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You can now 3D print with GLASS: Tiny, complex showcase the future of construction

  • The new technique requires a fine glass powder and a standard 3D printer
  • Heating the glass to 1,300 degrees centigrade burns away any excess material
  • Scientists have created elegant designs that are just micrometres in length 

It looks like something straight out of a fairytale yet these stunning glass sculptures haven't been sculpted or blown, but created using breakthrough 3D printing. 

The technique, which can create complex designs like pretzels or castles that are just micrometres in length, could pave the way for use of silica glass in construction.

The ability to manufacture glass in detail never seen before could change the way we use one of the oldest materials known to mankind.

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A three-dimensional structure of a castle gate printed in fused silica glass. The technique requires a fine glass powder suspended in a liquid, and a standard 3D printer

The technique requires a fine glass powder suspended in a liquid, and a standard 3D printer.

Heating the printed object in an oven heated to 1,300°C (2,300°F) burns away any excess material.

This leaves behind tiny glass particles which melt together.

These structures are smooth and transparent with features as small as a few tens of micrometres.

The new technique, devised by Bastian Rapp and colleagues from the Karlsruhe Institute of Technology in Germany, could lead to the development of more sophisticated lenses and filters. 

Objects printed in 3D are normally made from polymers.

But glass makes for an excellent printing material because it has unique optical and physical properties, the researchers said.

The technique requires a fine glass powder suspended in a liquid, and a standard 3D printer. 

Fine details are usually etched onto glass with acid but now they can be 3D printed - creating tiny works of art. 

Heating the printed object in an oven heated to 1,300°C (2,300°F) burns away any excess material - leaving behind tiny glass particles which melt together.

According to the paper, which is published in Nature, the precision is only limited by the accuracy of the printer.

Dr Rapp said creating bespoke structures from high-purity glasses is difficult owing to the need for high temperatures and harsh chemicals.

Heating the printed object in an oven heated to 1,300°C  (2,300°F) burns away any excess material leaving behind tiny glass particles which melt together. Pictured is a three-dimensional pretzel created using this technique

A microfluidic Tesla mixer cascade chip was created by the new printing technique. These structures are smooth and transparent with features as small as a few tens of micrometres

The new technique overcomes this issue by using a free-flowing silica nano-composite called 'liquid glass'.

These are then heat-treated to produce optical-quality, fused silica glass structures.

These structures are smooth and transparent with features as small as a few tens of micrometres.

Dr Rapp said two previous ways to shape glass in a 3D printing process have been demonstrated using soda lime glass heated to around 1,000°C (1,800°F) and a manual approach in which a glass filament is melted using a laser beam.

This honeycomb structure was heat-treated to produce a high optical-quality. By adding metal salts coloured glasses can be created using his method

In both cases coarse structures with high surface roughness were obtained.

His new technique produces surfaces with sufficient clarity and reflectivity for a range of optical applications.

'Glass is one of the most important high-performance materials used for scientific research, in industry and in society, mainly owing to its unmatched optical transparency, outstanding mechanical, chemical and thermal resistance as well as its thermal and electrical insulating properties', said Dr Rapp.

'However, glasses and especially high-purity glasses such as fused silica glass are notoriously difficult to shape, requiring high-temperature melting and casting processes for macroscopic objects or hazardous chemicals for microscopic features.

Honeycomb structure printed in fused silica glass was exposed to a flame of 800°C (1,470°F) showing the high thermal shock resistance of the printed glass part. The new process could allow unprecedented control over shaping of glass

'These drawbacks have made glasses inaccessible to modern manufacturing technologies such as 3D printing.'

By adding metal salts coloured glasses can be created using his method.

'This work widens the choice of materials for 3D printing, enabling the creation of arbitrary macro and micro structures in fused silica glass for many applications in both industry and academia', he said.

'This process makes one of the oldest materials known to mankind accessible to modern 3D printing techniques.'  

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