Thursday, 27 August 2015

MIT Unveils 3D Printing Method Using Glass Instead of Plastic

They’re calling it 3DGP for Glass 3D Printing.

Borne out of collaboration between the Mediated Matter group at the MIT Media Lab, the Mechanical Engineering Department at MIT, the MIT Glass Lab and the Wyss Institute at Harvard University, 3DGP is the first time transparent glass has been used as precursor, the “ink” in common printing parlance, in 3D printing, also known as additive manufacturing. The paper titled “Additive Manufacturing of Optically Transparent Glass” by Neri Oxman, John Klein et al. will be published in the September 2015 issue of 3D Printing and Additive Manufacturing (3DP+).

  • Using optical glass as precursor in the printing process is a first
The machine works like a conventional 3D printer, where layer upon layer of the precursor is deposited on a work surface, thereby literally building a product from the ground up. In 3DGP, the upper part of the machine is the kiln containing molten glass at up to 1100°C, which is then piped through an alumina-zircon-silica nozzle, which traces the shape to be printed in all three dimensions. The lower chamber anneals the constructed structures.

The process is laser precise and could pave the way for fundamentally changing how glass and related objects are manufactured, the most obvious example being fibre optics, made with higher accuracy and lesser expense, which might be integrated into other surfaces or fabricated materials. This will enable them, for instance, to be incorporated in building construction, such as in precast walls or glass façades, the latter of which can now be created in unimaginable shapes. Also under consideration are printable optoelectronics and photonics.

  •  Printed architectural structures incorporated with fibre optics and optoelectronics a possibility
The accuracy with which the thickness and shape of the glass can be controlled is significant: geometrical variations can be used to generate desired forms of transparency, reflectivity, refractivity and various other properties.

With cutting edge research and indigenous processes and methodology at stake, people are understandably unwilling to reveal the nitty-gritties of the process. Extruder manufacturer Micron3DP, with a similar glass 3D printer in development, has been equally reluctant to share information, except that their printhead can reach temperatures up to 1640°C.

  • Details about the printing process and glass composition are closely guarded
Although the products of 3DGP have only been novelties until now, the group at MIT will soon begin to print various other geometrically complex structures, chiefly those with architectural applications. And like with any case of 3D printing, the bespoke nature of the work means maximum compatibility with each and every application.

Intricate glass work has always remained outside the domain of mechanisation; manual work by master glassblowers has been the way to go. How this new technology might clash with the age-old practice remains unknown. 3D printing might breach new frontiers of adhesion between layers, lack of light distortion, clarity, and most importantly, indistinguishability. Complex patterns created by hand will never be identical to the previous case. 3DGP and its competition do not suffer from this drawback; they can create identical products over and over.

  • Glass-blowing: an art on the way out?
3D printing might also enable creation of new shapes and structures that might have been impossible to fashion by hand, whether due to weight or other restrictions.