3D printers are able to produce parts more accurately and at a faster rate than ever before. A plastic acoustic guitar, 3D printed medical models, lightweight parts for aircrafts and cellphone cases are just some of the things this technology has helped create.
The options of what can be created are constantly being challenged by companies and education providers.
Universities such as Deakin University and the University of South Australia are taking up the chance to be a part of this ever-growing industry. Deakin University, for example, has a 3D printing lab in which students can use the latest in polyjet and fused deposition modelling technologies. And it’s not just plastic models that are being transformed from a picture on a computer screen to a tangible object.
Swinburne University is working on the development of 3D printing concrete, and companies such as Air Liquide are working on improving the printing of metals.
Director of Swinburne’s Centre for Sustainable Infrastructure, Jay Sanjayan, is leading a $1.3 million collaboration between seven Australian universities to develop 3D printing of concrete. Having announced the project in mid-2018, he said construction remains largely manual work, which makes it expensive, and makes the global need for housing and infrastructure very hard to meet. “Construction is open to be disrupted by automation, and 3D printing is one technology that can help.”
Although 3D printers are commercially available for manufacturing, there are significant differences between printing small parts and printing parts too large to fit in a building, which is where the research comes in handy.
“Rather than factory conditions, we have to print out in the weather. Instead of a few kilograms of materials, we have to handle tonnes. Although we don’t need the same accuracy as the aerospace industry, we have to trade that for low cost,” said Sanjayan.
The options the group has explored include powder-bed 3D printing, in which the printer spreads a thin layer of concrete powder, then prints a water-based ink that sets the concrete where the ink is applied. Layer by layer, the process is repeated.
As with layers in the printing process, Air Liquide knows there are many layers that can improve 3D printing and the value it brings to the manufacturing sector. The company supplies manufacturers with gases, technologies and services, and with continuous research into 3D printing, it aims to help manufacturers get better results.
Centre for collaborative work
Air Liquide is present in 80 countries, including Australia. In November 2018 the company established an Advanced Fabrication Centre in the US. Air Liquide Australia marketing manager Arnaud Voisin said it would be the first research and development platform in the Air Liquide Group dedicated entirely to advanced manufacturing. “In addition to our multiple research programs with partners in Europe, such as the Additive Factory hub in collaboration with Safran, this new centre will help us better understand the impact of the atmosphere in metal parts manufacturing.
“We want to improve understanding of something that is to some extent underestimated today in 3D printing, because most people have been focusing on the metal component, but the atmosphere is also very important. When you want to manufacture not just one or two pieces, but rather many pieces, you need to master all of your parameters,” said Voisin.
Air Liquide looks at how the powder in 3D printers can be best manufactured, utilised and recycled for better outcomes. The company can help define the most suitable gas quality and flow parameters during the printing process. It can help with treating and cleaning of 3D-printed parts and it can help improve the overall safety of the printing process.
The new centre, located in the premises of Air Liquide’s existing Delaware Research and Technology Centre, is devoted to joint development of technological solutions in the area of fabrication processes, spanning 3D printing to welding solutions to research on laser and plasma cutting technologies. It has a dedicated space designed for collaboration with equipment manufacturers to better meet the needs of end-users. With an international network of experts, Air Liquide supports customers everywhere in the world in getting the best combinations between gases and process parameters.
Air Liquide also helps in the post-processing side of 3D printing and it continues to develop improved techniques in heat treatment. Once an object has been printed, the parts need to be smoothed out. “Besides tempering, one of the processes that is used is called HIP (Hot Isostatic Pressing), in which the whole part is pressed together with very high pressure of argon in a chamber at high temperature. It prevents porosities and it complies with the higher end specifications for aerospace, for instance.
“The heat treatment of the printed parts is an essential step to obtain the desired mechanical properties and once again, the gas used and atmosphere parameters play an important role in this process” said Voisin.
Keeping processes clean
“When it comes to 3D printing, cleaning processes also need to be considered to remove remaining metal powder and get required surface states. Air Liquide’s CO2 snow and dry ice cleaning solutions efficiently remove powder residues, while minimising the usage of solvents.
“CO2 cleaning requires minimal investment, is more eco-friendly and demands less process steps than the traditional wet cleaning. It is widely used in advanced manufacturing industries and is well adapted to the cleaning of 3D-printed parts,” said Voisin.
Air Liquide also provides gas solutions to many other industries, notably in food and beverage processing, water treatment, lab analysis and healthcare.