Course Introduction 3.20 Materials at Equilibrium, Fall 2003

Actually, the title is interesting. It is Materials of Equilibrium. A lot of people who look at the content would think of this as, you know, this comes out of a course that used to be called Thermodynamics of Materials which is a standard staple of students who would do graduate materials education. Almost everybody would have this as a requirement. We deliberately changed the title to Materials of Equilibrium to make it something broader. We really wanted it to be Standard Classical Thermodynamics, which is what we do, but wanted to broaden that into sort of modern metrics to understand and study the energetics of the materials. What we do is we essentially teach, first of all, we teach three large segments. One is classical thermodynamics. And the idea is that people need to see the general frame in which you can set up an energy description for materials. How they react with their environment. How they react with other systems. So we wanted to teach them first the general framework in which to study energetics of materials. And the reason we want it that general is because thermodynamics really has evolved from being a science with a fixed application in material science that would have been used for studying metallurgy. You know, making steel, refining of ores and things like that. Very standard sort of application so that you could almost teach through the applications. Now thermodynamics has much more evolved to a much broader range of applications and materials. People use it on polymers. People use it on thin films. People use it in biology. So we couldn't just teach through applications anymore because there were too many. And we don't know where it might go next. So, because of that, I feel it real important to teach the generic framework so that a student can go with this and whatever they meet in their research apply it. So that is about six weeks of lecturing. After that, since thermodynamics is a macroscopic description of materials, I would teach statistical mechanics, which is the science that teaches you how to relate microscopic details, atomic level details to the thermodynamics. [UNINTELLIGIBLE PHRASE] titanium and another aluminum. So that is the second piece. And then the third piece is essentially taking all that and making it more applied. So now we say we are going to study solutions of materials. We are going to study thin films of materials. We may study now polymer mixtures. So those are the essential three pieces. And so there is an enormous emphasis on understanding the concepts behind what we teach. Because of that, for example, I do not assign homeworks on a weekly basis. I feel that the time over which things have to sink in is longer than a week in many cases. So we have sets of assignments that go on the Web. Students do not have to turn them in. A week later the solution is gone so they can work on this at their own pace. Well, the way we evaluate the students is in a very classical sense. We have two mid-term exams. The first one is purely on classical thermodynamics so it would be the first block of the lecture, the course. And there is a second mid-term which largely covers statistical mechanics and some classical thermodynamics. And then there is a comprehensive file. And, actually, the comprehensive file is weighted for half of the grade, so it is a very extensive weighting. And, again, that comes back to the idea that I feel, you know, this is a difficult subject, thermodynamics, and students need sufficient dwell time on it. So I feel that I can only really evaluate them in the end whether they understand it. If it were up to me, I would probably put even more emphasis on the final. And so, the final is comprehensive. It covers the whole course, and also the integration between the different sections. So 3.20 Energetics of Materials is a required course for all our incoming DMSE students. So they would take it typically in their first semester at MIT. It is a recommended course for master students. Masters can also take a shortened version of it. But typically what we see is that most of the students in Material Science will take that course in their first semester. And the reason it is taken in the first semester is there are a lot of other classes that build on it. You could see this course really as the kind of basic description of how materials evolve, what their equilibrium states are, how they interact with their environment so other classes that talk about phase transformations between materials or mechanical behavior, the relation between mechanical properties and processing would all build on this course. It makes sense that it is taught early. So the course has a thermal help email list which gets logged now. That started, we always had a thermal help email, and those emails would get distributed to the staff in the class. And whoever felt they could answer the question would pick it up and cc everybody so we knew it was answered. And then we had a creative TA who said, you know, we have all these really interesting answers to questions and we really should aggregate this. And so, that is how the log got started. And now you can actually look online and look at the questions that were asked other years, the answers that were given. And the students find that very useful. Thermodynamics is a difficult subject. It is one that is extremely difficult to learn in one setting, you know, and in one pass through the material. You know, it is not like taking a course in PowerPoint or something where you learn facts. Thermodynamics is more about assembling the facts in a continuous framework. And it took me many years to do that. So maybe my advice is to not give up. It is a tough subject, but it is one of these subjects that once you get it you wonder why it was so hard.