ICEI - 2022 (Volume 10 - Issue 11)

To Study The Tribological Property Evaluation of Aluminium 7050 Reinforced with B4C and Mos2 Composites

DOI : 10.17577/IJERTCONV10IS11054

Download Full-Text PDF Cite this Publication
Bangarappa L, 2022, To Study The Tribological Property Evaluation of Aluminium 7050 Reinforced with B4C and Mos2 Composites, INTERNATIONAL JOURNAL OF ENGINEERING RESEARCH & TECHNOLOGY (IJERT) ICEI – 2022 (Volume 10 – Issue 11),

Text Only Version

To Study The Tribological Property Evaluation of Aluminium 7050 Reinforced with B4C and Mos2 Composites

Bangarappa L

Department of Mechanical Engineering, University Visvesvaraya College of Engineering, Bengaluru, India

Abstract Composite materials are made of more than one material which is mixed at microscopic level and which are chemically insolvable. The main reason for selecting the Aluminum composite is based on its excellent mechanical properties such at high strength and low weight which is thebasic requirement of aerospace applications also for the automotive applications. Matrix materials 7xxx series is one of the best materials in the Aluminum family. Among 7xxx series Al7050 is good with high strength to weight ratio which is more preferred in aeronautical applications with more than 92% of the in as-cast state. The density of Al7050 is 2.83 g/cm3. Fabrication of composite is done by stir casting method which is a liquid state technique for the production of composite materials. In this the elements are mixed in a molten matrix with the help of stirring activity. Stir casting is simple and cost-effective method of fabricating composite. The Al7050 reinforced with B4C andMoS2 composite is prepared with stir casting.

All the tests results give that the wear rate is high in as cast samples of Al7050. But the wear rate goes on decreasing with increase in weight percentage of B4C and MoS2 reinforcement in Al7050 matrix. B4C is known for best wear resisting materials. The MoS2 materialis known for its properties like good chemical stability and thermal stability. So presence of B4C and MoS2 in composite reduces the wear rate and also preferred for the various aerospace and automotive applications.

Keywords Al7050 Matrix materials series, stir casting method, B4C and MoS2 composite, pin-on-disc wear testing setup, SEM analysis, load, velocity and sliding distance.

  1. INTRODUCTION

    Network materials 7xxx arrangement is perhaps the best material in the aluminum family. Among 7xxx arrangement Al7050 is acceptable with high solidarity to weight proportion which is more favoured in aeronautical applications with over 92% of the in as-cast state.

    In this procedure especially mix throwing process is progressively helpful to create aluminum composite with B4C and MoS2. Circulation of B4C and MoS2 particles in aluminum lattice is all the more testing one due to their non- uniform dispersion and their interfacial contact zone when contrast with other fortification materials [1, 2]. Since the expansion of B4C and MoS2 particles with aluminum combination lattice impacts tribological property of the composites, the levels of weight fractions of B4C and MoS2 are chosen dependent on the application prerequisite.

    The accompanying variable boundaries are to be thought of while setting up the metal grid composites by mix throwing process. Such boundaries are speed of turn, mixing temperature, support preheat temperature, mixing speed, blending time, pouring temperature, impeller sharp edge point, impeller position, feed rate, and so on are to be kept up for accomplishing great mechanical properties of metal network composites.

    1.1 Aluminum 7050

    Aluminum 7050 is a heat treatable composite that has high tribological properties and high resistance to wear rate. This material is well known in aviation businesses. The vast majority of the Aluminum 7050 in plate structure has the thickness over 2 inches. The primary structures of Aluminum 7050 are as per the following 2.3% Mg 2.302%, Zn 6.308%, Zr 0.1220%, Si

    0.121%, Fe 0.15%, Mn 0.103%, Ti 0.062%,

    Aluminium Balance volume

    1.2. Wrought Aluminum alloy designation system

    The table 1 illustrates the alloy designation system for wrought Al,

    Table 1 Wrought Aluminum designation system

    Alloy series

    Principal alloying element

    1xxx

    99.000% minimum Al

    2xxx

    Cu

    3xxx

    Mn

    4xxx

    Si

    5xxx

    Mg

    6xxx

    Mg and Si

    7xxx

    Zn

    8xxx

    Other elements

    This chief alloying component is added to the Aluminum combination. This term additionally portrays the Aluminum composite arrangement. i.e., 1000 arrangement, 2000 arrangement, 3000 arrangement, 4000 arrangement,

    5000 arrangement, 6000 arrangement, 7000 arrangement and 8000 arrangements as appeared in above table.

    The second single digit (xXxx), on the off chance that it is not quite the same as 0, demonstrates an alteration of the particular amalgam. The self-assertive numeric value given

    to notify a particular combination present in the arrangement is shown by third and fourth digits.

    Model: In composite 6185, the number '6' demonstrates that it is of the magnesium and silicon combination arrangement, the '1' shows that it is the primary alteration to the first amalgam 6085 and the '85' recognizes it in the 6xxx arrangement. The main special case to this numbering framework is with 1xxx arrangement Aluminum composites which is an unadulterated Aluminum. For this situation the last two digits give the base Aluminum rate above 99%. That is compound 1450 with 99.50% least Aluminum.

      1. Aluminum alloys and their characteristics

        1. 1xxx series alloys: These series alloys are non- heat treatable. These alloys have the UTS about 69 to 186MPa. This series contains 99.00% Al so this series is called as pure Aluminum series. These alloys are selected for fabrication due to their excellent corrosion opposition and thermal resistance. These alloys are utilized for fabrication of specialized chemical tanks and pipings. These alloys have relatively poor mechanical qualities due to lose bonding.

        2. 2xxx series alloys: These series alloys are warmth treatable. These alloys have the UTS about 186 to 428MPa. These are Aluminum/copper alloys. It has the Cu addition range about 0.7 to 6.8%. These are peak level performance series and high strength alloys which are often used for aviation and aircraft applications.

          These materials have good strength to resist the large range of temperature. In these series some alloys are having the weld able property and some are not weld able. So it requires different welding processes such as arc welding processes.

        3. 3xxx series alloys: These series alloys are able to non-heat treatment with UTS of 110 to 283Mpa. These alloys are composed with Al/Mn alloys. It has the Mn addition range about 0.05 to 1.81%. These alloys have moderate strength; have good corrosion resistance and good formability. These alloys are utilized for elevated temperatures. These alloys are the main components today for heat controllers as heat exchanger in power plants and automotives. These base alloys have ability to weld with 4xxx, 1xxx and 5xxx series filler materials.

    1. 4xxx series alloys: These arrangement amalgams have ability of both heat treatment and non- heat treatment with extreme rigidity of 172 to 379Mpa. These composites are Al/Si combinations. It has the silicon expansion run about 0.6 to 21.51%. These have main arrangement which contains both warmth treatable and non-heat treatable amalgams. Silicon expansion in Al lessens it is dissolving point and improves its ease when it is in liquid stage. This arrangement f combinations is increasingly utilized as material called filler.

    2. 5xxx series alloys: These arrangement combinations are non-heat treatable. It has a definitive rigidity around 124 to 352Mpa. These amalgams are the Aluminum/Magnesium composites. It has the

      magnesium expansion go about 0.2 to 6.22%. These arrangements had the most elevated quality of non-heat treatable amalgams. This compound is promptly welded capable. These combinations are utilized for wide range applications, for example, transportation, spans, transport structures, structures and weight vessels.

    3. 6xxx series alloys: These arrangement alloys are heat treatable. It has the UTS about 124 to 400Mpa. These alloys are the Al/Mg-Si alloys. It has the magnesium and silicon additions around 0.1%. These combinations are fused in numerous basic components. These amalgams are normally cementing break delicate. Consequently, they not to be circular segment welded without fillermaterial. These compounds have ability to weld with both 4xxx and 5xxx arrangement filler materials based on the application and administration necessities.

    4. 7xxx series alloys: These arrangement alloys are heat treatable. It has the UTS about 221 to 607Mpa. These alloys are the composition of Al/Zn alloys. This alloy was utilized in high performance requirement for example aviation and sporting equipments. These alloys are unsuitable candidates for arc welding.

  2. OBJECTIVES AND METHODOLOGY

      1. Objectives

        Objective is the goal or object of any efforts and actions. Objectives lead to the activities towards achieving goals of the project work. Objectives provide the guidelines to perform any work. Following are some important objectives,

        1. Fabrication of the composite Al7050 reinforced with B4C and MoS2.

        2. To evaluate the tribological property of the composite Al7050 reinforced with B4C and MoS2.

        3. To analyze the samples by SEM image.

        1. Fabrication of the composite

          Fabrication of composite includes the objective of deciding the sample composition. Sample composition is determined from the different sets of samples to study the alternative solutions. Different sample composition sets helps to conduct the comparative study of behavior of the material. The sample composition used in this project is mentioned in below table 2,

          Table 2 Sample composition used in this project

          Set number

          Al 7050 (%)

          B4C

          (%)

          MoS2 (%)

          Number of samples

          1.

          100

          0

          0

          9

          2.

          98

          1

          1

          9

          3.

          96

          2

          2

          9

          4.

          94

          3

          3

          9

          Once the sample composition is decided then the fabrication of the samples is to be done with the help of proper casting method. Casting of samples is done by

          choosing the proper casting process. In this project by considering the various literature reviews we have chosen the stir casting process to cast the sample.

          The casting of samples is in the form of circular rods of diameter 10 to 12 mm with any length based on the number of samples. It is also the one of important objective of the project work to do efficiently. Optimization techniques are implied to choose the optimized casting activity. Stir casting process is easy and economical processof casting the MMC.

        2. To evaluate the tribological property

    To evaluate the tribological property the samples are tested on pin on disc wear testing setup for the study of worn-out percentage of samples. The main parameters of the pin on disc wear test are speed, distance and load. These parameters are kept constant for specific set of samples and varied for every sample. In pin-on-disc setup the main objective is to achieve the contact between the sample and that of the rotating disc. After the test conducted on the pin- on-disc setup further study of material behavior is studied. The wear property is evaluated as a tribological property in this project.

  3. EXPERIMENTAL DETAILS

    Fabrication is composite is done various casting methods. But stir casting is a liquid phase technique for the production of composite materials, in these the elements are mixed in a molten matrix by the help of stirring activity. Stir casting is simple and cost-effective method of fabrication. Main parts of stir casing setup are motor, furnace, crucible and stirring blades [3].

      1. Stir casting setup

        Stir casting setup consists of a feeder for reinforcing material, mechanical stirrer and furnace. The furnace was utilized to heat and melt the material.

        The stirrer was utilized to frame the vortex that drives the blending of the support materials those are presented in dissolve. Stirrers comprises of the blending bar and the impeller cutting edge.

        Figure 1: Line diagram of the stir casting.

        Base pouring heater is utilized for creation of metal grid composites in mix throwing process procedure which gives moment pouring of the soften blend. Figure 1shows the courses of action of mix throwing process.

      2. Casting Procedure

        1. The first and most significant step of mix throwingincludes softening the Al.

        2. During the softening process, Al softens responsesto the environment and dampness and originates afilm of Al2O3 as stated by following equation.

        3. This film covers the surface of the melt from further response with environment.

        4. Then mix throwing process includes blending of dissolve, the melt is mixed continuously which exposes the melt surface to the environment whichtend to continuous oxidation of aluminium melt in mix throwing process.

        5. Addition of wetting agents for example Mg, Borax and TiK2F6 in the dissolve. Figure 1 shows steps involved in stir casting.

      3. Mechanical stirrer

        The stirrer is combined with the changing rate engine to limit the stirrer velocity. The three primary states of stirrer are single stage; two-fold stage and multi stage impeller. Two-fold step and multi-step stirrer are fundamentally utilized in compound ventures while single step impeller stirrer is regularly utilized for manufacture of aluminum grid composites (AMC's) and half and half aluminum framework composites (HAMC's). Figure 2 showsthe phases of impeller stirrer.

        Figure 2 various stages of mechanical impeller stirrer.

      4. Stirring time

        Blending time is a progressively noteworthy procedure boundary in mix throwing process. Higher blending time may prompt the disfigurement of the hardened steel stirrer cutting edge at extremely high working temperature. While lower mixing time may prompt bunching of particles fortification and results in non-homogenous conveyance of support particles. In this way, ideal benefit of mixing time is basic. For Al/Sic composites the analysts recommends that 10mins time is an ideal benefit of mixing to accomplish better conveyance of support.

      5. Feed rate

        Stirrer from swirl and fortification of elements is distribution in the focal point of the swirl. Low feed rate is hard to accomplish because of the development of pieces of little strong particles. High feed rate brings about centralization of particles in the composites. Therefore, choice of ideal pace of taking care of is significant. Therefore, the ideal pace of taking care of is in scope of

        0.78-1.49 grams/sec to maintain a strategic distance from the amassing of fortification in the composite and accomplish uniform scattering of support particles all through the composites.

      6. Wear

        It is a proces in which the material loss takes place at the surface due to some mechanical actions which leads to the reduction of weight fraction of the samples in percentage. Wear can be reduced by using thermal spray coatings. In thermal spray coating process the hard material with wear resistance properties and high corrosion resistance is sprayed on the base metal.

        3.6.1 Pin-on-disc

        Pin-on-disc is an important setup for the characterization and analysis of the tribological property like wear. Pin-on-disc is a lab process for determining the wear of samples during sliding motion under contact using a pin moving on a rotating disc.

      7. Pin-on-disc experiment steps

        Pin on disc testing setup is utilized for tribological properties study. The test steps are presented as follows;

        1. The first step is to check the weight of sample by using higher precision digital weighing machine.

        2. Pin surface is made level with the end goal that it will bolster the heap over its whole cross area called as second step. This was accomplished by cleaning the pin test ground by utilizing emery paper of 80 coarseness size before testing.

        3. The third step is to avoid the initial turbulence period associated with wear curves and friction.

        4. The fourth step is the genuine testing called consistent state wear. This stage is the dynamic rivalry between move of material from pin onto the plate and development of wear flotsam and jetsam and their ensuing evacuation.

        5. At the initial stage of each experiment, precaution steps are taken to make sure that load is applied in normal direction.

        f. Then the final step is to check the weight

        loss of the samples. After removing the sample

        from the setup it was cleaned with acetone reagent. Then each sample is weighed by using the digital weighing machine. Then the specific wear rates of the samples are obtained by following equation [4-5],

        W= (wl)/(LxS.D)

        Where,

        W= specific wear rate (mm3/N-m). S D = sliding distance (m).

        Wl=weight loss of samples (Grams) =Density of

        the worn sample (Grams/mm3).

        L = Applied load (N).

      8. Wear calculations

        1. Velocity = Sliding Distance/ Time

        2. Time= Sliding Distance/ Velocity

        3. Density of Composite = (Al x VAl) + (B4C x VB4C) + (MoS2 x V MoS2)

        4. Weight loss = Initial weight Final weight.

        5. Volume loss= Weight loss / Density

        6. Specific wear rate (SWR)=Volume loss/ Load x sliding distance

      9. Applications of pin on disc wear testing setup

    1. The pin on disc setup is applicable in research, product development and quality assessment.

    2. It is applicable in quality assessment of lubricants and additives.

    3. It is applicable in researches for mining technology development with wear characterization of the materials.

    4. It can also be used to research and quality assessment related space, metal forming and plastics.

  4. RESULTS AND DISCUSSION

      1. Wear Test

        The main aim of the tests is to find out the control factors which influence the minimum specific wear rate. A conventional method was chosen to develop the experiments [6]. The as cast Al 7050 alloy and Al 7050 alloy with different weight fraction of B4C and MoS2 are subjected to wear test below with the help of pin on disc wear test setup. The wear tests were conducted on 10mm diameter and 30mm long solid cylindrical samples against rotating steel disc of EN-32 type [7]. The wear is measured with respect to load, velocity and sliding distance. The process parameters for the tests are shown in illustrated table 3.

        Table 3 Process Parameters for the wear testing

        Levels

        Parameters

        Unit

        1

        2

        3

        4

        5

        Load

        N

        10

        20

        30

        40

        50

        Sliding Velocity

        m/ s

        0.5

        1.0

        1.5

        2.0

        2.5

        Sliding Distance

        m

        500

        1000

        1500

        2000

        2500

        1. Wear test for load variation

          The main purpose is to analyze the most contributing factors of weight of B4C and MoS2 with 0%, 1%, 2% and 3% on wear rate. The results of wear test for all

          compositions for load variation are shown in below tables 4 and 5 [8-9].

          Load (N)

          SV

          (m/s)

          SS

          (rpm)

          SD

          (m)

          ST

          (sec)

          I W

          (g)

          FW

          (g)

          W L

          (g)

          Volume loss (mm3)

          SWR

          (mm3/Nm) (x10-3)

          A06 L1 = 10

          1.5

          287

          1500

          1000

          6.131

          6.097

          0.033

          0.0010

          1.07

          A01 L2 = 20

          1.5

          287

          1500

          1000

          6.132

          6.098

          0.011

          0.0011

          1.12

          A07 L3 = 30

          1.5

          287

          1500

          1000

          6.134

          6.006

          0.128

          0.0011

          1.12

          A03 L4 = 40

          1.5

          287

          1500

          1000

          6.241

          6.108

          0.133

          0.0012

          1.20

          A02 L5 = 50

          1.5

          287

          1500

          1000

          6.193

          5.953

          0.240

          0.0013

          1.36

          Table 4 Results for wear test of as cast samples for load variation.

          From the graph it is clear that the wear rate of as cast, 1% and 2% composition is copious higher than that of 3% composition material. So, the conclusion of the test is the as the volume fraction of reinforcement increases the wear rate goes on decreases. So, the composite with 3% of reinforced B4C and MoS2 in Al 7050 is better for wear resistance for load variation [12, 13, 14].

        2. Wear test for velocity variation

          As the tests for load variation are done in the previous section, in this segment the tests are conducted to investigate the influence of velocity on SWR. The tests are conducted on 10milimeter diameter and 30mm length solid cylindrical examples onrotating steel disc. The wear is measured with respect to velocity, load and sliding distance [15-16].

          Table 6 Results for wear test of as cast samples forvelocity variation

          6.103

          Velo city (m/s)

          Load (N)

          SS

          (rpm

          )

          SD

          (m)

          ST

          (se)

          I W

          (g)

          FW

          (g)

          WL

          (g)

          Volume loss(m m3)

          SWR

          (mm3/N m) (x10- 5)

          A01S1

          =0.5

          30

          95.5

          1500

          3000

          6.098

          6.092

          0.005

          0.0020

          5.5329

          A02 S2

          =1.0

          30

          191

          1500

          1500

          5.953

          5.939

          0.013

          0.0048

          6.6792

          A03 S3

          =1.5

          30

          287

          1500

          1000

          6.108

          0.004

          0.0453

          7.06675

          A06 S4

          =2.0

          30

          382

          1500

          750

          6.117

          6.107

          0.010

          0.0037

          6.402

          A04S5

          =2.5

          30

          573

          1500

          500

          6.241

          6.182

          0.039

          0.0209

          4.65646

          Table 5 Results for wear test of Al-98%+B4C-1%+MoS2- 1% samples for load variation.

          Loa d (N)

          SV

          (m/s)

          SS

          (rpm)

          SD

          (m)

          ST

          (sec)

          I W

          (g)

          FW

          (g)

          WL

          (g)

          Volume loss (mm3)

          SWR

          (mm3/Nm)(x10-

          3

          )

          A11 L1 = 10

          1.5

          287

          1500

          1000

          6.208

          6.138

          0.069

          0.0010

          1.02

          A14 L2

          =20

          1.5

          287

          1500

          1000

          6.278

          6.111

          0.166

          0.0010

          1.03

          A16 L3

          =30

          1.5

          287

          1500

          1000

          6.268

          6.154

          0.114

          0.0010

          1.06

          A17 L4

          =40

          1.5

          287

          1500

          1000

          6.192

          6.137

          0.055

          0.0011

          1.14

          A18 L5

          =50

          1.5

          287

          1500

          1000

          6.311

          5.917

          0.393

          0.0012

          1.25

          Table 7 Results for wear test of Al-98%+B4C-1%MoS2- 1% samples for velocity variation

          Velocity m/s

          Load N

          SS

          rpm

          SDm

          ST

          sec

          IW

          g

          F W

          g

          WL

          g

          Volume loss(mm3)

          SWR

          (mm3/Nm) (x10-5)

          A11 S1

          =0.5

          30

          95.5

          1500

          3000

          6.17

          6.16

          0.009

          0.0032

          4.23149

          A14 S2

          =1.0

          30

          191

          1500

          1500

          6.15

          6.14

          0.003

          0.0010

          4.83984

          A16 S3

          =1.5

          30

          287

          1500

          1000

          6.17

          6.17

          0.002

          0.0329

          5.33149

          A17 S4

          =2.0

          30

          382

          1500

          750

          6.15

          6.14

          0.009

          0.0032

          4.4975

          A18S5= 2.5

          30

          573

          1500

          500

          5.91

          5.72

          0.191

          0.0670

          2.22696

          Effects of input parameters such as weight percentage, load, time rate of distance travel and sliding distance on wear rate [10, 11]. The below figure 3 shows the results of wear test for 0%, 1%, 2% and 3% composition.

          Figure 3: Load Vs SWR for different weight percentage ofB4C and MoS2 in Al 7050.

          Effects of input parameters such as weight percentage, load, time rate distance travel and sliding distance on wear rate [17, 18]. With the help of graph of load versus SWR it was easy to comprehend the most influencing parameters for the different composition of the composite material. The below

          fig 5 shows the velocity versus specific wear rate for 0%, 1%, 2% and 3% composition.

          Figure 4: Velocity Vs SWR for different weight percentageof B4C and MoS2 in Al 7050

        3. Wear test for Sliding Distance variation

          As the tests for load and velocity variations are done in the previous section, in this section the test is done on composite to check the influence of sliding distance on the wear rate. Basically, from works I came to know that the presence of B4C and MoS2 will reduce the wear rate with respect to increase in the weight percentage of reinforcement [19]. In this section, as cast Al 7050 alloyand Al 7050 alloy with different weight fraction of B4C and MoS2 particles are subjected to wear test with the help of pin on disc wear testing setup.

          For every type of composite sample tests are done at 5 different sliding distance levels such as 500m, 1000m, 1500m, 2000m and 2500m possession the load and velocity constant at 30N and 1.5m/s respectively.

          Table 8 Results for wear test of as cast samples for sliding distance variation.

          Table 9 Results for wear test of Al-98%+B4C- 1%+MoS2-1% samples for sliding distance variation

          SD

          m

          Lo

          adN

          Velocity

          m/s

          SS

          rpm

          ST

          sec

          I W

          g

          F

          W

          g

          WL

          g

          Volum

          e loss mm3

          SWR

          mm3/N mx10-3

          A12 D1 = 500

          30

          1.5

          287

          334

          6.21

          6.16

          0.04

          0.0307

          1.27769

          A13 D2 = 1000

          30

          1.5

          287

          667

          6.21

          6.17

          0.03

          0.0126

          2.1260866

          A15 D3 = 1500

          30

          1.5

          287

          1000

          6.21

          6.14

          0.06

          0.0332

          3.14522

          A19 D4 = 2000

          30

          1.5

          287

          1334

          5.64

          5.63

          0.01

          0.0391

          3.6783

          A11 D5= 2500

          30

          1.5

          287

          1667

          6.16

          6.09

          0.07

          0.0251

          3.59257

          As conduct the several experiments on Al 7050 as cast and Al 7050 alloy with different weight percentage such as 1%, 2% and 3%. I observed the results and relevant graphs. The factors such as velocity, load and SD influences the wear rate on the composite. The presence of B4C and MoS2 will decrease the wear rate on each influencing parameter. The wear rate is high in as cast samples because the strength of as

          S D

          m

          Lo adN

          Velocity m/s

          SS

          rpm

          ST

          sec

          I W

          g

          F W

          g

          WL

          g

          Volume loss m m3

          SWR

          mm3/ Nm x10-3

          A04 D1

          = 500

          30

          1.5

          287

          334

          6.24

          6.16

          0.07

          0.027

          2.1987

          A05 D2

          = 100

          0

          30

          1.5

          287

          667

          6.19

          6.10

          0.08

          0.029

          3.1430

          A08 D3= 150

          0

          30

          1.5

          287

          1000

          6.11

          6.07

          0.04

          0.053

          3.5621

          A09 D4

          = 200

          0

          30

          1.5

          287

          1334

          6.09

          6.04

          0.05

          0.019

          3.8841

          A01 D5= 250

          0

          30

          1.5

          287

          1667

          6.09

          6.05

          0.03

          0.014

          4.0446

          cast Al 7050 is low as compare to the strength with 3% reinforcement of B C and MoS . The wear rate goes on

          4 2

          decreasing with increase in the weight percentage of B4C and MoS2 due to the strong bonding strength between matrix and reinforcement. Byobserving the results, the conclusion is the wear rate by eachinfluencing parameter on 3% reinforcement is less because of the bonding strength and it is preferred to the use in the industries.

          Al 7050/B4C and MoS2 composite examples were presented to microstructure appraisal to evaluate its properties. By utilizing new emery papers with various evaluations the examples are cleaned to acquire the fine the surface completion. The best reagent called Keller's reagentwas used on the sample for engraving the sample surface to see the microstructure. Interfacial and solid interfacial holding between the network and support (B4C and MoS2) metal grid composite assumes a significant job in deciding the impacting factors on wear pace of the composites. The higher volume portion of particles of support is relied upon to produce the more noteworthy warm burdens. Bunches can shape high warm burdens and lead to wear at the surface. The examination gives that the surface wear is seen in the Al 7050/B4C and MoS2 composites having higher volume division of fortification, for example, 2% and 3% which are appeared in figure (a, b, c and d).

          Figure 5 (a, b, c and d) shows the SEM pictures of wear trash of Al 7050/B4C and MoS2 composites. Anyway, the morphology of the wear particles didn't rely upon B4C and MoS2 volume portion. The well-used surfaces of Al 7050/B4C and MoS2 composite half and half composite was primarily equal shallow scratches demonstrating gentle scraped spot. What's more, the break of oxidized layer and plastic distortion are likewise watched.

  5. CONCLUSIONS

        1. The Al 7050 reinforced with B4C and MoS2 composite was successfully fabricated by stir casting process. Stir casting method is easier and economical.

        2. Tribological property was increased because of the addition of B4C and MoS2 which go about as successful fortification in aluminum.

        3. The wear rate goes on decreasing with increase in weight percentage of B4C and MoS2 because of higher bonding strength between matrix and reinforcement.

        4. SEM is used to study the sample surface at microscopic level and investigate the properties.

5 Fabrication of composite is done by stir casting method which is a liquid state technique for the production of composite materials. In these the elements are mixed in a molten matrix with the help of stirring activity. Stir casting is simple and cost effective method of fabricating composite. The Al7050 reinforced with B4C and MoS2 composite is prepared with stir casting.

6 Samples of Al7050 reinforced with B4C and MoS2 are subjected to wear test by utilizing the pin-on-disc wear testing setup. The process parameters for the tests are taken as load, velocity and sliding distance. The tests are done with five levels for variation of all three parameters. Then specific wear rate is calculated by utilizing the data of weight loss. Then some samples are subjected to SEM analysis to evaluate the properties byanalyzing the SEM images.

REFERENCES

[1] J.Hashim, L.Looney, M.S.J. Hashmi, Metal matrix composites: production by the stir casting method, Journal of Materials Processing Technology 92-93 (1999) 1-7.

[2] Stanly Jayaprakash, J., Priyadarsini, M.J.P., Parameshachari, B.D., Karimi, H.R. and Gurumoorthy, S., 2022. Deep Q-Network with Reinforcement Learning for Fault Detection in Cyber-Physical Systems. Journal of Circuits, Systems and Computers, 31(09), p.2250158.

[3] S.Rama rao. G. Padmanabhan, Fabrication and mechanical properties of aluminium-boron carbide composites, international journal of materials and biomaterials applications (2012) 15-18.

[4] Mahendra boopathi, k.p. arulshiri N. Iyandurai, Evaluation of tribological properties of aluminum alloy 2024 reinforced with silicon carbide and fly ash metal matrix composites, American journal of applied sciences, 10(2013),219-229.

[5] Pankaj Sharma, Amit kumar Bindal Development of mechanical and metallurgical behavior of Al-Sic reinforced metal matrix composite IJAERA, Volume-2, issue-4, August-2016, Department of mechanical Engineering, GNIT, Mullana, Ambala, India.

[6] Bryan Harris, Engineering composite materials, The Institute of Materials, London, (1999).

[7] Prashantha Kumar HG, Anthony Xavior M. Graphene reinforced metal matrix composite (GRMMC): a review.Procedia Engineering. 2014; 97:10331040.

[8] Charles S, Arunachalam V, Effect of particle inclusions on the mechanical properties of composites fabricated by liquid metallurgy (2003).

[9] Prabu S.B, Karunamoorthy L, Kathiresan S, Mohan B, Influence of stirring speed and stirring time on distribution of particles in cast metal matrix composite, Journal of material processing technology 171(2) (2006) 268-273.

[10] Characterization of silicon carbide reinforce aluminium matrix composites Md.Habiur Rahman, H.M.Mamun Al Rashed. ELSEVIER 10th International Conference on Mechanical Engineering, ICME 2013.

[11] Mahagundappa M. Benal, H.K. Shivanand, Effects of reinforcements content and ageing durations on wear characteristics of Al (6061) based hybrid composites, Journal of Wear, Vol. 262, pp.

[12] Venkatesan S, Anthony Xavior M. Wear characteristicsstudies on graphene reinforced AA7050 based composite. Mater Res Express 2019;

[13] I.A. Ibrahim, F.A.Mohamed and E.J. Lavernia.

[14] Particulate Reinforced Metal Matrix Composites Review, J. Mater. Sci.,26(5), p 11371156. 1991.

[15] P. Rohatgi. Cast Metal Matrix Composites: Past, Present and Future, AFS Trans., ,109, p 1133. 2001.

[16] Boopathi, Evaluation of low-cost Aluminum Composites for Aircraft Engine Structural Applications, NASA Tech. Memo. No. 83357, Washington, DC, 1983.

[17] Deravaju, The strength of MMCs Reinforced with Randomly oriented Discontinuous Fibers, Mett. Tran. Vol. 23A, Nov. 1992, pp 3045-3053.

[18] Manoj Singla, D. Deepak Dwived, Lakhvir Singh, Vikas Chawla,

Development of Aluminium Based Silicon Carbide Particulate Metal Matrix Composite , Journal of Minerals & Materials Characteriz.

[19] S. V. Prasad, B. D. McConnell, Tribology of aluminum metal-matrix composites: lubrication by graphite. Wear, 149 (1991) 241-253.

[20] M. Singla, L. Singh and V. Chawla, Study of Wear Properties of Al- SiC Composites, Journal of Minerals and Materials Characterization and Engineering, Vol. 8, No. 10, 2009, pp. 813-821.