Most engineering materials can be classified into one of three basic categories.
1-metals
2-ceramics
3-polymers
-In addition to the three basic categories there are
v
v
4-composites : that can be defined as a nonhomogeneous mixtures of the three types
In this topic i will talk about
Composites
A materials system composed of two or more physically distinct phases whose combination produces aggregate properties that are different from those of its constituents
•Examples:
-Cemented carbides (WC with Co binder)
-Plastic molding compounds containing fillers
-Rubber mixed with carbon black
-Wood (a natural composite as distinguished from a synthesized composite)
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Composites can be very strong and stiff, yet very light in weight, so ratios of strength‑to‑weight and stiffness‑to‑weight are several times greater than steel or aluminum
Fatigue properties are generally better than for common engineering metals
Toughness is often greater too
Composites can be designed that do not corrode like steel
Possible to achieve combinations of properties not attainable with metals, ceramics, or polymers alone .
-------------------------
One Possible Classification of Composite Materials
1-Traditional composites – composite materials that occur in nature or have been produced by civilizations for many years
-Examples: wood, concrete, asphalt
2-Synthetic composites - modern material systems normally associated with the manufacturing industries, in which the components are first produced separately and then combined in a controlled way to achieve the desired structure, properties, and part geometry
---------------------------
Components in a Composite Material
Nearly all composite materials consist of two phases:
1-Primary phase - forms the matrix within which the secondary phase is imbedded
2-Secondary phase - imbedded phase sometimes referred to as a reinforcing agent, because it usually serves to strengthen the composite
* The reinforcing phase may be in the form of fibers, particles, or various other geometries
-----------------------
Our Classification Scheme for Composite Materials
1-Metal Matrix Composites (MMCs) ‑ mixtures of ceramics and metals, such as cemented carbides and other cermets
2-Ceramic Matrix Composites (CMCs) ‑ Al2O3 and SiC imbedded with fibers to improve properties, especially in high temperature applications
The least common composite matrix
3-Polymer Matrix Composites (PMCs) ‑ thermosetting resins are widely used in PMCs
-Examples: epoxy and polyester with fiber reinforcement, and phenolic with powders
Typical uses of composites are monocoque structures for aerospace and automobiles, as well as more mundane products like fishing rods and bicycles. The stealth bomber was the first all-composite aircraft, but many passenger aircraft like the Airbus uses an increasing proportion of composites in its fuselage. The quite different physical properties of composites gives designers much greater freedom in shaping parts, which is why composite products often look different to conventional products. On the other hand, some products such as drive shafts, helicopter rotor blades, and propellers look identical to metal precursors owing to the basic functional needs of such components.
...................................................................
..................................
All this information are from books and sites talk about mechanics
and this is just a Research
1-metals
2-ceramics
3-polymers
-In addition to the three basic categories there are
v
v
4-composites : that can be defined as a nonhomogeneous mixtures of the three types
In this topic i will talk about
Composites
A materials system composed of two or more physically distinct phases whose combination produces aggregate properties that are different from those of its constituents
•Examples:
-Cemented carbides (WC with Co binder)
-Plastic molding compounds containing fillers
-Rubber mixed with carbon black
-Wood (a natural composite as distinguished from a synthesized composite)
-------
Composites can be very strong and stiff, yet very light in weight, so ratios of strength‑to‑weight and stiffness‑to‑weight are several times greater than steel or aluminum
Fatigue properties are generally better than for common engineering metals
Toughness is often greater too
Composites can be designed that do not corrode like steel
Possible to achieve combinations of properties not attainable with metals, ceramics, or polymers alone .
-------------------------
One Possible Classification of Composite Materials
1-Traditional composites – composite materials that occur in nature or have been produced by civilizations for many years
-Examples: wood, concrete, asphalt
2-Synthetic composites - modern material systems normally associated with the manufacturing industries, in which the components are first produced separately and then combined in a controlled way to achieve the desired structure, properties, and part geometry
---------------------------
Components in a Composite Material
Nearly all composite materials consist of two phases:
1-Primary phase - forms the matrix within which the secondary phase is imbedded
2-Secondary phase - imbedded phase sometimes referred to as a reinforcing agent, because it usually serves to strengthen the composite
* The reinforcing phase may be in the form of fibers, particles, or various other geometries
-----------------------
Our Classification Scheme for Composite Materials
1-Metal Matrix Composites (MMCs) ‑ mixtures of ceramics and metals, such as cemented carbides and other cermets
2-Ceramic Matrix Composites (CMCs) ‑ Al2O3 and SiC imbedded with fibers to improve properties, especially in high temperature applications
The least common composite matrix
3-Polymer Matrix Composites (PMCs) ‑ thermosetting resins are widely used in PMCs
-Examples: epoxy and polyester with fiber reinforcement, and phenolic with powders
Typical uses of composites are monocoque structures for aerospace and automobiles, as well as more mundane products like fishing rods and bicycles. The stealth bomber was the first all-composite aircraft, but many passenger aircraft like the Airbus uses an increasing proportion of composites in its fuselage. The quite different physical properties of composites gives designers much greater freedom in shaping parts, which is why composite products often look different to conventional products. On the other hand, some products such as drive shafts, helicopter rotor blades, and propellers look identical to metal precursors owing to the basic functional needs of such components.
...................................................................
..................................
All this information are from books and sites talk about mechanics
and this is just a Research
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