Karthick .p3rd year mech

Phone number:9655309471

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A composite material is a combination of two or more chemically distinct materials to form a stronger material.

The term “composite” broadly refers to a material system which is composed of a discrete constituent (the reinforcement) distributed in a continuous phase (the matrix), and which derives its distinguishing characteristics from the properties of its constituents, from the geometry and architecture of the constituents, and from the properties of the boundaries (interfaces) between different constituents.

Composite materials are usually classified on the basis of the physical or chemical nature of the matrix phase, e.g., polymer matrix, metal-matrix and ceramic composites.

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1. To fabricate 7075Al/SiCp composites through stir casting technique2. To study tensile strength of 7075Al/SiCp composites3. To study impact strength of 7075Al/SiCp composites4. To study hardness of 7075Al/SiCp composites5. To study micro structure of composite materials

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• High performance aluminium centric material systems. The reinforcement inAMCs could be in the form of continuous/discontinuous fibres, whisker or particulates, in Aluminium matrix composites (AMCs) refer to the class of light weight volume fractions ranging from a few percent to 70%.• Aluminum matrix composites (AMCs) have been widely studied since the 1920s. • They offer a large variety of mechanical properties depending on the chemical composition of the Al-matrix. They are usually reinforced by Al2O3, SiC, C but SiO2, B, BN, B4C, AlN may also be considered

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STIR CASTING PROCESS• One of the prominent and economical route for development and processing of metal matrix composites materials.• Properties of these materials depend upon many processing parameters and selection of matrix and reinforcements. Literature reveals that most of the researchers are using 2, 6 and 7075 aluminum matrix reinforced with SiC particles for high strength properties whereas, insufficient information is available on reinforcement of "Al2O3" particles in 7075 aluminum matrix.

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• Tensile test• Impact test• Hardness test • Microscopic test

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SNO SIZE OF THE SPECIMEN

LOAD IN JOULES

12345678

1515151520202020

1816182028262432

IMPACT TEST

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SNO

MATERIAL

MINLOADkgf

MAX LOADkgf

SCALE

R.H.NO

12345678

1515151520202020

6060606060606060

100100100100100100100100

B BBBBBBB

90 75927173656661

9091958974858277

9489919086797274

HARDNESS TEST:

Avg

91.38592.683.377.676.673.370.6

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s.no Material

Peak load in KN

Displacement at FMAX

In mm

Breaking load in KN

Max displacement in mm

Area in sq.mm

Ultimate stress in KN/sq.mm

UTS in mpa

1 5m-10%

12.434

7.160 3.830 7.350 50.286

0.247 247

2 5m-15%

12.294

9.440 2.201 9.710 50.286

0.244 244

3 5m-20%

16.947

11.608

2.637 15.590

50.286

0.337 337

Tensile test:

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Microstructure of the composites

ADDITION OF sic-10%

ADDITION OF sic-15%

ADDITION OF sic- 20%

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(1) Brake rotors for German high speed train and made from a particulate reinforced aluminum alloy. Compared to conventional parts made out of cast iron with 120 kg/piece, the 76 kg of the AMC rotor offers an attractive weight saving potential.

(2) The braking systems (discs, drums, calipers or back-plate) of the New Lupo from Volkswagen made from particulate reinforced aluminum alloy supplied by Duralcan.

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(3) AMC continuous fiber reinforced pushrods produced by 3M racing engines. These pushrods weigh 40% as much as steel, are stronger and stiffer, and have high vibration damping.

(4) AMC wires also developed by 3M for the core of a electrical conductors. The unique properties of this type of conductor offer substantial performance benefits when compared to the currently used steel wire reinforced conductors.

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Greater strength

Improved stiffness

Reduced density(weight)

Controlled thermal expansion coefficient

Thermal/heat management

Improved abrasion and wear resistance

Control of mass (especially in reciprocating applications)

Improved damping capabilities.

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Thank you

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