3D printing matures for tooling.
By Adam Broda, senior production engineering manager, Boeing Additive Manufacturing
While additive manufacturing (AM) may still feel like an experimental technology, it has matured far beyond the adolescent state of desktop 3D printers and plastic filament. In fact, today more than 70,000 3D-printed production parts fly through Boeing commercial and defense programs. The technology is evolving from research and development projects and low-cost tooling to printing high volumes of high-value metallic components and large families of tools that require stress analysis.
What will it take for AM to further mature and become more viable in production systems and product life cycles? For this discussion, let’s consider tooling and focus on scale, training and supply as key factors in the continuing maturation of AM.
Tooling at scale
Aerospace tooling can be as complicated and unique as “fly-away” parts, but the requirements to produce loadbearing tools can be far less rigorous. Parts that will fly on a plane may take several years of testing and certification to ensure safety and quality — and for that same reason, may have more rigidly defined processes for production.
With tooling, there is more freedom to create processes for design and fabrication. More latitude is provided to determine how long it should take to design and test new technologies, define tooling specifications and ultimately advance industry standards. For the last decade, several dedicated tooling teams throughout Boeing have worked to analyze and characterize cutting-edge materials, optimize new printing processes and explore new opportunity spaces for tooling design applications.
In what was once a very nonstandard field, the Boeing AM tooling community has created a methodology for developing tooling standards for a wide variety of materials and printing methods, such as high-temperature polymer materials and large-area printer qualification specifications. This methodology unifies and standardizes the ways different programs and business units apply AM and makes the process of leveraging the technology more accessible and efficient for everyone.
For example, an AM production center at the Boeing Interiors Responsibility Center (IRC) in Everett, Washington, was set up several years ago to explore large-area polymer printing systems and tooling applications. By 2020, there will be not only large-polymer production tooling in use at the IRC but also material standards for the types of plastic that they print with, as well as a qualification specification for the printer that defines and controls the quality of the products being produced. Because of this, standards structure teams throughout Boeing will leverage the experience and expertise of the additive tooling groups in the IRC and share their knowledge with other tool engineers throughout the company.
Such a model facilitates rapidly scaling the development and application of AM in the company, which is proven to be successful. In 2018, Boeing fabricated over 7,500 additive tools. That figure has already exceeded 14,000 this year.
Boeing is training users to enable them with the tools they need to do more with 3D-printing technologies, but training is more than teaching people how to apply and design with AM. Additive, like all technologies, is ultimately about value creation: understanding when to use AM to help lower costs, shorten delivery times, reduce weight and assembly, and increase quality and part durability.
To fully capitalize on AM’s potential opportunity, Boeing has created training courses and design guides to help designers, engineers and other users make these types of assessments. For example, in 2018 Boeing and the Massachusetts Institute of Technology launched an online certification course, led jointly by Boeing additive experts and MIT professors, to teach engineers how to take advantage of the potential benefits of AM. To date, more than 1,000 Boeing engineers have taken the course, as well as many more thousands of people outside Boeing.
Boeing also partnered with Washington State University on a pilot project earlier this year to provide an online AM course and hands-on learning opportunities to Boeing engineers. Shorter internal training modules have also been developed to provide targeted overviews about designing for AM, such as explaining when AM can best be leveraged to reduce cost and weight.
AM has evolved from a new technology used primarily for prototyping to a full-scale manufacturing tool in the design-for-life-cycle toolbox.
Another key to maturation will be turning cost and flow from a constraint to an advantage. As Boeing and other companies expand the capacity to produce additive production tools and parts for aerospace and other industrial applications, a corresponding supply-chain-at-scale is necessary.
With respect to both raw material purchasing and parts providers, a growing and competitive supply base of AM vendors can ultimately reduce the cost of AM fabrication while maintaining or improving quality and consistency of the production system — which will benefit the maturation of AM within industry as a whole.
Looking at additive from end to end, printing itself generally accounts for the lesser share of the total fabrication cost. As the implementation of AM has increased, Boeing has integrated raw material purchasing within its broader enterprise supply chain strategy. Consequently, cost reduction in materials such as titanium powder has been substantial.
Likewise, a growing number of qualified suppliers are beginning to create a viable AM supply base. It’s one thing for a supplier to own a 3D printer capable of printing a tool; it’s another to demonstrate that they can deliver at scale, meet rigorous aerospace specifications and tolerances, and execute with fixed and repeatable processes. Increasing industry standardization in the additive area is enabling a robust global supply chain to support the need for capable, qualified AM aerospace products.
These are, of course, not the only areas that will mature as AM grows in practice and sophistication. Additive is a highly dynamic industry with new startups and technologies making entrances frequently. There also key challenges that still need to be solved in order for higher levels of advancement to occur. The speed of laser powder-bed metal printers, for example, continues to be a constraint, and the industry is focused on increasing the number of lasers, or layer thickness, within a machine to shorten printing time. Challenges and constraints aside, AM continues to grow rapidly, and Boeing’s continued investment in the field is driving value-focused technology development and adoption. Value in the form of cost savings, time savings, design capabilities, quality and sustainability is enabling the transformation of production systems and changing the way we design and manufacture parts and tools.