Tobey Cordel opened his speech by expressing his excitement about the opportunity he has with NDE - there are a lot of NDE applications in the Air Force. He showed an image of the materials directorate at Wright Laboratory. 600 people work here and it is widely acknowledged to be one of the primary places in the world for material research and process developing . Recently the Lab's title was changed from Material Ceramics Division to Material Ceramics NDE Division. This organization recognized that NDE as a technology is just as important as materials technology. "That's a milestone!," he said.
Systems development, acquisition and operation.
If we look at a sequence of process, it starts with design, processing, manufacturing and finally the in-service. NDE plays a critical role in all that. The Air Force is changing its spots dramatically. At aircraft museums they are talking about aircraft that will be higher, faster, and go farther Today we are looking at older, moldier, cheaper. Those are very important changes. Look into the future and we will see even older systems. They are going to serve until the year 2030. The B-52,for example, shows an average age of 32 years. We will see an increase in corrosion detection, an important and difficult task . Also new is the issue of crack growth management.
NDI is used for manufacturing and in-service, as a part of NDE, a full spectrum technology. Aircraft is very dependent on NDE. Large areas have to be inspected quickly. We saw several graphs showing applications of the McDonnell Douglas Aerospace UT automated system, or "MAUS". This system provides a test speed of 200 sq feet/hrs. It weighs 33 lbs, 21 for the electronics and 12 lbs for the scanner. Intensive trials have been made with 10 prototypes, involving all issues, including personnel certification. The Army, Navy, and civilian parties, such as race cars at the Walt Disney Center in Indianapolis, also participated. . It's very important to test the composite complex geometries of those racing cars for driver safety reasons. Actually cost for such systems is going down thanks to use by other civilian applications. And, we get trial results very quickly.
An aircraft is a system and has a lot of parts involved in NDE. Here an example of automated inspection of high pressure turbine engine disks, an ultrasonic and an eddy current test was developed. The shape is complicated and the test was performed by use of ultrasonic squirters. There are about 30 systems in place at logistic centers. Such a system works 2-3 shifts a day 7 days a week.
For radiography, he mentioned that there are an incredible number of films used each year. Digital radiography has a lot of advantages, however it's a difficult task to digitize all those pictures. There are still some systems that use both types of radiography.
In-process measurement is a very important task. NDE can provide in-process information, that is an extremely important consideration. That's the reason his division is actually called a materials and process laboratory; these two issues are extremely linked together. If we look at new sensor developments, a height temperature transducer operating at 700° F for aircraft is being developed right now. That means that ultrasonic transducers could be directly included in a process providing data in operation that couldn't even be considered before. This could be data on consolidation or changes in elastic properties during processing, so it's actually some very new information.
Tobey Cordel mentioned that the ASM, (American Society of Materials) conference held just the "material weeks" in Cincinatti. There were 31/2 days sessions on NDI. Maybe ASNT needs to have some sessions that include processing, so that we could get more involved in that. I think that there are some changes we need to watch for.
Another important issue is non-contact ultrasonics. A lot of airplanes are now inspected by laser based ultrasonics. That includes the ability to look directly into the process, that shows again that NDE becomes a critical part of process measurement.
Of course the signal acquisition and analysis becomes difficult under a noisy production environment. There are two things we are investigating right now - can you imagine monitoring superplastic titanium which is in a hot close pressure vessel and trying to understand how it expands? The processing of fiber reinforced composites that take place in a big high pressure autoclave is another challenge. It will be very difficult to get complex data in such noisy environments.
Cordel pointed out that all this is only possible because of new computers, however we have to see the critical issue as well. Everybody knows the problems of these devices. He joked, "I remember an IBM presentation some years ago, it was said that they will make the computer as easy to use as the telephone. Yes, we did it. We made the phone a lot more complicated!" There are many people who are struggling hard while trying to enjoy Win95.
Another good example is the B22 aircraft which is about to go into production. They have very big and thick composite rotors. In the early development stages, they could not produce them. Computer tomograhy helped to solve the problems. They had to change the complete manufacturing process as the result of NDI information.
The next point is design and in-suit measurement and looking for changes in material properties, not just defects and corrosion. Cordel showed an example of acoustic microscopy which was used to investigate a single fiber under load. Debonding can be seen when the load is increased. NDI also helped to perform the push out test of a single fiber.
He pointed out the use of NDE for general In-service characterization. There is a need for sensors for smart materials and structures. Again, data acquisition in a noisy environment is important.
NDE as part of the engineering curriculum.
There is a need for establishment of NDE as an overall process. Too often, NDE is the last
thing on the list.
It adds cost, it adds time, and they won't do it. Ideally, NDE should be
integrated at the classic PhD level, as some institutions have done. There are too many people today who don't understand NDE, and some of them are doing research.
Another thing that needs to be made clear is that NDE lowers overall
costs. These are important messages - engineers coming from school
should know, "this could lower my costs."
What does ASNT do? Are we structured and motivated enough to interact with other key material societies like ASTM? What about the so-called hard science societies like APS, IEEE, MRS and what about ASEE education ? Those are some important questions for ASNT and we have to meet the challenge of developing answers. I think that NDE is a full spectrum technology - that's something we should really aggressively address.
Thank you very much.
Tobey M. Cordel
Afterwards, there was a discussion. Yosi Bar-Cohen asked Toby Cordel what he
thinks about the use of the Internet to achieve more publicity for NDE.
Cordel said that ASNT had made a homepage and this would help.
I got into the discussion, too, and said: "I understand Yosi, he has
more things than just a homepage in mind. There are many more things
that could be done for promoting NDE."
Remark.: As well during the Publication commitee meeting we had a discussion about NDT's publicity.
As soon we get Mr. Cordel's promised view sheets we will
update this page.
Tobey M. Cordel
The chief of the NDE Branch of Wright Patterson Air Force Base (AFB). Cordel's teams plan and implement Air Force NDE research and development. His NDE work is vital in keeping the military's aging fleet of aircraft flying. He has also led in the development of advanced fiber-reinforced composites.