures from ground up, limiting the height of the objects.
According to LLNL researcher James Oakdale, “In this paper, we have unlocked the secrets to making custom materials on two-photon lithography systems without losing resolution”, because the laser light refracts as it passes through the photoresist material, the cornerstone is discovering how to match the refractive index of the resist material to the immersion medium of the lens so the laser could pass through unimpeded.
Investigators can now use X-ray computed tomography as an analytical tool to copy the inside parts without cutting them open and to investigate 3D printed objects by fine-tuning the material’s x-ray absorption. The only limiting factor is the time it takes to build, so the researchers are investigating how to speed up the process.
These techniques could be used to harvest and probe the internal structure of targets for the National Ignition Facility, as well as optical and mechanical metamaterials and 3D-printed electrochemical batteries.
SOURCE
https://www.llnl.gov/news/lab-unlocks-secrets-nanoscale-3d-printing
Leave a Reply