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Feats of Strength: The Coed and the Defensive Lineman
Years ago, in my junior year in college (University of Michigan), I took a materials and metallurgy class. It was the distribution class for engineers not specializing in materials and metallurgy. (My major was naval architecture and marine engineering. The class was also populated with civil engineering, chemical engineering, aerospace engineering, and electrical engineering majors.)
For most of us it was our only exposure to the mysteries of metals. It was a two-credit course, which met Tuesdays and Thursdays. While interesting, most of us were there because it was a requirement for graduation.
That did not diminish the enthusiasm of the professor – who was really into his subject. He viewed the class as an opportunity to recruit more students into materials engineering. (He would have been more successful if it were a sophomore-level course. By the time we were juniors we had enough invested in our majors – most of which was not transferable if we switched majors – to make a change unattractive.)
He was big on in-class demonstrations of the day’s topic. One day the topic was strain hardening (or work hardening). Many metals form a uniform matrix of atoms in pure form. If you take a chunk of copper, heat it up, and let it cool down slowly, the chunk cools into a single giant crystal. That makes the piece ductile, easy to bend. If you bang on the chunk, the matrix deforms. This creates smaller crystals within the piece. Suddenly it does not bend as easily. The crystals tend to be irregularly shaped, and when two crystals rub against each other they stick.
Apply enough force and the crystals break into more crystals, also irregularly shaped, which makes it still harder to bend. Work a piece of metal enough and eventually it breaks along the crystal boundaries. You can test this yourself with a tab-top on a soda or beer can. It is easy to bend the first time, gets harder to bend each time you bend it back and forth (strain hardening) and eventually breaks off.
That was the lecture he gave us one Thursday. He finished it with a practical demonstration. Throughout the talk, a one-inch-diameter copper rod, roughly three feet long, sat on his lectern. Just before the class ended, he announced he wanted to give a demonstration of strain hardening, and held up the rod.
He then asked a coed to come up to the front of the classroom. Call her Miss Jones. (This was far enough back in time, the mid-1970s, when a college professor could still refer to a female student as a coed – and address her as Miss – without being sent to reeducation camp.) Women engineering students were still fairly rare back then. Of a class of about 35 students, six were female. Jones was not the largest woman in the class. Although healthy, and probably into athletics, she was on the small side.
The professor gave her the rod and asked her to bend it as far as she could, like a pretzel, if possible.
She took the rod and pulled the ends. She finally gave up at about a 75-degree bend. The professor asked her to describe what it was like. She said the first 30 degrees of bend was easy. The next 30 were a strain, but she could not move it much past that. He thanked her and had her return to her seat.
One of the members of the class was on the University of Michigan football team. He was not a first-string player. I think he was third-string in his defensive line position, but he was on traveling squad. Although he had a football scholarship, yes, he was a legitimate engineering student. This was back in the days when you still could be a football player and a student at a top-20 school, at least at Michigan. He was using the scholarship for a free engineering education, not an NFL career. Let’s call him Mr. Smith.
After Miss Jones sat down, the professor said, “Mr. Smith, would you come up here and straighten the rod?” Smith knew he was being set up, but gamely he tried to straighten the rod. He failed of course. I think he opened it a degree or two. The professor thanked Mr. Smith and ended with a few words about how we had seen a practical demonstration of strain hardening, and ended the class.
The next Tuesday, the bent rod was on the lectern again. The professor started out by saying that after thinking about it over the weekend perhaps he had been unfair to Mr. Smith. You could generate greater strength by moving your arms together than by moving them apart. He invited Miss Jones to the front of the class again and asked her to straighten the rod.
She protested that if Mr. Smith could not do it, it would not be possible. But the professor asked her to try anyway. She picked up the rod, pulled the two ends apart – and (to her astonishment) pretty well straightened it out.
Smith was then asked to come up and bend it. He figured out what was coming, but a football player from the Bo Schembechler era did not give up. He took the rod, and tried mightily. Muscles bulging, he bent it a few degrees.
“Does anyone want to tell me what happened?” the professor asked.
After a minute of silence, someone said, “You annealed it.”
Of course, that is exactly what happened. Before the first class he had put the rod in an annealing oven, heated it red-hot, then let it slowly cool. This eliminated the grain boundaries. The rod cooled to one giant uniform matrix, allowing a fairly weak member of the class to easily bend it. Bending it created enough crystal boundaries that one of the strongest members of the class could not bend (or unbend) it further. After the first day he had popped it in the oven again, and let it cool from Thursday afternoon to Tuesday morning, ensuring it would form a uniform matrix.
It was a demonstration possible only because of the five-day wait, but was one everyone in the class remembered.
Published in Group Writing
Interesting. The way material responds to external forces is interesting. I did not go through engineering school, but had some college physics and statics classes. The one I remember the best was a basic engineering for architects class because we learned about calculating loads, determined moments, shear, bending, and looked up materials that had at least the minimum section modulus and moment. It was a practical class. My book from it is held together with rubber bands (a little purple Wiley book by Parker/Ambrose) and I still get it out from time to time.
Excellent object lesson. He was probably a great teacher.
I have a book on boat design (Prelimary Design of Boat and Ships by Cyrus Hamlin, N.A.) where the author describes cutting up a cucumber, pickle or zucchini cut in order to understand vessel geometry. I have not figured that out yet. If you have done that, it would be interesting to me.
So when did the professor tie the object lesson into an anti-American, socialistic rant? Kidding.
As a music major, my lone science class was geology. Turned out to really well-taught and very interesting.
I have a mechanical engineering handbook open on my desk at this moment because I, an electrical engineer, need to finish some spot-checking of some structural steel estimates. Needless to say, I have an overly-generous margin in there. If I win this work, I’ll pay a structural guy to optimize it for me.
As I recall he was a Korean War vet. Yes. It was that long ago.
I thought you were going to end up telling us that Jones and Smith got married and lived happily ever after.
If my materials engineering class had been this interesting, I’m sure I would have enjoyed it much more. All I really remember is getting to play with hydraulic presses to measure stress and strain for different materials, which is fun, but not nearly as enjoyable as a good teacher.
They may have for all I know. It was the only class I shared with either.
A great professor and a wonderful lesson that got the information to stay with you. The only thing I remember from my metallurgy class is my professor’s accent. I think she was from India and pronounced metallic as metal-leak. Which, because of the course, she got to say a lot.
Great story!
I remember in my first physics class in college, the professor wanted to give us a practical demonstration of torque and the conservation of angular momentum. He brought out this bicycle rim with a heavy chain wrapped around the outside, and handles extending from the axle on both sides. He then had a student sit on a stool that could rotate, holding the wheel vertically with both hands.
The prof spun the wheel as hard as he could, then told the student to rotate the spinning wheel until it was parallel to the floor. Amazingly (to us at the time), the student started spinning around on the stool. The prof asked him to reverse the position of the wheel. As the student changed the wheel’s position, his rotation came to a stop, then went in the other direction.
Needless to say, everyone wanted a turn on the stool, even staying after class to do it.
Sounds like a discussion of stations in boat design. Since I am a sailor, not an architect, I am interested in sections in racing sailboats. Once, when my younger son was about ten, I got a copy of the plans for our family sailboat. We built a balsa model of the boat by using the stations to make the balsa sections and then planking it with more balsa. My son will be 50 next year and still has those plans. I don’t know where the model is.
Great story. As others have said, he sounds like he was a great teacher. It’s well done that you can share it with us so many decades later.
This conversation is part of our Group Writing Series under March’s theme of Feats of Strength. If you have a tale of strength to tell, or even a tale of lack of strength, why not share it with us? We still have two openings in the future this month, and also two in the past if you happen to be used to having ridiculous deadlines put upon you. Why not head over to our schedule and sign-up sheet, which is waiting for you?
In high school physics, I was the demonstration dummy for the conservation of angular momentum. They put me on a stool in front of the class holding 10 kg masses (maybe 5 kg) in my outstretched arms. Then they spun the stool, and told me to pull my arms in towards my body.
I almost fell of the stool it accelerated so quickly.
It’s good they saw such potential in you so young.
It was the only thing I was good for in Physics class.
Good one!
I just thought of another neat demonstration. In grad school, I took a plasma physics class. The prof had a device that would crush cans using what’s known as the “theta pinch”. I couldn’t find a video of him and his device on line, but there several floating around. Here’s one:
https://www.youtube.com/watch?v=DocVqsdDQG8
Which reminds me – I read something a few years ago, and know it was true in my case. Curious if it’s more generally true.
The standard high school science curriculum progression is Biology, Chemistry, Physics.
The reason they’re taught in that order? Alphabetical. Way back when, “they” knew they had to teach them, and couldn’t figure out any better reason to order the classes a particular way.
On my first day of materials class there was a torch blowing a large flame against a tile when we walked into class. Basically one entire side of the tile was engulfed in flame. About 20 minutes into class, the professor turned off the flame and then immediately picked up the tile bare handed. Turned out it was a heat deflecting tile from the space shuttle.
In my high school, it was bugology, phyzooks, and then chemistry.
I think the order is that way because it goes from easiest to hardest. That was my experience. Besides, everyone had to take biology because (drum roll) it was the class sex ed was taught in!
We had health or physiology as the sex-ed choices. School districts were still independent when I went to school. The next district over or the district in the next state might have done it differently.
Done what differently?
Curriculum design. You, naughty, naughty boy!
I guess our school did it differently too. We didn’t have a separate health class, so they must have figured biology was the best place to teach it.
We moved between my Sophomore and Junior years in high school. The school I left had the progression Chemistry, Biology, Physics. The school I moved to had the same progression as above. The result was about 2 weeks before I was supposed to graduate, my counselor realized I hadn’t had biology and therefore by state law was not eligible to graduate. At this point I had already been accepted to engineering school. I went on to get my engineering degree, and an MBA. Not bad for someone who never finished high school.
My state only required two years’ of science classes to graduate when I was in high school. I had zero interest in anything but physics (my dad is a physicist), so I skipped biology and took an accelerated physics class at the local magnet school that gave me three credits of science. I still took chemistry my junior year and was constantly annoyed that chemists a) don’t realize that everything beyond the alchemy level (mix these two things together for a great surprise) is physics, and b) they use the wrong symbols for everything (h is Planck’s constant, dammit).
I still had to take bio in college, and hated it. :P
Professors were still doing that back in the ‘90s, when I was an undergrad.
Can you do that today?
In my high school physics class we had slinkies for demonstrating wave functions, and several of the guys got the bright idea to hook them all together to make a giant wave extending down one very long hallway outside the science classrooms. They let loose a giant wide nasty wave and lost control of it when it reflected off the far end. It certainly cleared out the hallway and ruined a lot of the slinkies. Our teacher, who was a spry 70 year old lady (her mother was still living at 103) was furious and lectured us for quite some time, calling us all poor white trash. I remember it as the highlight of physics class, though.