Functional materials refer to biological characteristics with special electrical, magnetic, optical, thermal, acoustic, mechanical and chemical properties and their mutual transformation functions. They are not used for structural purposes, but high-tech materials that realize the main purpose of feeling, measuring, displaying, controlling and converting information and energy. Functional materials are the forerunner and foundation of modern high-tech development, and they are new materials that have been developed and applied in 2 1 century. Its application in automobiles is also obvious.
Key words: fast heat dissipation, high temperature resistance and long life.
Abstract: Functional materials refer to advanced materials with special functions of mutual conversion between electricity, magnetism, light, heat, sound, power, chemical weapons and biological weapons. They are not used for structural purposes, but for energy information and feeling, or for measuring, displaying, controlling and transforming space. Functional materials are the basis of modern high-tech development and pilot test, with emphasis on the development and application of 2 1 new materials. Its application in automobiles is obvious.
Key words: fast heat release, high temperature resistance and long life
Before I took the course of mechanical engineering materials, I always thought that this material was nothing more than steel or iron. I have always thought that this course is not very interesting with the original retarded idea, but this idea can be said to be completely changed after class. In fact, it is too light to say "change", but rather "awakening". Why do you say that? Think about it for so many years, I always thought I had a little knowledge of cars, which is why I applied for this major, but in the end, I didn't even know the difference between steel and iron. What a pity! Is this just a "change" in concept? The answer is definitely no, the change of ideas is only a superficial phenomenon, but what people really get is a lesson, a lesson of self-knowledge and what to learn. This is the ultimate goal of this lesson. So I call this feeling "awakening". These are just students' feelings about the course.
Speaking of the classification of this material, the classification of engineering materials is varied, which makes me feel very troublesome. Don't know how to reason. Thinking of this, I think of an analogy you made: the material on the earth is like the people on the earth, with billions of people. There must be thousands of such materials. How to distinguish certain characteristics of materials is just like distinguishing who can have children on earth. As long as we master its laws, the problem will naturally be much easier to solve. Maybe this analogy will only be laughed off as a joke for some people, but I think this is the uniqueness of the professor. Humor cells are not available to everyone, but combining humor with theory is more valuable and can better reflect a person's profound knowledge. There is also the importance of this course to the future work of mechanical students like me. Based on the above points, we should learn this course well.
Engineering materials refer to engineering-related materials (structures, parts, tools, etc.). ) In the field of solid materials, it is mainly used in machinery manufacturing, aerospace, chemical industry, construction and transportation. There are many kinds of engineering materials according to different classification methods. According to its application fields, it can be divided into mechanical engineering materials, building engineering materials, electronic engineering materials, aviation materials and so on. According to its performance characteristics, it can be divided into structural materials and functional materials: structural materials are mainly mechanical properties and have certain physical and chemical properties; Functional materials are materials with special physical and chemical properties, such as electricity, magnetism, light, heat, sound, biology and other functions and effects and their conversion characteristics. Structural materials are widely used and are the main materials in contemporary society; Although the amount of functional materials is small, it is the key to high technology, and it is a new material with intensive knowledge and technology and high added value. Due to the limitation of the title of the paper, I won't talk about other materials here, only functional materials, which are said to be "powerful".
In fact, the development history of functional materials is as long as structural materials, but compared with structural materials, their dosage is not comparable to some extent, but their importance has not been ignored. With the development of power technology, electrical functional materials and magnetic functional materials have made great progress. In 1950s, with the development of microelectronics technology, semiconductor electronic functional materials developed rapidly. In the 1960s, laser technology appeared, and in the 1970s, photoelectric technology also developed corresponding functional materials. After 1980s, new energy functional materials and biomedical functional materials rose rapidly. With the development of science and technology, there are more and more varieties of functional materials, and their application scope is wider and wider, and their position in the national economy will rise sharply. From the above development and progress, it is not difficult to see that functional materials are receiving more and more attention. This concern is not only determined by technology, but also prompted by various problems. This is the so-called no problem. Look at the wide application fields of the above functional materials, and then look at the knowledge covered by these different materials in this book. As a student who studies mechanical manufacturing instead of materials science, it is more difficult than going to heaven, at least it is a problem. Writing here, I thought of what the professor said, that is the relationship between "watermelon" and "sesame". I think this sentence is too reasonable. "Watermelon" and "sesame" should be understood, but when it comes to specifics, what is our focus? In fact, it is obvious that "watermelon" is our focus. What does the so-called watermelon here mean to us? And what is sesame? So the question before us now is how to distinguish this "watermelon" from "sesame". Perhaps this question is taught so that we don't have to delve into some internal details of the material when studying this course. After all, we are not students majoring in materials. What's more, we are an application-oriented university, and we will go to work mainly for applications in the future. There is no need to study too deeply and carefully. Although you don't need to master it skillfully, you can't get the necessary understanding. This is the professor's definition of watermelon and sesame. Now I classify these watermelons and sesame seeds as functional materials. Faced with a variety of functional materials, I think the material that is close to my major should be "watermelon", and those that are not closely related at least now should belong to that "sesame". So for me, a student majoring in automobile, it must be the "watermelon" building that is related to automobiles.
Speaking of cars, let's talk about the improvement and application of some functional materials in cars. When it comes to cars, you can't help but mention this wheel. I have a hobby since I was a child, and I have a soft spot for wheels. I think the first impression of a car actually plays a great role. In fact, the composition of wheels is very simple, tires and rims. Anyway, although the rim was used as a mechanical material to support the car from the beginning, I personally think it should be a functional material now. Why do you say that? With the development of today's automobile industry, the speed and acceleration of the automobile are constantly improving, and people's requirements for automobile comfort are also improving, so this wheel is no longer just a mechanical role. From the daily use process, some big or small problems are exposed. So "aluminum alloy rim" was born, and its performance was better than that of "steel rim". Because the thermal conductivity of aluminum alloy is three times that of steel, the heat dissipation effect is good. After long-distance and high-speed driving, the tire can maintain a proper temperature, which makes the tire difficult to age, prolongs its service life and reduces the chance of puncture. Moreover, the aluminum alloy rim has good roundness and good balance during operation, which eliminates the general body bump and steering wheel jitter. What's more, I think aluminum alloy rims are corrosion-resistant and have many design styles. Based on the above points, I personally think that the application of "aluminum alloy rim" should be as a functional material (personal opinion). Attached below is a set of physical drawings of "aluminum alloy rim" and "steel rim"
After lifting the wheel, lift the brake. When it comes to braking, you will think of a word "thermal recession" that you often hear in your ear. I guess you're not too familiar with this. It's actually quite simple. The phenomenon that the braking capacity of the whole braking device decreases due to the heat generated by the friction between the brake pad and the brake disc during automobile braking, and the main reason for this phenomenon is determined by the heat resistance and heat dissipation of the material. Although opening a lot of holes in the brake disc can increase some heat dissipation area to a certain extent, it can only cure the symptoms. The real solution should be the material itself, that is, to find a material whose performance will not decrease at high temperature. Looking around, ceramic material seems to be an ideal target, but it is restricted by other characteristics of ceramic material, which leads to its not widely used in engineering. However, this application has indeed been applied to the manufacture of automobile brake discs. However, due to the limitation of production technology and cost, this technology is only applied to some high-end sports cars or sports cars with high braking requirements. I have little knowledge. As far as I know, the car with ceramic brake discs seems to have only "Porsche" in my impression. Someone will definitely ask me why I remember "Porsche". It's actually a coincidence. I usually don't care about the material when I read books about cars, but it is this ceramic brake that keeps me fresh in my memory. Why? That's because it surprised me so much. Guess how much it costs for Porsche to choose a set of ceramic brake discs? As a car fan, I thought it was just a set of brakes after a little guess. Thousands of people died, but when I saw the price list, I almost didn't vomit blood. Because it took a long time, if I remember correctly, it was probably less than 1 10,000 euros, which is nearly110,000 RMB. At that time, I felt a little incredible, but after learning this course, I was a little puzzled and figured out why this brake is also optional. Although this technology has not been popularized yet, with the development of science and technology, Pu Sang has used ceramic brakes.
When it comes to cars, we can't help but talk about the eyes of cars-headlights. In fact, this lamp was built for lighting from the beginning, and it is still built now.
It still only has this function, but now the lamp is brighter, more beautiful and has a longer life. To achieve all this, technology is essential, but the key is to look at the materials. From tungsten wire heating to halogen lamp and xenon lamp, the difference between the two lamps can be clearly seen from the above set of pictures (the previous headlight is on the left and the xenon headlight is on the right). As for some professional color temperatures. So from the above, we can see the importance and broad development space of functional materials.
In fact, the application of functional materials in automobiles can be said to be many. However, due to the shackles of professional knowledge and the strangeness of material knowledge, it is beyond the ability to further write, so students here can only "put down their keyboards and learn on the spot". I hope the professor will give me more advice!