Shahid Report.docx

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

Chapter:- 1 INTRODUCTION 1.1 Need for the composite material In the 21st century, high strength, lightweight and energy efficient materials have received extensive attention, since the problems of environment and energy are major threshold areas. In order to fulfill this requirement, engineers and researchers are striving to develop new and better engineering materials. The modern engineering material finds wide application in the aerospace, defense field, engineering industry, automobile and leisure industry. The performance and efficiency for these applications can be increased largely by the application of modern engineering materials

1.2 History of composites Materials science has developed rapidly during the last century to meet the needs for better materials which has tailored properties, enhanced performance and reliability in defense, aerospace, engineering, structures and automobile application. But its main support has come from the newer technologies associated with aircraft, automobile, missiles, space research and in the engineering industry. The increasing demand for lightweight, a stiff and strong material to withstand conditions not previously experienced by man-made components and to perform functions have not been previously envisaged. Some of these requirements were able to be met by improvements in existing methods of manufacture and treatment of well-tried materials. The first major structural metal matrix composite material system was Boron/Aluminum (B/Al), which was developed in the late 1960s. To date, the only production applications are the tubular struts used in NASA's Space Shuttle Orbiter mid fuselage. However many airframe, engine component and other items of B/Al have demonstrated the weight savings of 20 to 65 percent. There

is

also

considerable

research

in

Boron/Titanium,

Graphite/Aluminum

and

Graphite/Magnesium systems which were developed show significant potential in DEPARTMENT OF MECHANICAL ENGINEERING

Page 1

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

structural applications. New fibers such as SiC were developed in the mid 1970s and coatings for carbon, boron fibers were made as viable additives for metallic matrices. The addition of a ceramic reinforcing phase such as SiC-fibers in a metal matrix such as aluminum produces a composite with a coefficient of thermal expansion (CTE) below that of the matrix metal itself. In addition, long, continuous fibers of SiC, carbon or boron can dramatically increase the modulus of the component over that of the unreinforced matrix. Adding 30% continuous carbon fiber to aluminum matrix will increase the modulus of the metal. By the mid 1990s, a variety of MMCs was found in spacecraft applications: Carbon-reinforced copper was used in the combustion chamber of rockets, SiC-reinforced copper was used in rocket nozzles, Al2O3-reinforced aluminum composites were used in the fuselage and SiC- reinforced aluminum composites were used for wings and blades. The antenna boom on the Hubble Space Telescope was made of a graphite-aluminum composite. The cost of producing MMCs has prevented them from entering into other marketplaces. A notable exception is again in the area of sports equipment, where MMCs such as Duralcan (Al reinforced with 10% Al,O3 particulates) and Al reinforced with 20 % SiC particulates were used in bicycle frames for lightweight, high strength, very expensive mountain bikes. Honda has used aluminum metal matrix composite for the cylinder liners in some of their engines; B21A1, H22A, H23A and C32B. Toyota has used metal matrix composites in the Yamaha designed 2ZZ-GE engine which is used in Toyota car. All major automotive components like space frames, exterior and interior body panels, instrument panel assemblies, power plants, power trains, drive trains, brake and steering systems etc. are now being fabricated with a wide variety of composites that include polymer, metal and ceramic matrix composites. Every industry is now vying with each other to make the best use of composites. The present trend is to use composites in many disciplines starting from sports goods to space vehicles. This worldwide interest during the last four decades has led to the prolific advancement in the field of composite materials and structures.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 2

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

1.3

2018

The definition of a composite. The term composite means composed, therefore it should be material that is composed of

two or more components. However, this would mean that most natural and synthetic materials and alloys belong to this category. The definition should be clarified.

Matrix + Reinforcement = Composite

1.4 Classification of composites, Composites are classified based on matrix material as follows,

Figure No : 1

DEPARTMENT OF MECHANICAL ENGINEERING

Page 3

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

Figure No : 2

DEPARTMENT OF MECHANICAL ENGINEERING

Page 4

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

1.5

2018

Metallic Matrix composites, Metals are extremely versatile engineering materials. A metallic material can exhibit a wide

range of readily controllable properties through appropriate selection 0f alloy composition and thermo mechanical processing method. Metal matrix composites (MMCs) are materials, which combine a tough metallic matrix with a hard ceramic reinforcement to produce composite materials with superior properties to conventional alloys (Barnes et al. 1999). Composites consist of one or more discontinuous phases embedded in a continuous phase. The discontinuous phase is usually harder and stronger than the continuous phase and is called the ‘reinforcement’ or ‘reinforcing material’, where as the continuous phase is termed the ‘matrix’. The metal matrix composite, on the other hand, has a series of advantages that are very important in the utilization of structural materials. These advantages relate to the same metallic properties that have led to the general primacy of metal alloys for use in dynamic engineering structures and they include the combination of the following properties: 1. High strength. 2. High modulus. 3. High toughness and impact properties. 4. Low sensitivity to changes in temperature or thermal shock. 5. High surface durability and low sensitivity to surface flaws. 6. High electrical and thermal conductivity. 7. Excellent reproducibility of conductivity. 8. Excellent technological background with respect to (a) Design, (b) Manufacture, (c) Shaping and forming, (d) Joining, (e) Finishing and (f) Service durability information.

1.5.1 Matrix Phase Matrix is a solid which can be processed so as to embed and adherently grip the reinforcement and matrix should not react chemically or metallurgically with the reinforcement. DEPARTMENT OF MECHANICAL ENGINEERING

Page 5

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

The role of the matrix material comprises the following:  Distributes the stress to the reinforcement material.  Provides the final shape of the composite part.  Binds the reinforcements (fibers/particulates) together.  Mechanically supports the reinforcements.  Protects the reinforcements from surface damage due to abrasion or chemical attacks.

1.5.2 Classification of metal matrix composites

Figure No : 3

1.6 Aluminium Matrix Composites (AMCs) Many Al-MMCs are more suitable for higher temperature operations than un-reinforced alloys. The aim is also to get improved strength, stiffness, fatigue strength, thermal conductivity, abrasion resistance, creep resistance and dimensional stability. The reinforcement is typically a ceramic material. The Al-MMCs can be classified based on the structure of the reinforcements. There are continuous fibers, short and particle strengthened materials. The particulate metal matrix composites can be fabricated partly by the already existing production investments and can be produced at a lower cost. DEPARTMENT OF MECHANICAL ENGINEERING

Page 6

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

Aluminium alloys have a high machinability index and have been enormously used in aerospace and automobile industries due to their superior properties such as higher strength to weight ratio, excellent low-temperature performance, exceptional corrosion resistance, chemical inertness to commonly used cutting tools, etc. However, the main weaknesses of aluminium alloys are their poor high-temperature performance and wear resistance. To overcome these problems, aluminium alloys reinforced by ceramic particles, known as metal matrix composites (MMCs), have been developed (Pramanik et al. 2008). Aluminium is the most popular matrix for the metal matrix composites (MMCs). The Al alloys are quite attractive due to their low density, their capability to be strengthened by precipitation, their good corrosion resistance, high thermal and electrical conductivity, and their high damping capacity. Aluminium Matrix Composites (AMCs) offer superior combination of properties (profile of properties) in such a manner that today no existing monolithic material can be a rival. Over the years, AMCs have been tried and used in numerous structural, non-structural and functional applications in different engineering sectors. The key benefits of AMCs in the transportation sector are lower fuel consumption, less noise and lower airborne emissions. With increasing stringent environmental regulations and emphasis on improved fuel economy, use of AMCs in transport sector will be inevitable and desirable in the coming years. AMCs are intended to substitute monolithic materials including aluminium alloys, ferrous alloys, titanium alloys and polymer based composites in several applications. It is now recognized that in order that AMCs substitute for monolithic materials in engineering system to be wide spread, there is a compelling need to redesign the whole system for weight reduction and volume savings. Moreover, by utilizing near-net shape forming and selective-reinforcement techniques AMCs can offer economically viable solutions for a wider variety of commercial applications. Recent successes in commercial and military applications of AMCs are based partly on such innovative changes made in the component design. Composite materials should include component materials which complement each other and are compatible. With these composites, the high-modulus reinforcement is combined with a matrix that has been selected for its ease of fabrication into structural hardware. In addition, there is little chemical or mechanical interaction between the two phases, which simplifies matrix DEPARTMENT OF MECHANICAL ENGINEERING

Page 7

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

reinforcement compatibility problem. With metal matrix composites, the temperature of composite fabrication is generally much higher, and the composite has elastic modulus by one or two orders of magnitude higher than those of the matrices. Chemical compatibility has been solved in metal matrix composites in two ways: either by using low temperature fabrication techniques or by selecting thermodynamically stable component phases which are at equilibrium with each other. A corresponding thermal mechanical compatibility problem has been solved either by using ductile matrix that yields and takes up all the differential strain necessary in thermal cycling or by selecting a matrix and reinforcement that have nearly matching thermal expansion coefficients.

1.7 Polymeric Matrices. Polymeric matrices are the most common type in production. In comparison with metals they have low weight, high strength, are corrosion resistant, do not require surface treatment, absorb vibrations and have low thermal and electrical conductivity. The mechanical properties vary according to the type of polymer, whether it is a thermoplastic, thermo set or elastomer. For the production of composites all three types of polymers are used. Thermoplastics are mostly chemically resistant and tougher than thermo sets, while for elastomers, the dominant feature is its elongation. Due to their low density, they are most widely used in aircraft design. The disadvantage is the low thermal stability of polymers. The most important composites have a thermoset matrix.

1.8 Ceramic Matrices. Ceramics is inorganic non-metallic heterogeneous material consisting of crystalline substances of varying composition and configuration. Ceramic materials generally have good chemical resistance, lows thermal conductivity, a high melting point, high hardness and compression strength and are electrically non-conductive. The main disadvantage is the considerable brittleness, poor workability, and high sensitivity to internal defects. They are suitable for use at high temperatures.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 8

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

1.9 The composition of a composite. A composite material is composed primarily of a matrix, i.e. a continuous phase, which is armored with a reinforcement (reinforcement is a secondary phase), which is usually the discontinuous phase.

1.9.1 The matrix. The matrix combines the individual particles of reinforcement, protecting them against external influences and prevents their violation. The basic function of the matrix is to transmit the external load onto the reinforced phase. For the matrix, a good bond strength with the reinforcing phase material (i.e. perfect wet ability without chemical interaction at the interface of the matrix and reinforcement) is required. Among other requirements for the matrix, a low weight is commonly included. In comparison with the reinforcement phase, a matrix has generally lower strength and greater plasticity.

1.9.2 The reinforcement. Reinforcement is the strong, stiff integral component which is incorporated into the matrix to achieve desired properties. The term ‘reinforcement’ implies some property enhancement. Reinforcement may be particle, whisker or fiber. Reinforcement increases the strength, stiffness and the temperature resistance capacity and lowers the density of MMC. In order to achieve these properties the selection depends on the type of reinforcement, its method of production and chemical compatibility with the matrix and the following aspects must be considered while selecting the reinforcement material. 

Size – diameter and aspect ratio



Shape – Chopped fiber, whisker, spherical or irregular particulate, flake, etc



Surface morphology – smooth or corrugated and rough



Poly or single crystal



Structural defects – voids, occluded material, second phases

DEPARTMENT OF MECHANICAL ENGINEERING

Page 9

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES



2018

Inherent properties – strength, modulus and density.

Even when a specific type has been selected, reinforcement inconsistency will persist because many of the aspects cited above in addition to contamination from processing equipment and feedstock may vary greatly. Selection criteria for the ceramic reinforcement include 

Elastic modulus,



Tensile strength,



Density,



Melting temperature,



Thermal stability,



Coefficient of thermal expansion,



Size and shape,



Compatibility with matrix material, and



Cost

1.10 ALUMINUM ALLOY: Aluminium alloys are alloys in which aluminium (Al) is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon and zinc. There are two principal classifications, namely casting alloys and wrought alloys, both of which are further subdivided into the categories heat-treatable and non-heat-treatable. Alloys composed mostly of the two lightweight metals aluminium and magnesium have been very important in aerospace manufacturing since somewhat before 1940. Aluminium-magnesium alloys are both lighter than other aluminium alloys and much less flammable than alloys that contain a very high percentage of Selecting the right alloy for a given application entails considerations of its tensile strength, density, ductility, formability, workability, weld ability, and corrosion resistance. Aluminium alloys typically have an elastic modulus of about 70 GPa, which is about one-third of the elastic modulus of most kinds of steel and steel alloys. Therefore, for a given load, a component or unit made of an aluminium alloy will experience a greater elastic deformation than a steel part of the DEPARTMENT OF MECHANICAL ENGINEERING

Page 10

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

identical size and shape. Though there are aluminium alloys with somewhat-higher tensile strengths than the commonly used kinds of steel, simply replacing a steel part with an aluminium alloy might lead to problems. Aluminium alloys are widely used in automotive engines, particularly in cylinder blocks and crankcases due to the weight savings that are possible. Since aluminium alloys are susceptible to warping at elevated temperatures, the cooling system of such engines is critical.

1.10.1

WROUGHT ALLOYS

The International Alloy Designation System is the most widely accepted naming scheme for wrought alloys. Each alloy is given a four-digit number, where the first digit indicates the major alloying elements.  1000 series are essentially pure aluminium with a minimum 99% aluminium content by weight and can be work hardened.  2000 series are alloyed with copper, can be precipitation hardened to strengths comparable to steel. Formerly referred to as duralumin, they were once the most common aerospace alloys, but were susceptible to stress corrosion cracking and are increasingly replaced by 7000 series in new designs.  3000 series are alloyed with manganese, and can be work hardened.  4000 series are alloyed with silicon. They are also known as sliming.  5000 series are alloyed with magnesium.  6000 series are alloyed with magnesium and silicon, are easy to machine, and can be precipitation hardened, but not to the high strengths that 2000 and 7000 can reach.  7000 series are alloyed with zinc, and can be precipitation hardened to the highest strengths of any aluminium alloy.  8000 series is a category mainly used for lithium alloys.

1.11 The use of composites. For fields such as rocketry and aviation, the automotive and chemical industries, electrical constructions and many other areas, composites are indispensable in a variety of applications today. DEPARTMENT OF MECHANICAL ENGINEERING

Page 11

2018

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

1.11.1 Uses of 6000 series  6061-T6 is one of the most commonly used 6000 series aluminum alloys (see 6061 aluminium alloy)  6063 is an aluminium alloy, with magnesium and silicon as the alloying elements. The standard controlling its co mposition is maintained by The Aluminum A sociation. s It has generally good mechanical properties and is heat treatable and wieldable. It is similar to the British aluminium alloy HE9.  6063 is mostly used in extruded shapes for architecture, particularly window frames, door m frames, roofs, and sign fra

es. It is typically produced with very smooth surfaces fit for

anodizing.

1.12

Material Properties.

Base Matrix – Al6061

Properties of Al 6061

DEPARTMENT OF MECHANICAL ENGINEERING

Density

2.7 g/cm3

Poisson’s ratio

0.33

Young’s modulus

68.9 GPa

Tensile strength

124-290 MPa

Melting point

585 0C

Page 12

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

Fig 4.Al6061

DEPARTMENT OF MECHANICAL ENGINEERING

2018

Table No : 1

Page 13

2018

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

Reinforcement – KBF4 Properties of KBF4 Density

2.505 g/mL at 25 °C(lit.)

Fig 5. KBF4

Melting point

530 0C

Assay

96%

Form

Powder

Table No : 2

Reinforcement – K2TiF6 Properties of K2TiF6

Fi Kg.6. K2TiF6

DEPARTMENT OF MECHANICAL ENGINEERING

Density

300 g/cm3

Melting point

780 0C

Boiling point

235-237 0C

Form

Powder

Table No : 3

Page 14

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

1.5 SUMMARY We studied need for the composite material by studying this we known that people and industries requires light weight and high strength material for different applications like in aerospace industries, automobile industries etc. we studied history of composite, by studying this we known that different technologies has been arrived, to enhance the strength of material with low weight. We studied the definition of composite and their classification based on reinforcement and based on metal matrix composites and then we studied definition of reinforcement, metal matrix with their classification, in that we choose AMCs for our project concerned. We Al-alloy wrought alloy, uses of composite, We choose base matrix as AL6061. Reinforcement as TiB2, halides as KBF4 and K2TiF6 for our project concerned.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 15

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

Chapter. 2 LITERATURE SURVEY In the recent years the researcher have given more attention to in-situ composites mainly because of its clean interface formed between the matrix with reinforcement , high bonding strength , good interfacial integrity , uniform distribution in the matrix with high mechanical properties and low fabrication costs. Because of its uniform distribution in the matrix , the in-situ AMC are mainly used in structured application , when high strength to weight ratio is plays important role in the aircraft industries and automotive chassis. In previous studies ultra-fined ceramic reinforcement with the AMC have been report,

Title of the paper : Microstructure Evolution and Mechanical Properties of Al-TiB2/Tic In Situ Aluminum-Based Composites during Accumulative Roll Bonding (ARB) Process Authors

:

Jinfeng Nie , Fang Wang , Yusheng Li , Yang Cao , Xiangfa Liu.

Material Used

:

Al-TiB2/Tic.

Methodology

:

Stir casting process.

Abstract

:

This kind of Al-TiB2/Tic in situ composite was successfully prepared using the melt reaction method and the accumulative roll-bonding (ARB) technique.

Conclusion

:

The fracture surface of Al-TiB2/Tic composites showed many dimples, indicating ductile-type fracture. Most of the TiB2 and TiC reinforcement particles were located in the centers of the dimples.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 16

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

Title of the paper : Analysis of Factors Influencing Hardness of Al-TiB2 Composites Using Response Surface Methodology. Authors

: Jenarthanan M. P, Ramesh Kumar S, Pradeep M.

Material Used : Al-TiB2. Methodology : Response Surface Methodology. Abstract

:

Aluminium matrix reinforced with titanium diboride (TiB2) yield superior properties than the aluminium alloy reinforced with other particulates such as Al2O3, Sic, and Tic.

Conclusion

: The value of hardness increases much as the composition of TiB2 increases and the optimum hardness is obtain in stirrer speed 400rpm and 2% composition of Mg.

Title of the paper : Al 6061-TiB2 Metal Matrix Composite Synthesized with Different Reaction Holding Times by In-Situ Method Authors

:

Lawrance C. A.1, P. Suresh Prabhu.

Material Used

:

Al 6061-TiB2.

Methodology : Stir casting process. Abstract

:

Al 6061 and TiB2 using in-situ technique where halide salts namely potassium hexaflurotitanate (K2TiF6) and potassium tetrafluroborate (KBF4) were introduced in the Al 6061 melt at 850°C.

Conclusion

:

AL 6061-TiBmetal matrix composites were synthesized successfully by incorporating halide salts, K2TiF6 and KBF4 in the Al 6061 alloy at 850°C.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 17

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

Title of the paper : Study of Mechanical Properties and Microstructure of Aluminum Alloy Reinforced with TiB2, by in Situ Technique. Authors

: Akshay Mohan Pujar and Chetan Kulkarni.

Material Used : Aluminum Alloy Reinforced with TiB2. Methodology : Stir casting process. Abstract

: In preparing the samples for microstructure, wear,hardness and tensile testing a square plate of size (0.15 m / 0.15 m / 0.065 m)was cast using the sand casting method.

Conclusion

: The wear properties of the Al6061 alloy were improved by the addition of TiB2 particulates, The wear resistance of composites increased with decreasing particle size of TIB2 particulates.

Title of the paper : Corrosion Characterization of Al-Cu Reinforced In-Situ TiB2. Authors

:

R. Rosmamuhamadan,, S. Sulaiman, M.A. Azmah Hanim M.I.S. Ismail.

Material

Used

:

Al-Cu

Reinforced

TiB2.

Methodology : Stir casting process. Abstract

:

Aluminium-copper (Al-Cu) alloy was reinforced with 3 and 6wt.% titanium diboride (TiB2). Al-MMCs has been fabricated with salt route reaction process at 800 °C via potassium hexafluorotitanate (K2TiF6) and potassium tetrafluoroborate (KBF4) salts.

Conclusion

:

The composition of 3wt.%TiB2 gave the best corrosion rate compare to cast Al-Cualloy which were 16.15 and 22.50 x 10-3 mm/y.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 18

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

Title of the paper : A Comparative Study on the Microstructures and Mechanical Properties of Al 6061 Alloy and the MMC Al 6061/TiB2/12P Authors

: T.V. Christy1, N. Morgan and S. Kumar.

Material Used : Al 6061/TiB2. Methodology : Stir casting process. Abstract

:

Al 6061 alloy with Al–TiB2 metal matrix composite containing 12% by weight TiB2 manufactured through the in-situ process was presented.

Conclusion

: Strings as well as particulate agglomerates were present as distinct micro structural features of the composite.

Title of the paper :

Comparative Analysis Of Aluminium Metal Matrix Composites Reinforced With Tic And TiB2 Using Stir Casting Process.

Authors

:

S. Venkatesan, M. Anthony Xavier.

Material Used

:

Al 6061-TiB2.

Methodology

:

Stir Casting Process.

Abstract

:

Influence of Titanium carbide and Titanium boride reinforcements in different percentages with the aluminum composites were prepared by stir casting process and analysed mechanical characterization and wear characteristics.

Conclusion

:

A TiB2 particulate reinforced magnesium matrix composite was successfully fabricated by adding a TiB2–Al alloy and using the stir casting technique obtained uniform dispersion of reinforcement.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 19

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

Title of the paper

:

2018

In-situ metal matrix composite steels: Effect of alloying and annealing on morphology, structure and mechanical properties of TiB2 particle containing high modulus steels.

Authors

:

R. Aparicio-Fernandez, H. Springer, A. Szczepaniak, H. Zhang, D. Raabe.

Material Used :

Al-TiB2

Methodology

:

Stir casting method.

Abstract

: Morphology, size and dispersion of TiB2 particles formed in-situ from FeTiB2 based melts, as well as their chemical composition, crystal structure and mechanical properties.

Conclusion

: Increase the stiffness/density ratio of steels, where found to be drastically changed by the alloying additions andadditional annealing treatments.

Title of the paper

:

A study of microstructure and wear behavior of TiB2/Al metal matrix composites.

Authors

:

A. Sreenivasan, S. Paul Vizhianb, N.D. Shivakumar, M. Muniraju, and M. Raguraman

Material Used

:

Al-TiB2.

Methodology

:

Stir casting method.

Abstract

:

Aluminium metal matrix composites (MMCs). Matrix alloys with 5, 10 and15% of TiB2 were made using stir casting technique.

Conclusion

:

The observed wear rate was higher for the unreinforced aluminum alloy when compared to the Al/TiB2 reinforced composites.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 110

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

Title of the paper

:

2018

Mach inability Study of Al-5Cu-TiB In-situ Metal Matrix 2

Composites Fabricated by Flux-assisted Synthesis. Authors

:

A.Mahamani.

Material Used

:

Al-TiB2.

Methodology

:

Stir casting method.

Abstract

:

This work is an attempt to understand the machinability behavior of the Al-5Cu-TiB2 in-situ metal matrix composites .The focus of this study is to investigate the effect of the cutting speed and feed rate on flank wear, cutting force, and surface roughness.

Conclusion

:

The increase in cutting speed increased the flank wear, reduced the cutting force, and minimized the surface roughness.

Title of the paper

:

Wear and Friction Behavior of Stir Cast Al-TiB2 Metal Matrix Composites with Various Lubricants

Authors

: S. Poria . Sutradhar, P. Sahoo.

Material Used : Al-TiB2. Methodology : Stir casting method. Abstract

:

a multi-tribotester using block-on-roller configuration under 25-75 N loads and 400-600 rpm rotational speeds. Four different weight percentages of TiB2 are considered in this study.

Conclusion

: during sliding against steel surface by higher weight percentage of TiB2composites. It leads to relatively smoother surface morphology of wear tracks which is confirmed by SEM images. In case of lower weight percentage of TiB2-composites.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 20

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

Title of the paper : Wear performance optimization of stir cast Al-TiB2 metal matrix composites using Taguchi design of experiments. Authors

: Suswagata Poria,, Prasanta Sahoo, and Goutam Sutradhar

Material Used

: Al-TiB2.

Methodology

: Stir casting process.

Abstract

: Different weight percentages of micro-TiB2 powders with average sizes of 5-40micron are incorporated into molten LM4 aluminium matrix by stir casting method.

Conclusion

: In comparison to conventional base alloys or metals, MMCs also able to provide improved strength, high elasticity, high stiffness.

Title of the paper : Effect of TiB2 content on microstructure and mechanical properties of in-situ fabricated TiB2/B4C composites. Authors

: WANG Yu-jin, PENG Hua-xin, YE Feng1, ZHOU Yu.

Material Used : TiB2/B4C. Methodology

: Stir casting process.

Abstract

: The fully dense boron carbide matrix composites containing 10%/40% (volume fraction) TiB2(TiB2/B4C) were in-sit fabricated via chemical reaction of B4C, TiO2 and graphite powders at 2050°C under a pressure of 35MPa.

Conclusion

: The fracture toughness increases steadily with increasing TiB2 content, reaching the maximum value of8.2MPa/m1/2 at 40% (volume fraction).

DEPARTMENT OF MECHANICAL ENGINEERING

Page 21

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

Title of the paper :

2018

Quantitative study of particle size distribution in an in-situ grown Al–TiB2 composite by synchrotron X-ray diffraction and electron microscopy.

Authors

:

Y. Tang , Z. Chen, A. Borbély, G. Ji , S.Y. Zhong , D. Schryvers , V. Ji , H.W.Wang.

Material Used

:

Al-TiB2.

Methodology

:

Stir casting method.

Abstract

:

TiB2 particles are well crystallized and free of crystal defects. The average particle size determined from different Bragg reflections by the restricted moment method ranges between 25 and 55nm,where the smallest particle size is determined using the 110 reflection .

Conclusion

:

TiB2 particles are well crystallized and have negligible dislocation density. Good agreement was found between the results obtained from the restricted moment and multiple whole profile fitting procedure.

Title of the Paper

Effect of cooling rate and other factors on size and pattern of distribution :

of TiB2 particles formed during solidification of the Al- TiB2 melt for various pouring temperatures

Authors

:

P.Senthil Kumar, P.R.Lakshminarayanan, R.Varahamoorthi

Material Used :

Al-TiB2

Methodology

:

Stir casting method.

Abstract

:

Conclusion

:

Aluminium alloy is melt in a graphite crucible and two salts , potassium hexaflour titanate and potassium tetra fluro borate are dropped at a slow rate and mixed with aluminium melt, with the help of a hand held graphite stirrer. When fluidity is more the circulation will be more and at the same time if the cooling rate is very high more number of TiB2 particles will be trapped and observed in that location.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 22

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

Title of the paper : Effect on size and pattern of distribution of TiB2 particles formed during solidification of the Al-TiB2 MMC. Authors

: P.Senthil Kumar , P.R.Lakshminarayanan

Material Used : Al-TiB2. Methodology : Stir casting process. Abstract

: aluminium (A356) alloy is melt in a graphite crucible and two halide salts (ie), potassium hexa fluro titanate and potassium tetra fluroborate are dropped at a slow rate and mixed with aluminium melt, with the help of a hand held graphite stirrer.

Conclusion : When the cooling rate and local turbulence are very high at a particular location of the casting the presence of the TiB2 particles are also found to be more.

Title of the paper : Production and Characterization of Al 6061–TiB2 In – situ Metal Matrix Composite. Authors

: Lawrance C.A1 and Dr. P. Suresh Prabhu.

Material Used : Al 6061–TiB2. Methodology : Stir casting process. Abstract

: Using halidesalts namely potassium hexafluro titanate (K2TiF6) and potassium tetrafluro borate (KBF4) an attempt has been made to investigate the degree of in-situ reaction in the synthesis of Al 6061 – TiB2 metal matrix composite.

Conclusion

:

Volume of cryolite slag increases with reaction holding time. Variation in the weight percentage of TiB2 will take place because of change in the volume of cryolite slag.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 23

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

Title of the paper : Analysis on Tensile Strength of Al/TiB2 MMCs in FEA for Different Mould Conditions. Authors

: C. Rajaravi, P.R. Lakshminarayanan.

Material Used : Al-TiB2. Methodology : Stir casting process. Abstract

: Fabricated different pouring temperatures with permanent and sand mould conditions through chemical reactions between Aluminium, Titanium and Boron bearing salts and to test in terms of mechanical property.

Conclusion : The tensile strength of the Al 6% wt while the temperature poring temperature increase tensile strength is also increase.

Title of the paper : Corrosion of Metal-Matrix Composites with Aluminium Alloy Substrate. Authors

: B. BOBIĆ, S. MITROVIĆ, M. BABIĆ, I. BOBIĆ

Material Used : Aluminium Alloy. Methodology : Stir casting method. Abstract

: The corrosion characteristics of boron-, graphite-, silicon carbide-, aluminaand mica- reinforced aluminium MMCs were reviewed. The reinforcing phase influence on MMCs corrosion rate as well as on various corrosion forms was discussed.

Conclusion : light weight, environmental resistance and favorable mechanical properties has made aluminium alloys very popular for use as a matrix metal However, the addition of the reinforcement particles could significantly alter the corrosion behavior of these materials.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 24

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

Title of the paper:

2018

Effect of Thermo-Mechanical Processing and Heat Treatment on the Tribological Characteristics of Al Based MMC's.

Authors

:

R Keshavamurthy, J Madhu Sudhan, Narasimhe Gowda and R Ananda Krishna.

Material Used

:

Al-TiB2.

Methodology : Thermo-Mechanical Processing and Heat Treatment. Abstract

: Cast aluminium alloy and composite were subjected to open die hot forging process. Alloy and its composites were examined to characteristics hardness and wear test under both primary and secondary processing conditions.

Conclusion : Aluminium alloy & its composite processed under forging conditions exhibit higher wear resistance compared with cast conditions.

2.1

SUMMARY

we observed the some literature survey on composite material number of researchers are done on tensile, compressive, impact and corrosion test. But we choose same topic because this is R&D project, the outcomes value will be given in different some time. that’s way we are selecting mechanical properties on AL-TIB2 composites many of them done research on mechanical properties that’s way are doing project on mechanical properties of AL-TiB2.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 25

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

Chapter. 3 OBJECTIVES OF THE PRESENT WORK The objective of the present work is as follows: 1) Al in-situ composite were fabricated with TiB2 reinforcement (1, 3 and 5 wt.%) via exothermic chemical reaction between molten aluminium alloy and mixed halide salts KBF4 and K2TiF6 at a temperature of 8000C by using stir casting route. 2) Micro structural characterization of Al-TiB2 composite by using Optical microscope or Scanning Electron Microscopy equipped with Energy Dispersive Spectroscopy (SEMEDS). 3) Evaluation of various mechanical properties like tensile, hardness and izod and charpy test of the prepared Al-TiB2insitu composites. 4) Evaluation of corrosion test of the prepared in-situ composites.

3.1 SUMMARY Objectives of our project work is to Al in-situ composites can be fabricated TiB2 reinforcement via exothermic chemical reaction. then Al-TiB2 composite can be characterized by microstructure analysis by using techniques SEM, EDM, XRD, then evaluate mechanical properties of prepared by AL-TiB2.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 26

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

Chapter. 4 PROPOSED METHODOLOGY chemical reaction between KBF4 & K2TiF6 halide salt with Al6061 base matrix in an electrical The present work involved preparing Al6061-TiB2 composites using stir casting method using resistances furnace by using stir casting route( liquid metallurgy route).

In-situ process, In-situ process, process the reinforcement is added internally and forms during the chemical reaction.

Figure No : 4 In-situ fabrication of metal matrix composite is a process, in which dispersed(reinforcing) phase is formed in the matrix as a result of precipitation from the melt during its cooling and solidification.

Ex-situ process,

Figure No : 5 In ex-situ Process reinforcement is added externally to the base matrix.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 27

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

REACTIONS 3Al+2KBF4 3K2TiF6 + 6KBF4+ 10Al

AlB2+2KAlF4 3TiB2+10AlF3+12KF

Molecular Weights. Al

-

K

- 39.0983 g/mol

Ti

-

26.982 g/mol

F - 18.998 g/mol B - 10.811 g/mol.

47.867 g/mol

4.1 Stir casting

Figure : 6 In stir casting we use stirrer to agitate the molten metal matrix. The stirrer is generally made up of a material which can withstand at a higher melting temperature than the matrix temperature. Generally graphite stirrer is used in stir casting. The stirrer is consisting of mainly two components cylindrical rod and impeller. The one end of rod is connected to impeller and other end is connected to shaft of the motor. The stirrer is generally held in vertical position and is rotated by a motor at various speeds. The resultant molten metal is then poured in die for casting. DEPARTMENT OF MECHANICAL ENGINEERING

Page 28

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

Stir casting is suitable for manufacturing composites with up to 30% volume fractions of reinforcement.[1] A major concern in associated with the stir casting is segregation of reinforcement particles due to various process parameters and material properties result in the nonhomogeneous metal distribution. The various process parameters are like wetting condition of metal particles, relative density, settling velocity etc. The distribution of particle in the molten metal matrix is also affected by the velocity of stirrer, angle of stirrer, vortices cone etc. In this method first the matrix metal is heated above its liquid temperature so that it is completely in molten state. After it is cooled down to temperature between liquid and solidus state means it is in a semi-solid state. Then preheated reinforcement particles are added to molten matrix and again heated to fully liquid state so that they mixed thoroughly each other. Electric resistance furnace In stir casting process during solidification of fabricated composite are depends on following factors.  Stirring speed and time  Stirring blade angle  Pouring temperature and solidification rate  Reinforcement’s size, percentage and its relative density

DEPARTMENT OF MECHANICAL ENGINEERING

Page 29

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

4.4

2018

Electrical Resistance Furnace(ERF)

ERF uses principle of indirect heating. Refractory material tightly wounded by wire of metallic alloy(i.e. Kanthal, Nikrothal). 2- AC supply is passed through the wire. Internal resistance opposes the flow of current and hence heat is produced. Heat is passed Through refractory material and by radiation as well as convection this heat is transferred to the charge.

Fig 7.Electrical Resistance Furnace

It is essentially requires for vortex formation for the uniform dispersion of particles. There is a no uniform dispersion of particles in case of no vortex formation.

Fig 11. Aluminium Stir Casting Machine And Graphite stirrer

DEPARTMENT OF MECHANICAL ENGINEERING

Page 30

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

4.5

2018

UNIVERSAL TESTING MACHING

Figure No : 8 A universal testing machine (UST), also known as material testing machine or materials test frame, is used to test the tensile strength and compressive strength of materials. A tensile test also known as tension test, is probably the most fundamental type of mechanical test we can perform on material. Tensile tests are simple, inexpansive, and fully standardized.as the material is being pulled, I will find its strength along with how much it will elongate. A compressive test measuring the maximum amount of compressive load a material can bear before fracture. A test piece, usually in the form of a cube, prism, or cylinder. DEPARTMENT OF MECHANICAL ENGINEERING

Page 31

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

4.6

2018

BRINELL HARDNESS TESTING MACHINE

Figure No : 9

4.7 Impact Testing Machine.

Fig 10 DEPARTMENT OF MECHANICAL ENGINEERING

Page 32

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

4.7

2018

Scanning Electron Microscope

A scanning electron microscope (SEM) is a type of electron microscope that produces images of a sample by scanning the surface with a focused beam of electrons. The electrons interact with atoms in the sample, producing various signals that contain information about the surface topography and composition of the sample. The electron beam is scanned in a raster scan pattern, and the position of the beam is combined with the detected signal to produce an image. SEM can achieve resol u tion better than 1 nanometer. Specimens are observed in high vacuum in conventional SEM,

or in low vacuum or wet conditions in variable pressure or

environmental SEM, and at a wide range of cryogenic or elevated temperatures with specialized instruments.

Fig11. Scanning Electron Microscope

DEPARTMENT OF MECHANICAL ENGINEERING

Page 33

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

4.8

2018

X-ray Diffraction (XRD)

The atomic planes of a crystal cause an incident beam of X-rays to interfere with one another as they leave the crystal. The phenomenon is called X-ray diffraction.

Fig12. X-ray Diffraction

DEPARTMENT OF MECHANICAL ENGINEERING

Page 34

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

4.9 Optical Microscope The optical microscope, often referred to as the light microscope, is a type of microscope that commonly uses visible light and a system of lenses to magnify images of small objects. Optical microscopes are the oldest design of microscope and were possibly invented in their present compound form in the 17th century

Fig 13. Optical Microscope

4.10 SUMMARY In our proposed methodology we have to know in situ ex situ process to prepare TIB2 by using AL6061 as base matrix and KBF4,K2TIF6 as halide salt in electrical resistance furnace using stir casting rout molten TIB2 can be poured into desired shape of mould allow to solidified material can be characterized by micro structure analysis using SEM, XRD, EDS. solidified material can be machined with required dimension using lathe machine preferred specimen can be tested for mechanical properties of different temperature.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 35

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

Chapter. 5

EXPECTED OUTCOMES

1. Microstructure analysis may reveal that fine and clean TiB2 particles distributed uniformly with good interfacial bonding and dislocations was observed throughout the matrix. 2. The XRD patterns revealed the formation of TiB2 particulates without the presence of any other compounds. 3. Mechanical properties may increases with the increase in the weight % of TiB2 content in the base matrix. 4. Tensile strength may increase with increase in the weight % of reinforcement but the ductility of the composites reduces with increasing the reinforcement. 5. Hardness BHN and impact strength may increases increase in the TiB2 reinforcement. 6. Corrosion resistance may increases with the increase in the weight % of TiB2 reinforcement.

5.1 SUMMARY TiB2 distributed uniformly in the base matrix prepared composite can be tested for mechanical properties at different temperature it may shows better performance with increase in the ALB2 content.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 36

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

Chapter. 6

PROGRESS OF THE PROJECT WORK

Sl No

Month

Work Carried out

1

July month

Recent projects Discussed with the guide on agricultural, composites and fabrication

2

August

Literature survey on above topics

3

September

Finalization of the project topic

4

October

Literature survey on composite materials

5

Mid October

Collected information about the Purchasing of the raw material required for preparing composites

6

November

Casting preparation according to the methodology

DEPARTMENT OF MECHANICAL ENGINEERING

Page 37

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

REFERENCES. 1. Jinfeng Nie, Fang Wang, H.W.; Le, Y.K.; Li, X.F. Damping capacity of in situ TiB2 particulates reinforcedaluminium composites with Ti addition. Mater. Des. 2007, 28, 628– 632. 2. Jenarthanan M.P, Ramesh Kumar S and Ranade R.S, Effect of KBF4 and K2TiF6 on precipitation kinetics of TiB2 inaluminium matrix composite, Advanced material letters,2011, 210-216. 3. Lawrance C.A. prabhu1,P. Suresh “An Introduction to Metal Matrix Composites”, Cambridge University Press, Cambridge, pp 1-525, 1995. 4. Akshay Mohan Pujar and Chetan Kulkarni. : Investigation of the precipitation kinetics in an Al6061/TiB2 metal matrix composite. Mater Sci Eng. A. 237, 12–23 (1997). 5. R. Rosmamuhamadan,, S. Sulaiman,M.A A., (2013). Influence of B4C on the tribological and mechanical properties of Al7075–B4C composites. Composites Part B: Engineering 54(0): 146-152. 6. T.V. Christy1, N. Morgan and S. Kumar S. Kumar, M. Chakraborty, B.S. Murty, Wear, 265, 134 (2008) 7. Sharma, S.C., Girish,B., Kamath, R., and Sathish, B.M., (1999) Fractography, Fluidity andTensile Properties of Aluminium/Hematile Particle Composite, Journal of Materials. 8. M.K. Surappa – Aluminium matrix composites: Challenges and opportunities. Sadhana Vol 28, 2003. 9. M.F. Ashby, Materials Selection in Mechanical Design, Butterworth-Heinemann, Burlington, MA, USA, 2005. 10. C.S. Ramesh, R. Keshavamurthy, B.H. Channabasappa, S. Pramod. "Friction and wear Behavior of Ni–P coated Si3N4 reinforced Al6061 composites". Volume 43, Issue 3, March 2010, pp 623–634. 11. V. Basavarajappa, G. Chandramohan, R. Subramanian, and A. Chandrasekar. Dry sliding wear behavior of Al2219/SiC metal matrix composites. Mat.Sci, 24:357–356, 12. C.S. Ramesh, R. Keshavamurthy, B.H. Channabasappa, Abrar Ahmed. "Microstructure mechanical properties of Ni–P coated Si3N4 reinforced Al6061 composites". Materials Scienc and Engineering A 502 (2009) pp 99–106. DEPARTMENT OF MECHANICAL ENGINEERING

Page 38

STUDY OF MECHANICAL PROPERTIES OF AL6061 REINFORCED WITH INSITU TIB2 METAL MATRIX COMPOSITES

2018

13. N. Kumar, G. Gautam, R. K. Gautam, A. Mohan and S. Mohan, ‘Synthesis and Characterization of TiB2 Reinforced Aluminium Matrix Composites: A Review’, Journal of Institute of Engineers India Series D, DOI 10.1007/s40033-015-0091-7. 14. M. Rosso, ‘Ceramic and Metal Matrix Composites: Routes and Properties’, Journal of Material Processing Technology, vol. 175, pp. 364-375, 2006. 15. Y. Sahin, ‘Preparation and some properties of SiC particle reinforced aluminium alloy composites’, Materials and Design, vol. 24, pp. 671- 679, 2003. 16. Suresh, S., N. Shenbag, and Vinayaga Moorthi. "Aluminium-titanium diboride (Al-TiB2) metal matrix composites: challenges and opportunities." Procedia Engineering 38 (2012): 89-97. 17. M.K. Aghajanian, M.A. Rocazella, J.T. Burke, S.D.Keck The Fabrication of Metal Matrix Composites by a Pressureless Infiltration Technique Journal of Material Science 26(1991) 447-454. 18. C.Rajaravi, P,R,Lakshminarayanan. The precipitation of TiB2 in aluminum alloy melts from the exothermic reaction of K2TiF6 and KBF4 halide salts and evaluation of its mechanical properties [C], World Congress on Engineering and Computer Science, San Francisco, USA, 2007: 978−988. 19. B. BOBIĆ, S. MITROVIĆ, M. BABIĆ, I. BOBIĆ VIALA J C. Chemical reactivity of aluminium with boron carbide [J]. J Mater Sci, 1997, 32: 4559/4573. 20. R Keshavamurthy, J Madhu Sudhan, Narasimhe Gowda and R Ananda Krishna, Microstructure and properties of in- situ Al/TiB2 composite fabricated by in-melt reaction method, Metall. Mater. Trans. A 31 (2000) 1959–1964.

DEPARTMENT OF MECHANICAL ENGINEERING

Page 39