What is aerospace grade carbon fiber?
Why is the price of this grade of fiber so high?
"Aerospace Grade" is generally regarded in the composites industry as the highest standard material in the field of composite materials, that is, the best and most advanced material in the industry. In a way, aerospace-grade composites are industry-leading, but that's not exactly what it means. "Aerospace grade" means that the material, structural member, fiber or resin system is suitable for use in aircraft.
How to Define Aerospace Classes
In the aviation sector, for example, all materials inside a commercial aircraft go through a "certification" process. The Federal Aviation Administration (FAA) has set a standardized process for all components within an aircraft to be "certified". The certified aircraft has all components of aerospace-grade materials: carbon fiber fuselage, bolts, aluminum, windows, adhesives, rivets, screws, titanium plating… . Yes, all materials are verified! Every component installed on an aircraft or aircraft engine is certified to the appropriate aviation standard, making it "aerospace grade". And these long-term certification processes have also made material prices soar!
Aircraft are loaded with precious cargo, usually but not limited to us humans. It's safe to fly in today's world because every component is paid attention to detail. The FAA's deep involvement in commercial and certified aircraft ensures quality control and precise manufacturing practices. An aerospace-grade component comes with the component manufacturer's certification document stating that it was manufactured to a certain quality standard and how it was tested to that standard.
Aerospace Grade Composites
Let's take an example of a simple carbon fiber structure that is being assembled and mounted to the wing of an aircraft. Before the part is approved for placement on the aircraft, it needs to be inspected. Specifically, the inspection will include where the part was manufactured and the manufacturer's documentation work.
A written record for traceability of that particular section. Traceable details such as where and how NDT was performed, in which autoclave the curing took place, when did the prepreg come out of storage; if any repairs were made to the part, what material was used in the repair, fabric Where did the materials come from, where did the core materials come from, what binders were added and where were they made?
Materials used to make fabrics, tapes or resins go through the same in-depth testing and certification process. Aerospace suppliers are certified for a variety of fibers, resins, cores and adhesives at their manufacturing facilities. This ensures that the manufacturer executes the process with the highest quality. The content on a given test report for a particular material is more or less "set in stone". The lab's test report did not fudge any numbers. The manufacturing process to make the material is also the same for the quantity of a specific fiber or fabric made according to a specific test method, but the process control is aerospace grade.
Occasionally one may find that non-aerospace-grade materials are stronger or cheaper than aerospace-grade materials. But it's hard to find a tested material that can reach the testing range of aerospace-grade materials. The quality assurance of aerospace-grade structural components is virtually unmatched.
Do you need it?
Aerospace-grade materials in composites often lead the industry. Big companies have the money to design the latest and greatest prepreg systems, on the other hand, aerospace-grade structural parts have been around for decades. Aerospace-grade carbon fiber fabrics, introduced in the 1980s, are still used in aircraft composite parts today. Non-aerospace-grade fabrics are produced on the market today with lamination properties similar to or better than existing aircraft. But does all this mean that a roll of non-aerospace-grade material could be used for the next spoiler build? no.
It's the same concept as putting an aerospace-grade screw on your kitchen table. Can aerospace-grade screws hold up? Yes, and probably really good. It's no big deal if your desk falls or breaks because of the screws. But the aerospace field is quite different, as a broken or missing screw can cause a huge accident. Therefore, even if there are other "non-aerospace-grade" or "conventional" fabrics and resins on the market that can meet the performance required for aircraft, aerospace-grade materials can still be sold at double or even triple the price of ordinary materials.