The multiple initiatives launched in record time by 3D printing players around the world since the start of the Covid-19 crisis were on everyone’s lips on June 25, at the Additiv digital trade show. For the participants in this event, organized by the professional media 3DNatives, the confinements and shutdown of many industrial sites highlighted the advantages of additive manufacturing. A finding that many hope to see play in favor of a greater adoption of the process.
According to the latest annual study by Sculptéo, a subcontractor specializing in the supply of 3D parts, published in early June, the production of finished parts made in additive manufacturing has increased significantly in the industry for five years. The proportion of users surveyed who said they used this technology in a production setting increased from 17% in 2015 to 52% in 2020.
However, 3D printing is still groping to find its marks in medium and large series. It is moving more towards niche uses, in which the process brings added value, whether in terms of the functionality or properties of the part, or the organization of the production chain in order to respond quickly to a need.
During a series of conferences, machine builders, members of design offices, material suppliers and manufacturers shared their experience in the successful establishment of production in additive manufacturing – polymer or metal – as well as the ways improvement to further integrate the process into the industrial sector.
Take into account the value chain from conception
A round table on the design of the parts thus highlighted the need to “ review the way we think of a room “, Says Marc Desbois, head of the 3D printing program at Michelin. ” There is a change of mindset – of mentality – to acquire. The entire object value chain must be taken into account when designing. It’s not a given for design teams “, He adds.
The Michelin group, which has been printing mold inserts for its tires since 2016, has chosen to highlight a design that prioritizes the reduction of the number of operations required on the production chain. ” It’s a very strong lever for us. We got into printing to look for shapes that we couldn’t do with traditional methods, essentially to gain performance on the product. But there is also the economic aspect that we have to balance. Switching to 3D printing has a cost, especially in terms of equipment, but it can be offset by gains on other positions in the production chain. “
A point of view shared by Pierre Kraus, director of the company Aereco, which produces ventilation systems. ” From the CAD stage, you have to take into account the overall cost of the object “, He explains. The company that produces polymer parts using the Multijet Fusion process developed by machine manufacturer HP optimizes its costs by maximizing the number of parts in the production volume. ” We have redesigned the design of some pieces so that they fit perfectly on the printing plate. We take advantage of all the space available for our parts. », Specifies Pierre Kraus. This so-called “nesting” technique thus reduces cycle times and “ cut costs in half on certain parts “
More surprisingly, Aereco also produces parts of small dimensions in the form of “clusters”, similar to the kits of the reduced models whose elements must be detached before assembling them. If this arrangement is natural in the plastic injection process, where the molten polymer is injected into cavities connected by channels, thus creating injection “cores” which must be removed, its use in the context of manufacturing additive meets a specific expectation: ” We thus have them to facilitate post-processing operations. The cluster allows for example to paint all the parts at the same time or even to submit them in one piece to finishing operations, such as sanding. We then detach them from their support. “
Three stages in the optimization of a satellite structure: on the left the original part, in the center the part after a simple topological optimization, on the right after topological optimization and addition of additional functions (new fixings).
Explore the potential of new materials
The importance of design is also gaining importance with the arrival of new high performance materials, including thermoplastics with PEEK (polyetheretherketone) and PEKK (polyetherketoneketone). ” These materials can replace metal in certain applications “Explains Yannick Willemin, development manager at 9T Labs,” They are still relatively new in the field of 3D printing. We must learn to master them and better understand their behavior during printing but also during the post-processing stages. ” At Dassault Aviation, the passage of certain parts from metal to polymer is underway. But the aircraft manufacturer prefers to play the caution card.
” We assess on a case-by-case basis, during re-evaluation campaigns, whether parts are eligible for a new production method or a new material.Explains Alexandre Ellies, technical manager at the Dassault Aviation exploratory development center.
Composite materials are also closely monitored, in particular carbon fiber-filled resins, the incorporation of which in certain parts could save weight while offering great mechanical resistance. However, the process for printing composites, even if it is starting to be proposed by certain printer manufacturers, in the form of deposition of high performance polymer yarn loaded with short fibers, is not yet capable of industrially producing large parts loaded with continuous fibers. ” It is a complex technique that requires precise placement of fibers and layers of resins. She still needs to mature “, Says Alexandre Ellies.
Faced with numerous technologies, define standards
Finally, the issue of standardizing the parts produced by additive manufacturing is essential for the industrialization of parts, in particular to facilitate relations with subcontractors. In fact, in the field of metal 3D printing, many manufacturers have chosen not to integrate the often very expensive equipment and to entrust production to subcontractors specialized in this technology.
” When asked “make or buy?”, We chose the “buy” option. Printing metal parts by laser fusion on a powder bed requires very heavy equipment for operator safety. So, for the moment, we are outsourcing production. ”, Points Aurélien Fussel responsible for additive manufacturing at Alstom, which has had a program dedicated to metal and polymer additive manufacturing since 2016. But with a wide range of technologies available and brands of printers with various characteristics, it is imperative for manufacturers to qualify this equipment and establish production standards related to additive manufacturing.
Alstom has thus organized itself around a “hub” of skills in 3D printing, which irrigates and puts in tune with the other divisions of the group in terms of good practices. ” We are upgrading all of our technology design offices. We qualify the subcontractors to ensure that the parts meet the requirements of the sector, whether for the SLM process or for the metal arc deposition process (WAAM) that we are developing. “, Supports Aurélien Fussel.
The same goes for the European Space Agency (ESA), which has been interested since 2003 in the 3D printing process to lighten and reduce the number of parts in satellites. ” We fund many partners in this area“, Highlights Laurent Pambaguian materials engineer at ESA” The European agency is responsible for standardization in the space sector. So we have started a major project to establish a standard related to additive manufacturing in our sector. We do this with the help of “Large System Integrators”, that is to say the main satellite manufacturers “.
While there are still many challenges for the industrial production of parts in additive manufacturing, the participants of the day welcomed the speed with which skills are spreading from one sector to another. ” We have an advantage at ESA: whenever industry has a problem, it comes to talk to us about it. We quickly develop skills in transverse ways, from the supply of the powder to the final validation of the part. We share information “Explains Laurent Pambaguian.
A point of view shared by Anne Debauge, director of digital at l’Oréal. ” In 3D printing, iThere is real cross-fertilization between the sectors. We learn a lot from other industries. We tend to evolve into an ecosystem around technology and this allows us to go fast “