home

Composite materials. Properties of composite materials

High corrosion resistance, impact load capacity, excellent surface quality, beautiful appearance have led to wide application composite materials in almost all industries.

These materials occupy a prominent place in the production of products. for road and urban transport. Cases are made from them. cars, buses, details interior design, truck cabins, fuel tanks, tanks for transportation of liquid and bulk cargoes, hulls and parts of the interior of trams and buses.

Composite materials are widely used in aviation and rocket and space technology where their properties such as high specific strength and resistance to impact are used high temperatures, resistance to vibration loads, small specific gravity. These materials are used to manufacture body parts and interior details.

Composite materials are widely used in the field shipbuilding. The unique properties of composite materials make it possible to manufacture high-strength, lightweight hulls for boats, yachts, and boats.
Composite materials are also used to make lifeboats for oil tankers. Such boats are able to carry the crew of the ship out of the area of spilled burning oil in the event of an accident. This possibility was achieved due to the unique properties of the materials used, their high thermal insulation and fire resistance.

The development of the composites industry in the Persian Gulf is extremely fast. Composite materials were used in one of the most prestigious projects in the region - construction of Jumeirah Reach Tower Hotel. The Jumeirah Reach Tower hotel, already completed in Dubai, is announced to be the most tall building hotels in the world. Its height is 321 meters, which is higher than the Eiffel Tower in Paris. Approximately 33,000 square meters sandwich panels connect the hotel rooms and the gigantic, almost 200 meters high atrium. The panels are made from composite materials. The fire retardant resin and gelcoat were engineered and fully tested for use in this project. The recommendation and experience of this project is expected to generate considerable interest in the construction industry.

In the region of railway transport Composite materials are gradually taking the lead due to their excellent properties. Every year everything more companies they are switching to the manufacture of composite materials not only of individual parts, but also of bodies as a whole.

A real revolution was made by composite materials in the field of Agriculture. The anti-corrosion properties of these materials allow them to be used where other materials cannot withstand. These are elements of livestock farms, storage tanks mineral fertilizers, waste, agricultural preparations. Composite materials are used for the manufacture of bodies of agricultural machinery. This allows you to significantly save money not only during production, but also during operation, since during the off-season of the tractor, harvesters do not require maintenance costs for body parts, and the service life of these parts is much longer.

One of the ever-expanding areas of application of composite materials is bridge building. The use of fiberglass opens up a promising way to build bridges from new materials. The construction under consideration is a 40 meter long bridge stretched across one of the busiest railways in Denmark. The first composite bridge specially designed for the creation of railway crossings was made. A key condition for the creation of the bridge, for one of Denmark's busiest railways, was that it had to be installed as soon as possible. At the same time, the building had to meet certain practical and aesthetic criteria. The bridge was assembled in 16 hours. The work was done at night. The bridge consisted of three components that were mounted on bolted supports - by the way, the only elements of the bridge that required connections.

Composite materials will be used more and more as a material in ground construction. The benefits are numerous: composite bridges that require only cosmetic maintenance for more than 50 years to come. A similar bridge built of steel would weigh 28 tons and would need to be replaced every 25 years. The same applies to reinforced concrete bridge, which would weigh 90 tons. One of the main advantages of lightweight composite structures is that they require smaller, less expensive supports. In addition, they are not subject to corrosion. The bridge is designed from standard profiles and can be produced at a lower cost than a comparable steel or concrete bridge.

A new complex bridge was built in the Swiss Alps last fall. This bridge consists of two elements weighing 900 kg each, which were installed using a helicopter. The elements were glued and bolted together. The bridge, assembled from steel, could hardly be transported by helicopter. Another advantage of the project is that the bridge can be easily dismantled in case of spring floods.

IN defense industry composite materials played important role in strategy and direction latest developments. So protective helmets, body armor, traditionally made in all countries for many years from metal, are now also made from composite materials. high speed ships, transport ships, stealth aircraft, all this was created only through the use of composite materials, the constant search for new materials and technologies.

Composite materials are widely used in oil refining industry. Currently, elements of oil platforms, pipes for oil and gas pipelines are made from these materials. This year, the construction of a plant in Uzbekistan for the production of pipes for oil and gas pipelines is being completed. The capacity of the enterprise is determined based on the volume of consumption of only fire-resistant unsaturated polyester in the amount of 6.5 thousand tons per year.

Blades and bodies wind farms, trailers, refrigerators, household items, sanitary ware, artificial marble, polymer concrete, waterproofing of subway tunnels, insulating pads, seats for transport and public places, small architectural forms, furniture, all this and many more are currently produced fromcomposite materials.

During this method, pre-prepared fillers are used. Thanks to this method, a high uniformity of products for strength is guaranteed, and indicators are controlled. However, the quality of the resulting product depends to a high degree on the skill and experience of the workers.

The production of fiberglass products by hand molding is divided into several stages. The first stage is called preparatory, during which the surface of the matrix of the expected product is cleaned, then it is degreased and at the end a layer of separating wax is applied. At the end of the first stage, the matrix is covered with a protective and decorative layer - gelcoat. Thanks to this layer, the outer surface of the future product is formed, the color is set and protection is provided from harmful factors such as water, ultraviolet and chemical reagents. Basically, negative matrices are used to produce the finished product. After the special layer of gelcoat dries, you can proceed to the next step, which is called shaping. During this stage, the initially cut glass material is placed in the matrix; another type of filler can also be used. Next comes the process of forming the "skeleton" of the expected product. Then the resin with the catalyst, pre-mixed, is applied to the prepared glass material. The resin must be evenly distributed using brushes and soft rollers over the matrix. The last stage can be called rolling. It is used to remove air bubbles from the not yet cured laminate. If they are not removed, this will affect the quality of the finished product, so the laminate must be rolled with a hard roller. When the finished product has solidified, it is taken out of the mold and machined, which includes drilling holes, trimming excess fiberglass along the edges, etc.

The advantages of this method:

exists real opportunity get a product of complex shape and considerable size with minimal investment;
the design of the product can be easily changed, since embedded parts and fittings are introduced into the product, and the cost of equipment and the required equipment is quite low;
to make a matrix, any material is used that is able to maintain its proportions and shape.

The disadvantages of this method:

significant costs manual labor;
performance is quite low;
the quality of the product will depend on the qualifications of the molder;
This method is suitable for the production of small-scale products.

2. Spraying.

For small and medium-sized production, this method is suitable. The sputtering method has many advantages over contact molding, even though there are certain costs associated with the purchase of equipment for this method.

A special installation allows you to apply a protective coating and plastic. Due to this, preliminary cutting of the material and the preparation of a binder are not required, as a result of which the part of manual labor is drastically reduced. Special installations automatically make a hard count of the doses of resin and hardener, they also cut the roving into pieces required dimensions(0.8 - 5 cm). After the cutting process, parts of the thread must fall into the binder jet and soak during transfer to the matrix. Due to manual labor, the sealing process for fiberglass in the matrix is carried out using a rolling roller.

A number of advantages in the production of fiberglass by spraying:

there is a saving of time and usable space due to the fact that it is not necessary to cut the material and prepare the binder;
it is possible to reduce the number of production areas by reducing the number of specially prepared places for molding;
the speed of molding the product increases;
product quality control is simplified;
fund wages saves a lot;
due to the fact that roving is relatively inexpensive material, the cost of the resulting product is significantly reduced.

When the binder is prepared in a small amount, then with manual molding, up to 5% of the binder remains on the tools and container walls, which is rather uneconomical. It is known that the quality of the resulting product will depend on the skill and experience of the plant operator. This method uses the same tooling as during hand molding.

3. Pultrusion.

The technology of pultrusion is based on the continuous production of profile products from uniaxially oriented fibrous plastics. Profile product with a constant cross-section made of suitable material just and can be obtained by pultrusion.

Thanks to a special pultrusion machine, a fiberglass profile is produced. Such a machine consists of a section for the supply of reinforcing materials, a die, an impregnation section, a pulling unit, a control unit heating elements and from the cutting section. The oriented fiber package is best strengthened when dry and impregnated with the polymer composition pumped through the dry package. Thanks to this technology, air will not enter the material. Excess resin will flow back into the sump and be recycled. Roving, which is used as a reinforcing material, is wound from bobbins in a dry state and assembled into a bundle in a special way. Then the material enters the impregnation device - this is a special resin bath, where it is completely wetted with a polyester, epoxy or other binder. Then the already impregnated material is sent to a heated die, the task of which is to form a profile configuration. Then the composition hardens at the specified temperature. As a result, a fiberglass profile was obtained, the configuration of which repeats the shape of the spinneret.

It has been proven that products obtained by pultrusion are superior in properties to parts made by classical molding methods. The increase in the cost of this method is due to a number of advantages that are characteristic of this process. Benefits include tighter control of tension and fiber directionality, reduced pore count, and retention of fiber content in the composite. Obviously, even the interlayer shear property is unambiguously improved. On the this moment several variants of the main pultrusion process have been developed, which are of interest to many and mean a lot to the industry. Their advantages are good electrical, physical, chemical and thermal properties, high performance and excellent dimensional tolerance. For the manufacture of permanent lamellar and sheet semi-finished products, one of such pultrusion methods is intended.

However, each method has its drawbacks. This method is characterized by such a disadvantage as the speed of the process, which will depend on the temperature and the rate of solidification of the binder. Usually it is small for low heat resistant polyester resins. Another disadvantage is that it is difficult to provide a constant section of the product along the length, except for products with not very complex shape sections - square, round, I-beam and others. To get the product, you need to use only threads or bundles. However, for Lately these shortcomings of the method for obtaining profiled products were gradually eliminated and the application of this process was noticeably expanded. Composition based on polyvinyl ethers and epoxy resins are used as polymer matrices. The use of such polymer matrices based on polysulfone, polyethersulfone and plasticized polyimide makes it possible to achieve a speed of forming rods with a diameter of about five mm at a speed of about one hundred and two m/min.

To obtain complex reinforced profile products, it is necessary to use the method of drawing layered materials, which consist of fibrous mats or fabrics. To date, methods have been developed for producing tubular products that combine the winding of a spiral layer and broach. blades wind turbines that have a complex profile cross section, can be cited as an example of the use of materials having complex scheme reinforcement. Tooling has already been developed for molding semi-finished products for automotive leaf springs, which have a curved surface and a non-constant cross section.

4. Winding.

One of the most promising methods for molding fiberglass products is the fiber winding method, due to the fact that it creates the required structure of the filler in the finished products, depending on their shape and operation features. Thanks to the use of bundles, tapes, threads as fillers, it allows to ensure maximum strength of products. Moreover, such fillers are the cheapest.

The fiber winding process can be described as a relatively simple method in which a reinforcing material in the form of a permanent roving (tow) or thread (yarn) is wound around a rotating mandrel. Special mechanisms monitor the winding angle and the location of the reinforcing material. These devices move at a speed that matches the rotation of the mandrel. The material is wrapped around the mandrel in the form of strips that are in contact with each other, or according to some special pattern until the mandrel surface is completely covered. Layers one after the other, can be applied at the same angle or under different angles winding until the required thickness is reached. The winding angle varies from very small, which is called longitudinal, to large, circular. This arrangement implies 90 0 relative to the axis of the mandrel, capturing all the angles of the helix of this interval.

The thermosetting resin serves as a binder for the reinforcing material. In the wet winding process, the resin is applied directly during the winding process. The dry winding process is based on the use of roving, which is pre-impregnated with resin in the B-stage. Hardening is carried out at increased temperature without excessive pressure. The final stage of the process is based on taking the product from the mandrel. If necessary, finishing operations can be carried out: mechanical processing or grinding method. The main winding process is characterized by many variations, which differ only in the nature of winding, as well as design features, material combinations and equipment types. The structure must be wound as on a surface of revolution. However, it is also possible to form other types of products, for example, by compressing a still uncured wound part inside a closed mold.

The design turns out to be similar to a smooth cylinder, pipe or tubing, the diameter of which is obtained from several centimeters to several tens of centimeters. Winding allows you to mold products of conical, spherical and geodesic shape. To get vessels high pressure and storage tanks, an end cap must be inserted into the winding. It is possible to form products that will work under non-standard loading conditions, such as external or internal pressure, compressive loads or torque. Thermoplastic pipes and vessels made of high-pressure metal are strengthened by external bandages during winding. The resulting products are characterized by a high degree of accuracy. However, there is another side to the winding process, which is characterized by slower production speeds. The advantage is that absolutely any permanently reinforcing material will fit for winding.

Various types of machines can be used for the winding process, from various lathes and chain driven machines to more complex computerized units characterized by three or four axes of movement. There are also machines that continuously produce pipes. For the convenience of winding large tanks, portable equipment must be designed at the installation site.

The main advantages of the winding method:

economically profitable method of laying material due to the speed of the process;
the ability to adjust the ratio of resin / glass;
low own weight, but at the same time high strength;
this method is not disposed to corrosion and decay;
relatively inexpensive materials;
good structure of laminates, due to the fact that the profiles have directional fibers, and good content glass materials.

5. Pressing.

The pressing process consists in directly giving the desired shape to the product under the influence of high pressure, which is formed in the mold at a temperature of rapid solidification of the material. Due to the external pressure in the material being pressed, its compaction and partial destructurization of the former structure occur. The friction between the contacting material particles, which is formed during compaction, causes the appearance of thermal energy, which will definitely lead to the melting of the binder. After the material passes into the viscoplastic state, it spreads in the mold under the action of pressure, forming an integral and compacted structure. The hardening process is based on the cross-linking reaction of macromolecules due to polycondensation between the free groups of the binder. The reaction requires heat, during which low-molecular, volatile substances are released, such as methanol, water, formaldehyde, ammonia, etc.

Parameters for direct pressing technology:

preheating temperature;
pressing pressure;
pressing temperature;
temporary exposure under pressure;
prepress parameters;

The pressure acts directly on the material in the mold cavity during direct pressing, so mold parts may wear prematurely. Depending on the dimensions of the product, the pressing cycle can be from 4 to 7 minutes. Direct compression of plastics for reinforcement has two varieties, which depend on how the fibrous filler is impregnated:

Dry, pre-impregnated canvases and fabrics are pressed;
Pressed with impregnation in the form.

The first method is more popular. Direct pressing is used to make products with a relatively simple shape. Due to the high demands placed on the quality of the outer surface of the part, automatic installations were created for dosing components in the preparation of blanks from prepregs. Special automatic manipulators have been designed, which load packages of blanks into multi-cavity press molds. A generation of new high precision presses are equipped with modern systems control, thanks to which it is possible to obtain parts with a high-quality surface, and their cost is approximately the same as steel parts.

6. SMC technology.

A major barrier to the spread of composite materials is poor fit. traditional technologies their release to the needs of modern large-scale production, moreover, fully automated. To date, composite parts still remain "piece goods". Expensive labor of experienced personnel contributes a high share of the cost of these materials. Despite this, for last years we have made significant progress in the preparation of automatic methods for the production of composites. SMC technology has become one of the most sought-after developments.

The end products of this technology are subject to a two-stage process. The first stage of the technology is characterized by the fact that the prepreg is produced on an automatic conveyor plant, and already at the second stage, the prepreg is processed in steel molds into finished parts. Let's describe these stages in more detail. Unsaturated polyester resin used as the basis for the binder. Its merits include low price and short curing time. The reinforcing component is chopped fiberglass, which is randomly distributed in the volume of the sheet. Long-term storage of several months at room temperature is ensured by the resin curing system. Chemical thickeners increase the viscosity of the binder after the fiberglass has been impregnated by several orders of magnitude, thereby improving the workability of the prepreg, as well as increasing its shelf life. Mineral fillers, which are introduced into the binder in large quantities, increase the fire resistance finished products and, and the quality of their surface is noticeably improved.

The resulting prepreg is processed in an automatic process by pressing in heated steel molds. These molds are similar in design to injection molds for thermoplastics. Thanks to the binder formulation, the prepreg hardens at a temperature of 150°C and a pressure of 50-80 bar at a rate of ~30 sec/mm of thickness. Very low set shrinkage is an important feature of the SMC technology. Due to the high content of mineral filler and special thermoplastic additives, shrinkage of up to 0.05% is obtained. The resulting products impact strength is 50-100 kJ/m 2 and destructive bending strength - 120-180 MPa. It is economically expedient to use SMC technology when producing high-quality composite products in large quantities from several thousand to hundreds of thousands per month. The European market produces hundreds of thousands of similar materials a year. The electric power, automobile and railway industries are the largest consumers of these materials.

7. RTM method (Resin Transfer Molding).

The RTM method is based on impregnating and molding composites under pressure, during which the binder is transferred into a closed matrix, which already contains fillers or preforms. Various fabrics a variety of weaves can act as a reinforcing material, for example, multiaxial or emulsion material, and powdered glass mats. The binder is resin, which gels for 50-120 minutes, having a low dynamic viscosity. GOST 28593-90 defines the viscosity and gelation time of the resin.

This method is perfect for standard volumes of 500-10,000 items per year. The design of the matrix consists of composite or steel forms that repeat the outer contours of the part on both sides. The structures have high temperature ratings that are held by the precise alignment of closed steel frames that are supported at the clamping points.

This method is ideal for the production of matrices from 0.2m2 up to 100m2. The design of the matrix consists of composite or steel molds. The contour matrix consists of a lighter and more flexible design. The halves of the matrix are interconnected under the influence of vacuum.

Advantages of RTM technology:

automated production, thereby reducing the random nature of human intervention;
there is a reduction and control of the amount of raw materials used;
the impact of the material on the environment is reduced;
improved working conditions;
relatively strong products are created due to better impregnation;
relatively cheap equipment.

composite material

Composite material (composite, KM) is an artificially created inhomogeneous solid material consisting of two or more components with a clear interface between them. In most composites (with the exception of layered ones), the components can be separated into a matrix and the reinforcing elements included in it. In composites for structural purposes, reinforcing elements usually provide the necessary mechanical characteristics material (strength, stiffness, etc.), and the matrix (or binder) provides joint work reinforcing elements and protecting them from mechanical damage and aggressive chemical environment.

The mechanical behavior of the composition is determined by the ratio of the properties of the reinforcing elements and the matrix, as well as the strength of the bond between them. The efficiency and performance of the material depends on right choice original components and the technology of their combination, designed to provide a strong connection between the components while maintaining their original characteristics.

As a result of combining the reinforcing elements and the matrix, a complex of composition properties is formed, which not only reflects the initial characteristics of its components, but also includes properties that isolated components do not possess. In particular, the presence of interfaces between the reinforcing elements and the matrix significantly increases the crack resistance of the material, and in compositions, unlike homogeneous metals, an increase in static strength does not lead to a decrease, but, as a rule, to an increase in fracture toughness characteristics.

To create a composition, a variety of reinforcing fillers and matrices are used. These are getinax and textolite (laminated plastics made of paper or fabric glued with thermosetting adhesive), glass and graphite plastics (fabric or wound fiber made of glass or graphite, impregnated epoxy adhesives), plywood ... There are materials in which a thin fiber of high-strength alloys is filled with aluminum mass. Bulat is one of the oldest composite materials. In it, the thinnest layers (sometimes threads) of high-carbon steel are "glued" with soft low-carbon iron.

Recently, materials scientists have been experimenting with the aim of creating more convenient in production, and hence more cheap materials. Self-growing crystalline structures glued into a single mass with polymer glue (cements with additives of water-soluble adhesives), thermoplastic compositions with short reinforcing fibers, etc. are studied.

Composites classification

Composites are usually classified according to the type of reinforcing filler:

fibrous (reinforcing component - fibrous structures);
layered;
filled plastics (reinforcing component - particles)
- bulk (homogeneous),
- skeletal (initial structures filled with a binder).

Advantages of composite materials

The main advantage of CM is that the material and structure are created simultaneously. The exception is prepregs, which are semi-finished products for the manufacture of structures. It should be noted right away that CMs are created for the performance of these tasks, therefore, they cannot contain all the possible advantages, but when designing a new composite, the engineer is free to set him characteristics that are significantly superior to the characteristics of traditional materials when fulfilling this goal in this mechanism, but inferior to them in any other aspects. This means that KM cannot be better. traditional material in everything, that is, for each product, the engineer conducts all necessary calculations and only then chooses the optimum between materials for production.

high specific strength (strength 3500 MPa)
high rigidity (modulus of elasticity 130…140 - 240 GPa)
high wear resistance
high fatigue strength
it is possible to make dimensionally stable structures from CM
ease

Moreover, different classes of composites may have one or more advantages. Some benefits cannot be achieved simultaneously.

Disadvantages of composite materials

Composite materials have enough a large number of shortcomings that hinder their spread.

High price

The high cost of CM is due to the high science intensity of production, the need to use special expensive equipment and raw materials, and therefore a developed industrial production and scientific base of the country.

Property anisotropy

Low impact strength

High specific volume

Hygroscopicity

KM can also absorb other liquids with high penetrating power, such as aviation kerosene.

Toxicity

During operation, CMs can emit fumes that are often toxic. If products are made from CM that will be located in close proximity to a person (such an example can be the composite fuselage of the Boeing 787 Dreamliner aircraft), then additional studies of the impact of CM components on humans are required to approve the materials used in the manufacture of CM.

Low maintenance manufacturability

Composite materials have low operational manufacturability, low maintainability and high cost operation. This is due to the need to use special labor-intensive methods, special tools for the completion and repair of objects from CM. Often objects from CM are not subject to any modification and repair at all.

Areas of use

Consumer Goods

Characteristic

The technology is used to form additional protective coatings on surfaces in steel-rubber friction pairs. Application of the technology makes it possible to increase the working cycle of seals and shafts of industrial equipment operating in the aquatic environment.

Composite materials are composed of several functionally distinct materials. The basis of inorganic materials is silicates of magnesium, iron, and aluminum modified with various additives. Phase transitions in these materials occur at sufficiently high local loads, close to the ultimate strength of the metal. At the same time, a high-strength cermet layer is formed on the surface in the zone of high local loads, due to which it is possible to change the structure of the metal surface.

armor for military vehicles

Literature

Vasiliev VV Mekhanika konstruktsii iz kompozitsionnykh materialov [Mechanics of constructions from composite materials]. - M.: Mashinostroenie, 1988. - 272 p.
Karpinos D. M. Composite materials. Directory. - Kyiv, Naukova Dumka

Notes

Links

Wikimedia Foundation. 2010 .

Composite materials

Composite material (composite, KM) - an inhomogeneous solid material consisting of two or more components, among which reinforcing elements can be distinguished that provide the necessary mechanical characteristics of the material, and a matrix (or binder) that ensures the joint operation of the reinforcing elements.

The mechanical behavior of the composite is determined by the ratio of the properties of the reinforcing elements and the matrix, as well as the strength of the bond between them. The efficiency and performance of the material depend on the correct choice of the initial components and the technology of their combination, designed to provide a strong bond between the components while maintaining their original characteristics.

As a result of combining the reinforcing elements and the matrix, a complex of composite properties is formed, which not only reflects the initial characteristics of its components, but also includes properties that isolated components do not possess. In particular, the presence of interfaces between the reinforcing elements and the matrix significantly increases the crack resistance of the material, and in composites, unlike metals, an increase in static strength does not lead to a decrease, but, as a rule, to an increase in fracture toughness characteristics.

Advantages of composite materials

It should be noted right away that CMs are created for the performance of these tasks, therefore, they cannot contain all the possible advantages, but when designing a new composite, the engineer is free to set him characteristics that are significantly superior to the characteristics of traditional materials when fulfilling this goal in this mechanism, but inferior to them in any other aspects. This means that CM cannot be better than the traditional material in everything, that is, for each product, the engineer performs all the necessary calculations and only then chooses the optimum between materials for production.

high specific strength
high rigidity (modulus of elasticity 130…140 GPa)
high wear resistance
high fatigue strength
it is possible to make dimensionally stable structures from CM

Moreover, different classes of composites may have one or more advantages. Some benefits cannot be achieved simultaneously.

Disadvantages of composite materials

Most classes of composites (but not all) have disadvantages:

high price
property anisotropy
increased science intensity of production, the need for special expensive equipment and raw materials, and therefore a developed industrial production and scientific base of the country

Areas of use

Consumer Goods

mechanical engineering

Characteristic

Specifications

The protective coating, depending on the composition of the composite material, can be characterized by the following properties:

thickness up to 100 microns;
shaft surface cleanliness class (up to 9);
have pores with sizes of 1 - 3 microns;
friction coefficient up to 0.01;
high adhesion to the surface of metal and rubber.

Technical and economic advantages

A high-strength cermet layer is formed on the surface in the zone of high local loads
The layer formed on the surface of polytetrafluoroethylenes has a low coefficient of friction and low resistance to abrasive wear;
Metal-organic coatings are soft, have a low coefficient of friction, porous surface, the thickness of the additional layer is a few microns.

Application areas of the technology

drawing on work surface seals to reduce friction and create a separating layer that prevents rubber from sticking to the shaft during the rest period.
high speed engines internal combustion for auto and aircraft industry.

Aviation and astronautics

Armament and military equipment

Due to their characteristics (strength and lightness), composite materials are used in the military for the production of various kinds armor :

armor for military vehicles

Composite materials. Properties of composite materials

2. Spraying.

3. Pultrusion.

4. Winding.

5. Pressing.

6. SMC technology.

7. RTM method (Resin Transfer Molding).

Composites classification

Advantages of composite materials

Disadvantages of composite materials

High price

Property anisotropy

Low impact strength

High specific volume

Hygroscopicity

Toxicity

Low maintenance manufacturability

Areas of use

Consumer Goods

Characteristic

Literature

see also

Notes

Links

Advantages of composite materials

Disadvantages of composite materials

Areas of use

Consumer Goods

mechanical engineering

Characteristic

Specifications

Technical and economic advantages

Application areas of the technology

Aviation and astronautics

Armament and military equipment

see also

Links

hand molding

Spraying

RTM (injection)

Vacuum infusion

winding

pultrusion

direct pressing

Autoclave molding

Composite products

What else to read

THE LAST NOTES

Categories