Imaginez être capable de concevoir une nouvelle pièce d’un avion à moteur sur un ordinateur, et ensuite être capable de l’imprimer. Pas le dessin ou la conception, mais la partie réelle, physique. Et pas seulement un modèle de poids léger, non fonctionnel, mais une pièce bien réelle et fonctionnelle qui pourra être installée dans un moteur.

L’Université de l’Institut de Recherche de Dayton aux Etats-Unis a reçu 3 millions de dollars de l’Ohio Third Frontier, aujourd’hui pour fournir des matériaux spécialisés pour une utilisation dans la fabrication additive, c’est-à-dire la science de l’utilisation des imprimantes informatiques afin de créer des objets fonctionnels en 3 dimensions.

L’Université de l’Institut de Recherche de Dayton collaborera avec des partenaires du programme, Stratasys of Eden Prairie, Minnesota, Prototype PolyOne et Rapid Plus Manufacturing Inc (RP + M) d’Avon Lake, Ohio, pour mettre au point de composants de moteurs d’aéronefs pour GE Aviation - qui a également collaboré à la proposition de programme - ainsi que des pièces et des composants pour ATK Aerospace Structures, Boeing, Goodrich, Honda, Lockheed Martin et Northrop Grumman.

Alors que les imprimantes traditionnelles sur papier utilisent une tête de cartouche de toner pour former des lignes de texte, en ajoutant des rangées de toner à mesure que le papier se déplace dans l’imprimante, l’impression 3-D fonctionne de la même manière. Mais au lieu de toner, cependant, une tête d’impression à déplacement libre dépose précisément couche par couche, de la matière plastique ou autre pour créer un objet solide en partant du bas vers le haut.

La technologie d’impression 3D existe depuis environ 20 ans, mais la fabrication additive dans sa forme actuelle n’a qu’environ cinq ans, a déclaré Brian Rice, chef de la division Polymères et Composites Multi-Echelle de l’Institut de recherche et chef du programme de maturation de la fabrication additive pour les matériaux avancés chez Third Frontier.

Ce grattoir à glace fonctionnel a été imprimé en 3D en utilisant les capacités développées à l’Université de l’Institut de Recherche de Dayton

"The difference is that 3-D printing is known in the industry as being used for nonfunctional prototypes or models, while additive manufacturing is being used to create usable parts for industries such as aerospace, energy, medical and consumer products," Rice said.

Additive manufacturing, which made headlines this month in the Wall Street Journal and USA Today and was named number one in Aviation Week & Space Technology magazine’s May list of "Top Technologies to Watch," is a rapidly growing manufacturing technology being touted for its cost savings and waste reduction. By 2015, the sale of additive manufacturing products and services worldwide is expected to grow to $3.7 billion from $1.71 billion in 2011, according to independent consultants Wohlers Associates.

There are a number of advantages to additive manufacturing over traditional manufacturing, such as injection molding or machining, Rice said.

"Cost savings is a major benefit, because there are no molds or tooling needed to fabricate parts. With traditional manufacturing, every time you want to make even a slight change to the design of what you are making, you have to retool or make an entirely new mold, and that gets very expensive. With additive manufacturing, you can change your design as often as you want simply by changing the design on your computer file. "You can’t make complex parts with injection molding," Rice added. "And because you can print an entire part in one piece with additive manufacturing, instead of welding or attaching separate components together as in traditional manufacturing, the finished part is stronger."

Additive manufacturing holds additional benefits, said Jeff DeGrange, vice-president of Stratasys, which owns an industrial line of additive manufacturing machines that will be used to print components for end users.

"It’s better for the environment because it reduces waste," DeGrange said. "With additive manufacturing, you only use as much material as you need for the part you’re printing. But with machining, you’re shaping objects by removing material from a larger block until you have the desired form, so there is a good bit of wasted material."

Additive manufacturing eliminates the need for bolts, screws and welding and, in some cases, reinforced polymers can be used to replace heavier materials, DeGrange added.

"Lighter parts mean greater fuel efficiency in vehicles and aircraft that use them. Another advantage is the cost savings that comes from a print-as-needed process, because you don’t need to ship parts or find a place to warehouse them," he said.

3-D printers can use polymer, metal or ceramic feedstock, but our focus will be on polymers, which is already a major manufacturing industry in Ohio, according to Rice.

"UDRI has developed a highly specialized nanomaterial that will reinforce the polymer feedstock, giving the finished product greater strength and stiffness than nonreinforced polymer. It will also make the polymer electrically conductive," he said.

PolyOne will scale-up the polymer feedstock needed for mass manufacturing, Stratasys will support the inclusion of new materials in their additive manufacturing systems, and RP+M will use its expertise in additive parts manufacturing to work with Stratasys to print and supply parts to end users, Rice said.

"We’ve created an entire supply chain designed to create Ohio jobs," Rice said. "We expect this program to result in the creation of 30 high-tech jobs in Ohio during the first three years and 85 jobs after five years."

The Research Institute will use part of the Third Frontier award to purchase a 3-D printer to demonstrate the technology, and the University of Dayton School of Engineering, which recently purchased a similar machine, will provide hands-on opportunities for engineering students to become involved.

"They will focus on research into new materials and innovation in additive manufacturing," Rice said. "It’s a boost for our program, and it will also provide those students with skills that will help them secure high-tech manufacturing jobs after graduation."

Contact :

Pamela Gregg
937-229-3268
pamela.gregg@udri.udayton.edu

Brian Rice
937-229-3016
brian.rice@udri.udayton.edu

Jeff DeGrange
952-294-3461
jeff.degrange@stratasys.com

 http://www.udayton.edu/news/articles/2012/07/3-D_printing_brian_rice.php