In recent years, composite material (this word uses Composite Material) more. So what is composite material? Simple for, composite material is by two plant or a variety of differring the material that material is combined and becomes. A kind of among them material serves as matrix, the material of other serves as add wild phase, matrix is successive normally, adding wild phase can be grain, fiber, layer board. Can thinking to add wild phase is to enchase in matrix. The material of a kind of any the property of material of complex of this kind of group and its composition differs significantly.
All sorts of material in composite material learn from others's strong points to offset his weakness each other on function, generation synergism, make integral performance excel constitutes material formerly and satisfy all sorts of different requirements of composite material. Composite material relatively before material can have a lot of advantages: The sex of exhaustion of weight comparing, Gao Kang and corrosion resistance, be able to bear or enduring that increase chafes and wear-resisting caustic sex, low coefficient of thermal conductivity mixes high intensity attribute of small hot coefficient of expansion, material has adjustability to ask in order to satisfy a design. For example material of pottery and porcelain has high temperature resistant advantage, but it is more fragile, to enhance its tenacity, the fiber that uses high strenth, tall flexibility and pottery and porcelain base compound hind, this kind of composite material can use as undercarriage of undercarriage of Buddhist templeput on the brakes of nose awl of cover of antenna of spray pipe of liquid rocket motor, missile, space shuttle, aircraft and high-grade car Buddhist templeput on the brakes, become a of hi-tech new material main branch.
The history that composite material uses is OK restrospect to ancient time. From ancient up to now the straw of continue to use enhances clay, with lime foam wall among them mix into enters hemp and hair in case craze, already used ferroconcrete of about a hundred years, the layer plywood of production furniture, add the balata tire that has line of high strenth fiber. They are by two plant or the material of two kinds of above is complex and into. The composite material that we say now is not to point to these of course, show 20 centuries develop the new composite material that rise after 40 time however, call advanced composite material sometimes.
20 centuries 40 time, because of the need of aviation industry, developed fibre glass to enhance composite material (common weighs glass reinforced plastics) , appeared from now on composite material this one name. What 50 time need special specification with be in composite material treatment is, composite material treatment often is one-time make structural finished product. Before material production and structure are built undertake apart, and composite material project is more compound two measure one condition. The graph shows car case 5 times is made by composite material, two people can be raised come, it is thus clear that it is very light, it is one-time make by the composite material that make. The plane airframe of below also is one-time make. Hind, developed the high strenth such as fiber of carbon fiber, black lead and boracic fiber and fiber of high standard quantity in succession. 70 time appeared fiber of fragrant black silk ribbon and carborundum fiber. These high strenth, high standard measures fiber, can wait for metalloid matrix with synthetic resin, carbon, black lead, pottery and porcelain, balata or the metallic matrix such as aluminous, magnesian, titanium is compound, make the composite material that provides distinguishing feature each.
In this kind new composite material appears previously. The structural data that human place uses, have 3 kinds as follows:
01 metals stuffSteely, aluminium and aluminium alloy, copper, magnesian, titanium; 02 inorganic metalloid materialBrick, made of baked clay, glass, pottery and porcelain, cement, black lead, carbon; Material of 03 high polymerBalata, colophony, plastic, fiber, adhesive, coating. The composite material of —— of the 4th kind of material that appears now, it is above 3 kinds of material are complex and become material. 3 kinds of material can regard above as the matrix of composite material, also can serve as in enhancing addition to enter matrix.
About composite material, the most important, the problem that has side of the following tripartite needs to consider.
Above all, it is the composition of composite material, construction and treatment problem. What is chosen matrix, adding wild phase is join matrix with what means and the distributinging that enhances photograph oneself and weave way, how be machined and realize this kind of composite material.
Of composite material making a structure is varied, be like next face graphic representation. Have those who enhance body random to disperse, have thread one-way increase, those who have the formal overlay with layer plywood, have interlining structure, have three-dimensional braid etc, by no means an isolated case, and the tectonic form that still can study development is new.
What need special specification in composite material treatment is, composite material treatment often is one-time make structural finished product. Before material production and structure are built undertake apart, and composite material project is more compound two measure one condition. The graph shows car case 5 times is made by composite material, two people can be raised come, it is thus clear that it is very light, it is one-time make by the composite material that make. The plane airframe of below also is one-time make. Graph the car case that 5 composite material make and airframe next, it is the design problem of composite material. By the tectonic form of the mechanical nature of composite material constituent and composite material, how to calculate the full physical power that gives composite material learns property and carrying capacity, this is the crucial question with mechanical composite material. In other words, have this thing only can free, design outstanding composite material ability to reach free level quite. As a result of the diversity of composite material and complexity, have all a kind of method is right according with very hard so material is effective, often be to be aimed at different composite material to construction studies and develop necessary design and computational method. For example the method of composite material calculation of layer plywood, fiber enhances the computational method of composite material to wait a moment. The document of this respect and book already special much, when encountering this kind of problem need consults concerned document. When structure of specific computation composite material, can choose to have representative small unit above all, all sorts of parameter that the stress meet an emergency after obtaining this unit smooth leveling through computation concerns, be in next those who get is small the relation issues yuan of stress meet an emergency after be being changed on average, the whole of structure of computational composite material is answered. Finally, make the same score the stress of leveling and meet an emergency according to what get again, in every small yuan on the stress meet an emergency of each constituent mixes computational composite material the stress on the interface distributings. Finally, make the judgement of structural intensity. As a result of the complexity of composite material, place combines the computation of material and design about Yu Fu, need have the aid of undertakes at the computer. Existing not little solid body is fortunately mechanical, the consideration that includes to be aimed at composite material is mechanical business can be used with software. Nevertheless, mechanical to composite material research still needs to throw huge manpower material resources. Finally, it is the between each constituent interface problem in composite material. Since composite material is by two plant or the material of two kinds of above is complex and become, the interface with so direct constituent appears particularly important. If agglutinate is incompact between the interface, there is collaboration between constituent so, each are each, the advantage that can not see a variety of material close instead function can be reduced. But interfacial union is not simple question, study behaviour of composite material interface, can say the crucial question that is mechanism of research composite material. Say commonly, the interface between two kinds of material is not a piece of ideal curved surface, what two kinds of stuff that have certain ply however exist interactively is stereo. Amid can produce all sorts of change. Main is to cause each infiltrate each other between constituent, diffuse, the physics that freedom of interfacial look look, interface can penetrate each other changes; Bring about the chemistry on the interface to react, produce new material to form the chemical change of new bound facing; The stress on the interface distributings. Because there are a lot of this complex things on the interface, want to undertake handling to the interface first before undertaking composite material is machined sometimes so. Care an interface very much from mechanical angle stick receive prison degree, and the question that the interface leaves craze in what condition, interfacial craze problem has made calculation mechanical with composite material mechanical a kind very the task that gets attention. Composite material is arisen although have half many century only, but the success that has gained your person to fix eyes upon, he is changing the face of a lot of hi-tech structures. Accordingly, it is one of hi-tech domains of intense competition on international. Who is planted in this hi-tech domain is one-up, precede on aviation, spaceflight, national defence with respect to the likelihood. Capable mechanical home people, show hand of one private parts in composite material!