Over the last several years our supply chain has continued to shrink. We are a lot like the rest of the nation in terms of manufacturing; our industry base is shrinking because of market forces, consolidations, and lean manufacturing and a just-in-time supply base.
How does your lab determine what parts will be made of each material?
There is a set of requirements we receive during the design phase, all of which are analyzed in different aspects through the life cycle. Major material decisions have to be made early in the design phase. We need to know dimension and weight requirements; if it’s a stiffness-driven structure, then what are its loads for compression and tensile properties, and of course what are the cost and sustainability factors?
When are composite products used?
In aerospace, composites products have advantages in both thermal and lightweight structures applications. Thermal applications include ceramic matrix or carbon-carbon composites, used in high temperature areas such as a nose cone, leading edge, or re-entry heat shield. Structural composites are much more widely used and have been around for 40 years. Very little progress was made in the first 20 to 30 years, it’s only been in the past 20 or so that I’ve seen signs of substantial progress. A lot is currently being done with composites in the structural components of aviation and aerospace, such as the Boeing 787 and NASA’s new all-composites crew module.
What is NASA’s material evaluation and testing processes like?
The materials and testing process we perform are extremely technical and rigorous. The R&D phase for something like a composite part is driven by the systems levels. We make decisions early on in the process and determine what we use and how long it will take NASA to incorporate the part into our systems, which can take one to five years. At the end of the R&D process, we perform the qualification and certification for space flight. If the space flight involves humans, then the qualifications are even more rigorous.
Why has it taken people so long to adopt composites?
I would say it’s a cultural phenomenon. People only use what they know and the aerospace community especially tends to rely on conservative materials that are proven to have a high level of confidence and reliability. It takes time to change, and the biggest project driving that change today is the Boeing 787.
What current concerns do you have regarding composites?