Page 27 - 3D Metal Printing Winter 2018

This advanced turbo prop (ATP) for a Cessna Denali aircraft by Textron Aviation, Wichita,
KS, represents the
efforts of hundreds of
GE Additive
engineers, 35
percent additive
content and a huge
parts-count
reduction—from 855
subtractive-
manufactured parts to
just 12 additive-manufactured parts.
stiffness strength where it’s needed to improve aerodynamics, while lowering the weight of the case.” Additive ATP com- ponents made from titanium, cobalt chromium and nickel-based alloys result- ed in a 5-percent weight reduction.
Lessons Learned from Nature
Many of the design lessons learned and applied during the project were inspired by nature, says Mook. In other words, biomimicry—the design and pro- duction of materials, structures and sys- tems modeled on biological entities and processes, as defined by Oxford University Press.
“We looked for ways that nature accomplishes what it needs to do,” says
Mook. “For example, we studied animals and the way they’re designed when it comes to cell structure and cell walls. It’s amazing how those structures are designed for strength where strength is needed most. We took what we learned from studying cell structures in nature, and we applied that to developing the complicated grid-like patterns found throughout the engine design.
“Biology essentially solves the stress and strain equation and always in the most efficient manner,” he continues, “moving way beyond fixed shapes and resolving shapes to fit the function. We can, and do, apply these lessons to topol- ogy optimization when it comes to parts and simulation design.”
Future Is Bright
Mook says that GE Additive uses a combination of propri- etary “homegrown” software. Its recent acquisition of Belgium-based GeonX, provider of simulation soft- ware, will enable GE Additive to continue development of aerospace applications for metal AM, as well as medical, power
generation and automotive.
The ATP project follows on the heels
of the company’s successful development and production of complex additive fuel- nozzle interiors for LEAP jet engines by CFM International, a 50/50 joint company of GE and Safran Aircraft Engines of France.
Last November, more than 11,000 LEAP engines were on order, and it was reported that GE would produce about 6000 of the fuel-nozzle injectors in 2016, growing to 12,000 in 2017 and 35,000 annually by 2020, using more than 50 machines at its manufacturing facility in Auburn, AL. Meanwhile, the company recently announced plans to build a factory out- side of Prague, Czechoslovakia, for pro- duction of the ATP engines.
Mook says that GE is taking what it has learned from its jet-nozzle and ATP suc- cesses to develop training courses to teach engineers how to design to the additive process, and that future additive efforts will involve more inhouse industrial designers. “I don’t think we understood early on the value of merging industrial design with engineering additive solutions,” says Mook. “Now the engineers are involved and reg- ularly consult on an as-needed basis.
“What we’ve been able to do,” he con- tinues, “is develop an ecosystem around additive design and additive manufactur- ing. We’ve learned a great deal and now we’re making available our methodologies and consulting expertise to other com- panies as part of our GE AddWorks busi- ness. Our teams of engineers, scientists and industrial designers can help jump start companies looking to pursue addi- tive. This is a full-service program, com- plete with machines, materials and engi- neering expertise. It’s about shared successes in additive.” 3DMP
3D
GE Additive engineers at work on the advanced-turbo-prop project. Innovation Leader Josh Mook says GE is “unlocking the mindsets of engineers” when it comes to embracing additive manufacturing.
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