Study the Effects of Coating on Slurry-Erosive Wear of INCONEL718 on Copper

Download Full-Text PDF Cite this Publication

Text Only Version

Study the Effects of Coating on Slurry-Erosive Wear of INCONEL718 on Copper

Chunkyraj Khangembam Mechanical Engineering Reva University,

Rukmini Knowledge Park, Yelahanka,, Bangalore 64.

Abstract Machine components are exposed to different types of damages over their lifetime. These components are subjected to wear due to variety of loads and different kinds of environments. These damages reduce durability of the component. Hence high resistance to wear is desirable to achieve high durability and reduce maintenance costs.

Slurry-erosive wear is the kind of wear where there is loss of surface material by the action of particles entertained in a fluid. The wear is due to the hard particles which are forced and moved relative to the solid surface. These wear can be restricted by coating the solid components with proper components.

There are various ways of surface coating of material, Out of many surface modification techniques, plasma spraying stands out as one of the most versatile and technologically sophisticated thermal spraying technique. Plasma spraying is gaining extensive attention in the research fraternity as it has the advantage of applying coatings using different materials such as ceramic, metallic and composite coatings with possibility of controlling the thickness from few microns to few millimeters. Thus produced coatings improve hardness and hence reduce wear.

KeywordsWear, INCONEL 718, Plasma Spray Coating, Slurry erosive wear.

  1. INTRODUCTION

    Copper and its alloys are finding enormous applications in the field of automobile engineering for manufacturing of axles, crankshafts, steering, steering shaft, levers, turbines, aircrafts and heavy vehicle components and building constructions. During working, there is always a relative motion and friction between the metal parts resulting in wear and tear. Due to this many adverse effects will be encountered by the specimen which renders loss of material, excess consumption of power during working, shift in the tolerances, wiping of lubrication etc. To make these alloys of copper further versatile and flexible for various application, and to provide a long life under different environments coatings are applied which provide better service and better quality to the metal pieces.

    Since all the manufacturing and fabrication processes involve the use of copper as the metal removal agent a method has to be adopted to minimize the wear of the copper to a possible extent in working conditions, by which its life should be increased.

    In order to enhance life of these parts, their mechanical properties and tribological properties should be improved. This can be done by reinforcing the metal parts with metal composites or by coating these surfaces with other hard substrates. If we go for reinforcement it changes the material property itself as it is mixed with the base metal and in case if only surface property has to be improved its better to go for coating as it improves property only at surface. And also to avoid excessive cost incurred for reinforcing the metal it is feasible to go for coatings since friction is a surface phenomenon.

    Therefore in the present investigation, a comparative study had been conducted to evaluate the various tribological properties such as wear. To enhance the tribological properties of copper, it was decided to apply INCONEL718 coating on copper by plasma spray coating and study its wear behavior by conducting slurry erosive tests.

  2. METHODOLOGY

    1. Test specimen will be first prepared to the given dimensions by various machining process.

    2. The prepared specimen is to be coated with INCONEL718 by plasma spraying machine.

    3. To carry out slurry erosive tests to assess their tribological properties and behavior under working conditions in slurry erosive wear tester.

    4. Presentation of the test results in the form of tabular columns and graphs with inference and conclusion.

  3. LITERATURE SURVEY

    COATINGS

    Coating is a covering that is applied to the surface of an object, usually referred to as the substrate. In many cases coatings are applied to improve surface properties of the substrate, such as appearance, adhesion, wetability, corrosion resistance, wear resistance, and scratch resistance. In other cases, in particular in printing processes and semiconductor device fabrication (where the substrate is a wafer), the coating forms an essential part of the finished product.

    PLASMA SPRAY COATINGS

    The Plasma Spray Process is basically the spraying of molten or heat softened material onto a surface to provide a coating. Material in the form of powder is injected into a very high temperature plasma flame, where it is rapidly heated and accelerated to a high velocity. The hot material impacts on the substrate surface and rapidly cools forming a coating. This plasma spray process carried out correctly is called a "cold process" (relative to the substrate material being coated) as the substrate temperature can be kept low during processing avoiding damage, metallurgical changes and distortion to the substrate material. The plasma spray gun comprises a copper anode and tungsten cathode, both of which are water cooled. Plasma gas (argon, nitrogen, hydrogen, helium) flows around the cathode and through the anode which is shaped as a constricting nozzle. The plasma is initiated by a high voltage discharge which causes localized ionization and a conductive path for a DC arc to form between cathode and anode. The resistance heating from the arc causes the gas to reach extreme temperatures dissociates and ionises to form plasma. The plasma exits the anode nozzle as a free or neutral plasma flame which is quite different to the Plasma Transferred Arc coating process where the arc extends to the surface to be coated. When the plasma is stabilized ready for spraying the electric arc extends down the nozzle, instead of shorting out to the nearest edge of the anode nozzle. This stretching of the arc is due to a thermal pinch effect. Cold gas around the surface of the water cooled anode nozzle being electrically non- conductive constricts the plasma arc, raising its temperature and velocity. Powder is fed into the plasma flame most commonly via an external powder port mounted near the anode nozzle exit. The powder is so rapidly heated and accelerated that spray distances can be in the order of 25 to 150 mm.

    Fig. I Plasma Coating Schematic diagram

    A plasma torch is shown schematically in Figure. Gas, usually argon and/or nitrogen, with hydrogen or helium admixed in some cases, flows through a cylindrical copper anode which forms a constricting nozzle. A direct current arc is maintained between an axially placed tungsten cathode and the outer or expanding portion of the anode. Gas plasma (ionized gas) is generated with a core temperature of about 50,000°F (30,000°C). Powder, with a particle size ranging up to about 100 microns, is fed into the plasma stream in a variety of ways and locations. The powder is heated and accelerated by the plasma stream, usually to temperatures above its melting point, and to velocities ranging from 400 to almost 2,000 ft/sec. The actual powder temperature distribution and velocity are strongly a function of the torch design. The gases chosen for

    plasma do not usually react significantly with the powder particles; however, reaction with the external environment, normally air, may lead to significant changes in the coating. The most significant reaction with metallic and carbide coatings is oxidation. The unique design of raxair Surface Technologies torches results in less oxidation than occurs with most other plasma torches. To reduce degradation during deposition even further, coatings may be produced using either an inert gas shield surrounding the effluent or by spraying in a vacuum chamber under a low pressure of inert gas. Argon is usually used in both cases as the inert gas. A proprietary Praxair gas shroud is extremely efficient in inhibiting oxidation and is less costly than spraying in low pressure chambers. Plasma deposition is a line-of-sight process. However, because of the relatively small size of the torch, the inside surface of hollow cylinders (and some other more complex shapes) can frequently be coated with appropriate traversing equipment. Torches have been produced which can coat inside cylinders to substantial depths. The as-deposited surface roughness of Praxair plasma coatings vary with the type of coating from about 60 to over 300 micro inches Ra. Although for many applications the coating is used as deposited, some are ground or ground and lapped to 1 to 10 micro inches, Ra. Typical coating thicknesses range from about 0.002 to 0.020 inch, but both thicker and thinner coatings are used on occasion.

    Fig. II Plasma Spray Coating Schematic diagram

    SLURRY EROSIVE WEAR

    SLURRY can be described as a mixture of solid particles in a liquid (usually water) of such a consistency that it can be readily pumped. The term slurry erosion is strictly defined as that type of wear, or loss of mass, that is experienced by a material exposed to a high-velocity stream of slurry. This erosion occurs either when the material moves at a certain velocity through the slurry or when the slurry moves past the material at a certain velocity. Typical pump able slurries possess inherent apparent abrasivity, which must be determined by testing to enable cost predictions for pump replacement parts or other equipment used for slurries. Material in certain slurry does not indicate how that material would respond to another slurry. Slurry is a mixture of solids and liquids. Its physical characteristics are dependent on many factors such as size and distribution of particles, concentration of solids in the liquid phase, size of the conduit, level of turbulence, temperature, and absolute (or dynamic) viscosity of the carrier. Nature offers examples of slurry flows such as seasonal floods that carry silt and gravel. A slurry mixture is a mixture of a carrying fluid and solid particles held in suspension. The most commonly used fluid is water, however in some cases air is also used such as in pneumatic conveying.

    INCONEL 718

    INCONEL 718 is a precipitation-hardenable nickel- chromium alloy also containing significant amounts of iron, niobium, and molybdenum along with lesser amounts of aluminum and titanium. It combines corrosion resistance and high strength with out-standing weldability including resistance to post-weld cracking. The alloy has excellent creep-rupture strength at temperatures to 1300°F (700°C).Used in gas turbines, rocket motors, spacecraft, nuclear reactors, pumps, and tooling. INCONEL alloy 718SPF is a special version of INCONEL alloy 718, designed for super plastic forming.

    The compositions and various other properties of INCONEL 718 is as given below

    INCONEL 718 Chemical composition

    Alloy

    %

    Ni

    Cr

    Fe

    Mo

    Nb

    Co

    C

    Mn

    Si

    S

    Cu

    Al

    Ti

    718

    Min.

    50

    17

    balance

    2.8

    4.75

    0.2

    0.7

    Max.

    55

    21

    3.3

    5.5

    1

    0.08

    0.35

    0.35

    0.01

    0.3

    0.8

    1.15

    INCONEL 718 Physical properties

    Density

    8.2 g/cm³

    Melting point

    1260-1340

    INCONEL 718 Alloy minimum mechanical properties in the room temperature

    Alloy

    Tensile strength Rm N/mm²

    Yield strength R P0. 2N/mm²

    Elongation A 5 %

    Brinell hardness HB

    Solution treatment

    965

    550

    30

    363

    INCONEL 718 characteristics are as below:

    • Workability

    • High tensile strength, endurance strength, creep strength, and rupture strength at 700*C

    • Steady mechanical performance at low temperature

    • Good welding performance

      INCONEL 718 metallurgical structure

      INCONEL 718 alloy is Austenitic structure, precipitation hardening generate "" made it excellent mechanical performance. Grain boundary generate "" made it the best plasticity in the heat treatment.

      INCONEL 718 corrosion resistance

      718 alloy with extremely resistance to stress corrosion cracking and pitting ability in high temperature or low temperature environments, especially the inoxidability in the high temperature

      INCONEL 718 application field

      The elevated temperature strength, excellent corrosion resistance and workability at 700*C properties made it to be used in a wide range applications

      Steam turbine Liquid fuel rocket

      Cryogenic engineering Acid environment Nuclear engineering

  4. EXPERIMENTAL DETAILS

    Base metal : COPPER Coating material: INCONEL718 Stage 1

    Preparation of specimen by firstly cutting, then subsequently by milling, drilling and then finishing by filing process in workshop.

    Stage 2

    Specimens are prepared to size to the following sizes Flat specimen: 25mm*25mm*10mm

    Stage 3

    The coating material was plasma sprayed on to the base metal to a thickness of 100µm at Spray met Coatings Industries Pvt. ltd.

    Specification of plasma spray coatings VOLTAGE 60-70V

    CURRENT 495amps INNERT GASES

    Primary gas HYDROGEN (flow rate-100m3/min) Secondary gas ARGON (flow rate -100m3/min)

    TIO2 POWDER 100gm/min SPECIMEN PREPARATION

    • Cleaning with Trichloroethylene

    • 24 mesh Al2O3 grit blasting COATING

      Bond coating – Ni, Cr

      Coating thickness INCONEL718 (100-120microns)

      DISTANCE OF SPRAY GUN FROM SPECIMEN 6

      inches

      Stage 4

      Before the start of the actual test, initial weights of the coated and uncoated specimen are found. Details of the following tests were collected

    • Slurry erosive wear test

    • Test parameters

    1. Effect of slurry concentration

    2. Effect of particle size

    3. Effect of speed

    Stage 5

    During each test the specimens will be held in the holder of the slurry erosive machine and will be made to run in the slurry concentration by varying the parameters.

    Stage 6

    After each test the specimens will be cleaned in water, dried, washed with acetone solution and their final weights will be tabulated and results will be tabulated and graphs will be plotted.

    Overall Mass Loss (g):

    Coated Specimen – 0.0078 Uncoated Specimen -0.0088

    Time (min)

    Speed (rpm)

    Grain Size (µ)

    Sand Co ncen- tratio n

    Co ated Specimen M asses (grams)

    Unco ated Specimen M asses (grams)

    Initial

    Final

    M ass lo ss

    Initial

    Final

    M ass Lo ss

    0

    1000

    425

    100

    41.5223

    39.579

    30

    1000

    425

    100

    41.522

    41.5189

    0.0034

    39.58

    39.576

    0.003

    60

    1000

    425

    100

    41.519

    41.5182

    0.0007

    39.58

    39.5756

    0.0004

    90

    1000

    425

    100

    41.518

    41.5179

    0.0003

    39.58

    39.5748

    0.0008

    120

    1000

    425

    100

    41.518

    41.5173

    0.0006

    39.57

    39.574

    0.0008

    150

    1000

    425

    100

    41.517

    41.5168

    0.0005

    39.57

    39.5733

    0.0007

    180

    1000

    425

    100

    41.517

    41.5165

    0.0003

    39.57

    39.5732

    0.0001

    210

    1000

    425

    100

    41.517

    41.5161

    0.0004

    39.57

    39.5724

    0.0008

    240

    1000

    425

    100

    41.516

    41.5158

    0.0003

    39.57

    39.5717

    0.0007

    270

    1000

    425

    100

    41.516

    41.5152

    0.0006

    39.57

    39.5708

    0.0009

    300

    1000

    425

    100

    41.515

    41.5148

    0.0004

    39.57

    39.5701

    0.0007

    Time (min)

    Speed (rpm)

    Grain Size (µ)

    Sand Co ncen- tratio n

    Co ated Specimen M asses (grams)

    Unco ated Specimen M asses (grams)

    Initial

    Final

    M ass lo ss

    Initial

    Final

    M ass Lo ss

    0

    1000

    425

    100

    41.5223

    39.579

    30

    1000

    425

    100

    41.522

    41.5189

    0.0034

    39.58

    39.576

    0.003

    60

    1000

    425

    100

    41.519

    41.5182

    0.0007

    39.58

    39.5756

    0.0004

    90

    1000

    425

    100

    41.518

    41.5179

    0.0003

    39.58

    39.5748

    0.0008

    120

    1000

    425

    100

    41.518

    41.5173

    0.0006

    39.57

    39.574

    0.0008

    150

    1000

    425

    100

    41.517

    41.5168

    0.0005

    39.57

    39.5733

    0.0007

    180

    1000

    425

    100

    41.517

    41.5165

    0.0003

    39.57

    39.5732

    0.0001

    210

    1000

    425

    100

    41.517

    41.5161

    0.0004

    39.57

    39.5724

    0.0008

    240

    1000

    425

    100

    41.516

    41.5158

    0.0003

    39.57

    39.5717

    0.0007

    270

    1000

    425

    100

    41.516

    41.5152

    0.0006

    39.57

    39.5708

    0.0009

    300

    1000

    425

    100

    41.515

    41.5148

    0.0004

    39.57

    39.5701

    0.0007

    TABLE II: Effect of Particle Size on Coated Specimen and Uncoated Specimen for grain size of 425µ

    Fig. III: Slurry erosive wear setup.

  5. RESULTS AND DISCUSSIONS

    MEASUREMENT OF WEAR RATE USING SLURRY EROSION TESTER

    EFFECT OF PARTICLE SIZE

    TABLE I: Effect of Particle Size on Coated Specimen and Uncoated Specimen for grain size of 212µ

    0.002

    Mass lossin grams

    Mass lossin grams

    0.0015

    0.001

    0.0005

    0

    0.004

    0.0035

    0.003

    Mass loss(g)

    Mass loss(g)

    0.0025

    0.002

    0.0015

    0.001

    0.0005

    0

    Co a

    30

    120

    210

    300

    30

    120

    210

    300

    Time in minutes

    30

    120

    210

    300

    30

    120

    210

    300

    Time in minutes

    Coated Uncoated

    41.9315

    Time (min)

    Speed (rpm)

    Grain Size (µ)

    Sand Co ncen- tratio n

    Co ated Specimen M asses (grams)

    Unco ated Specimen M asses (grams)

    Initial

    Final

    M ass lo ss

    Initial

    Final

    M ass lo ss

    0

    1000

    212

    100

    41.9371

    41.0363

    30

    1000

    212

    100

    41.9371

    41.9355

    0.0016

    41.0363

    41.0355

    0.0008

    60

    1000

    212

    100

    41.9355

    41.9349

    0.0006

    41.0355

    41.0346

    0.0009

    90

    1000

    212

    100

    41.9349

    41.9345

    0.0004

    41.0346

    41.0337

    0.0009

    120

    1000

    212

    100

    41.9345

    41.9338

    0.0007

    41.0337

    41.0325

    0.0012

    150

    1000

    212

    100

    41.9338

    41.9332

    0.0006

    41.0325

    41.0308

    0.0017

    180

    1000

    212

    100

    41.9332

    41.9325

    0.0007

    41.0308

    41.0302

    0.0006

    210

    1000

    212

    100

    41.9325

    0.001

    41.0302

    41.0295

    0.0007

    240

    1000

    212

    100

    41.9315

    41.9303

    0.0012

    41.0295

    41.029

    0.0005

    270

    1000

    212

    100

    41.9303

    41.9298

    0.0005

    41.029

    41.0279

    0.0011

    300

    1000

    212

    100

    41.9298

    41.9293

    0.0005

    41.0279

    41.0275

    0.0004

    Time (min)

    Speed (rpm)

    Grain Size (µ)

    Sand Co ncen- tratio n

    Co ated Specimen M asses (grams)

    Unco ated Specimen M asses (grams)

    Initial

    Final

    M ass lo ss

    Initial

    Final

    M ass lo ss

    0

    1000

    212

    100

    41.9371

    41.0363

    30

    1000

    212

    100

    41.9371

    41.9355

    0.0016

    41.0363

    41.0355

    0.0008

    60

    1000

    212

    100

    41.9355

    41.9349

    0.0006

    41.0355

    41.0346

    0.0009

    90

    1000

    212

    100

    41.9349

    41.9345

    0.0004

    41.0346

    41.0337

    0.0009

    120

    1000

    212

    100

    41.9345

    41.9338

    0.0007

    41.0337

    41.0325

    0.0012

    150

    1000

    212

    100

    41.9338

    41.9332

    0.0006

    41.0325

    41.0308

    0.0017

    180

    1000

    212

    100

    41.9332

    41.9325

    0.0007

    41.0308

    41.0302

    0.0006

    210

    1000

    212

    100

    41.9325

    41.9315

    0.001

    41.0302

    41.0295

    0.0007

    240

    1000

    212

    100

    41.9315

    41.9303

    0.0012

    41.0295

    41.029

    0.0005

    270

    1000

    212

    100

    41.9303

    41.9298

    0.0005

    41.029

    41.0279

    0.0011

    300

    1000

    212

    100

    41.9298

    41.9293

    0.0005

    41.0279

    41.0275

    0.0004

    Overall Mass Loss (g):

    Coated Specimen – 0.0079

    Uncoated Specimen – 0.0089

    TABLE III: Effect of Particle Size on Coated Specimen and Uncoated Specimen for grain size of 600µ

    EFFECT OF SAND CONCENTRATION

    TABLE IV: Effect of Sand Concentration on Coated Specimen and on Uncoated Specimen for concentration of 50 g/l

    Time (min)

    Speed (rpm)

    Grain Size (µ)

    Sand Co ncen- tratio n

    Co ated Specimen M asses (grams)

    Unco ated Specimen M asses (grams)

    Initial

    Final

    M ass lo ss

    Initial

    Final

    M ass lo ss

    0

    1000

    600

    100

    41.6561

    52.0257

    30

    1000

    600

    100

    41.656

    41.6538

    0.0023

    52.0257

    52.0236

    0.0021

    60

    1000

    600

    100

    41.654

    41.6513

    0.0025

    52.0236

    52.0222

    0.0014

    90

    1000

    600

    100

    41.651

    41.6508

    0.0005

    52.0222

    52.0218

    0.0004

    120

    1000

    600

    100

    41.651

    41.649

    0.0018

    52.0218

    52.0213

    0.0005

    150

    1000

    600

    100

    41.649

    41.6488

    0.0002

    52.0213

    52.0204

    0.0009

    180

    1000

    600

    100

    41.649

    41.6484

    0.0004

    52.0204

    52.0195

    0.0009

    210

    1000

    600

    100

    41.648

    41.648

    0.0004

    52.0195

    52.018

    0.0015

    240

    1000

    600

    100

    41.648

    41.6473

    0.0007

    52.018

    52.0175

    0.0005

    270

    1000

    600

    100

    41.647

    41.6469

    0.0004

    52.0175

    52.0164

    0.0011

    300

    1000

    600

    100

    41.647

    41.6464

    0.0005

    52.0164

    52.0157

    0.0007

    0.003

    0.0025 Co

    Mass loss

    Mass loss

    0.002 a

    0.0015

    0.001

    0.0005

    30

    120

    210

    300

    30

    120

    210

    300

    0

    50

    Time (min)

    Speed (rpm)

    Grain Size (µ)

    Sand Co ncen- tratio n

    Co ated Specimen M asses (grams)

    Unco ated Specimen M asses (grams)

    Initial

    Final

    M ass lo ss

    Initial

    Final

    M ass lo ss

    0

    1000

    425

    50

    41.368

    52.0385

    30

    1000

    425

    50

    41.37

    41.367

    0.0005

    52.04

    52.0376

    0.0009

    60

    1000

    425

    50

    41.37

    41.366

    0.0007

    52.04

    52.0369

    0.0007

    90

    1000

    425

    41.37

    41.366

    0.0005

    52.04

    52.0362

    0.0007

    120

    1000

    425

    50

    41.37

    41.365

    0.0008

    52.04

    52.0357

    0.0005

    150

    1000

    425

    50

    41.37

    41.364

    0.0009

    52.04

    52.0349

    0.0008

    180

    1000

    425

    50

    41.36

    41.364

    0.0006

    52.03

    52.0343

    0.0006

    210

    1000

    425

    50

    41.36

    41.363

    0.0008

    52.03

    52.0335

    0.0008

    240

    1000

    425

    50

    41.36

    41.362

    0.0006

    52.03

    52.0327

    0.0008

    270

    1000

    425

    50

    41.36

    41.362

    0.0006

    52.03

    52.0312

    0.0015

    300

    1000

    425

    50

    41.36

    41.36

    0.0012

    52.03

    52.0301

    0.0011

    Time (min)

    Speed (rpm)

    Grain Size (µ)

    Sand Co ncen- tratio n

    Co ated Specimen M asses (grams)

    Unco ated Specimen M asses (grams)

    Initial

    Final

    M ass lo ss

    Initial

    Final

    M ass lo ss

    0

    1000

    425

    50

    41.368

    52.0385

    30

    1000

    425

    50

    41.37

    41.367

    0.0005

    52.04

    52.0376

    0.0009

    60

    1000

    425

    50

    41.37

    41.366

    0.0007

    52.04

    52.0369

    0.0007

    90

    1000

    425

    50

    41.37

    41.366

    0.0005

    52.04

    52.0362

    0.0007

    120

    1000

    425

    50

    41.37

    41.365

    0.0008

    52.04

    52.0357

    0.0005

    150

    1000

    425

    50

    41.37

    41.364

    0.0009

    52.04

    52.0349

    0.0008

    180

    1000

    425

    50

    41.36

    41.364

    0.0006

    52.03

    52.0343

    0.0006

    210

    1000

    425

    50

    41.36

    41.363

    0.0008

    52.03

    52.0335

    0.0008

    240

    1000

    425

    50

    41.36

    41.362

    0.0006

    52.03

    52.0327

    0.0008

    270

    1000

    425

    50

    41.36

    41.362

    0.0006

    52.03

    52.0312

    0.0015

    300

    1000

    425

    50

    41.36

    41.36

    0.0012

    52.03

    52.0301

    0.0011

    0.0016

    Mass Loss in grams

    Mass Loss in grams

    0.0014

    0.0012

    0.001

    0.0008

    0.0006

    0.0004

    0.0002

    0

    Coated Uncoated

    30

    90

    150

    210

    270

    30

    90

    150

    210

    270

    Time in minutes

    Time in minutes

    Overall Mass Loss (g):

    Coated Specimen – 0.0097

    Uncoated Specimen – 0.010

    EFFECT OF PARTICLE SIZE

    From the above graph we can conclude that as size of the sand particle increases wear rate of the specimen also increases but when compared to the coated specimen, uncoated specimen wears out more.

    Overall Mass Loss (g):

    Coated Specimen – 0.0072

    Uncoated Specimen – 0.0084

    TABLE V: Effect of Sand Concentration on Coated Specimen and on Uncoated Specimen for concentration of 100 g/l

    TABLE VI: Effect of Sand Concentration on Coated Specimen and on Uncoated Specimen for concentration of 150 g/l

    Time (min)

    Speed (rpm)

    Grain Size (µ)

    Sand Co ncen- tratio n

    Co ated Specimen M asses (grams)

    Unco ated Specimen M asses (grams)

    Initial

    Final

    M ass lo ss

    Initial

    Final

    M ass lo ss

    0

    1000

    425

    150

    41.522

    51.0253

    30

    1000

    425

    150

    41.52

    41.519

    0.0034

    51.03

    51.0237

    0.0016

    60

    1000

    425

    150

    41.52

    41.518

    0.0007

    51.02

    51.0225

    0.0012

    90

    1000

    425

    150

    41.52

    41.518

    0.0003

    51.02

    51.0217

    0.0008

    120

    1000

    425

    150

    41.52

    41.517

    0.0006

    51.02

    51.0209

    0.0008

    150

    1000

    425

    150

    41.52

    41.517

    0.0005

    51.02

    51.0202

    0.0007

    180

    1000

    425

    150

    41.52

    41.517

    0.0003

    51.02

    51.0196

    0.0006

    210

    1000

    425

    150

    41.52

    41.516

    0.0004

    51.02

    51.0189

    0.0007

    240

    1000

    425

    150

    41.52

    41.516

    0.0003

    51.02

    51.0175

    0.0014

    270

    1000

    425

    150

    41.52

    41.515

    0.0006

    51.02

    51.0163

    0.0012

    300

    1000

    425

    150

    41.52

    41.515

    0.0004

    51.02

    51.0152

    0.0011

    Time (min)

    Speed (rpm)

    Grain Size (µ)

    Sand Co ncen- tratio n

    Co ated Specimen M asses (grams)

    Unco ated Specimen M asses (grams)

    Initial

    Final

    ass lo ss

    Initial

    Final

    M ass Lo ss

    0

    1000

    425

    100

    41.522

    39.579

    30

    1000

    425

    100

    41.52

    41.519

    0.0034

    39.58

    39.576

    0.003

    60

    1000

    425

    100

    41.52

    41.518

    0.0007

    39.58

    39.576

    0.0004

    90

    1000

    425

    100

    41.52

    41.518

    0.0003

    39.58

    39.575

    0.0008

    120

    1000

    425

    100

    41.52

    41.517

    0.0006

    39.57

    39.574

    0.0008

    150

    1000

    425

    100

    41.52

    41.517

    0.0005

    39.57

    39.573

    0.0007

    180

    1000

    425

    100

    41.52

    41.517

    0.0003

    39.57

    39.573

    0.0001

    210

    1000

    425

    100

    41.52

    41.516

    0.0004

    39.57

    39.572

    0.0008

    240

    1000

    425

    100

    41.52

    41.516

    0.0003

    39.57

    39.572

    0.0007

    270

    1000

    425

    100

    41.52

    41.515

    0.0006

    39.57

    39.571

    0.0009

    300

    1000

    425

    100

    41.52

    41.515

    0.0004

    39.57

    39.57

    0.0007

    Time (min)

    Speed (rpm)

    Grain Size (µ)

    Sand Co ncen- tratio n

    Co ated Specimen M asses (grams)

    Unco ated Specimen M asses (grams)

    Initial

    Final

    ass lo ss

    Initial

    Final

    M ass Lo ss

    0

    1000

    425

    100

    41.522

    39.579

    30

    1000

    425

    100

    41.52

    41.519

    0.0034

    39.58

    39.576

    0.003

    60

    1000

    425

    100

    41.52

    41.518

    0.0007

    39.58

    39.576

    0.0004

    90

    1000

    425

    100

    41.52

    41.518

    0.0003

    39.58

    39.575

    0.0008

    120

    1000

    425

    100

    41.52

    41.517

    0.0006

    39.57

    39.574

    0.0008

    150

    1000

    425

    100

    41.52

    41.517

    0.0005

    39.57

    39.573

    0.0007

    180

    1000

    425

    100

    41.52

    41.517

    0.0003

    39.57

    39.573

    0.0001

    210

    1000

    425

    100

    41.52

    41.516

    0.0004

    39.57

    39.572

    0.0008

    240

    1000

    425

    100

    41.52

    41.516

    0.0003

    39.57

    39.572

    0.0007

    270

    1000

    425

    100

    41.52

    41.515

    0.0006

    39.57

    39.571

    0.0009

    300

    1000

    425

    100

    41.52

    41.515

    0.0004

    39.57

    39.57

    0.0007

    0.004

    0.0035

    Mass loss(g)

    Mass loss(g)

    0.003

    0.0025

    0.002

    0.0015

    0.001

    0.0005

    0

    Coated Uncoated

    0.004

    Mass loss in grams

    Mass loss in grams

    0.003

    0.002

    0.001

    0

    30 90 150 210 270

    Time in minutes

    Coated Uncoated

    30

    90

    150

    210

    270

    30

    90

    150

    210

    270

    Time in minutes

    Overall Mass Loss (g):

    Coated Specimen – 0.0075

    Overall Mass Loss (g):

    Coated Specimen – 0.0079

    Uncoated Specimen – 0.0101

    EFFECT OF SLURRY CONCENTRATION

    From the above graph we can conclude that as the co t , r

    ncentration of the sand in he water increases wea rate of

    Uncoated Specimen – 0.0089

    the specimen also increases because more sand grains hit against the surface and the wear of the specimen increases but when compared to the coated specimen, uncoated specimen wears out more.

    EFFECT OF SPEED

    TABLE VII: Effect of Speed on Coated Specimen and on Uncoated Specimen for speed of 500 rpm

    0.008

    Mass Loss in grams

    Mass Loss in grams

    0.007

    0.006

    0.005

    0.004

    0.003

    0.002

    0.001

    0

    30 60 90T1im20e1i5n0m18in0u21te0s240270300

    0.004

    Mass loss in grams

    Mass loss in grams

    0.0035

    0.003

    0.0025

    0.002

    0.0015

    0.001

    0.0005

    0

    30 90 150210270

    Time in minutes

    Coated Uncoated

    Overall Mass Loss (g):

    Coated Specimen – 0.0073

    Uncoated Specimen – 0.0084

    TABLE VIII: Effect of Speed on Coated Specimen and on Uncoated Specimen for speed of 1000 rpm

    Overall Mass Loss (g):

    Coated Specimen – 0.0075 Uncoated Specimen – 0.0089

    TABLE IX: Effect of Speed on Coated Specimen and on Uncoated Specimen for speed of 1500 rpm

    Time (min)

    Spee d (rpm)

    Grain Size (µ)

    Sand Co ncen- tratio n

    Co ated Specimen M asses (grams)

    Unco ated Specimen M asses (grams)

    Initial

    Final

    M ass lo ss

    Initial

    Final

    M ass lo ss

    0

    1000

    425

    150

    41.5223

    51.0253

    30

    1000

    425

    150

    41.52

    41.5189

    0.0034

    51.03

    51.0237

    0.0016

    60

    1000

    425

    150

    41.52

    41.5182

    0.0007

    51.02

    51.0225

    0.0012

    90

    1000

    425

    150

    41.52

    41.5179

    0.0003

    51.02

    51.0217

    0.0008

    120

    1000

    425

    150

    41.52

    41.5173

    0.0006

    51.02

    51.0209

    0.0008

    150

    1000

    425

    150

    41.52

    41.5168

    0.0005

    51.02

    51.0202

    0.0007

    180

    1000

    425

    150

    41.52

    41.5165

    0.0003

    51.02

    51.0196

    0.0006

    210

    1000

    425

    150

    41.52

    41.5161

    0.0004

    51.02

    51.0189

    0.0007

    240

    1000

    425

    150

    41.52

    41.5158

    0.0003

    51.02

    51.0175

    0.0014

    270

    1000

    425

    150

    41.52

    41.5152

    0.0006

    51.02

    51.0163

    0.0012

    300

    1000

    425

    150

    41.52

    41.5148

    0.0004

    51.02

    51.0152

    0.0011

    Time (min)

    Speed (rpm)

    Grain Size (µ)

    Sand Co ncen- tratio n

    Co ated Specimen M asses (grams)

    Unco ated Specimen M asses (grams)

    Initial

    Final

    M ass lo ss

    Initial

    Final

    M ass lo ss

    0

    1500

    425

    100

    41.517

    52.0257

    30

    1500

    425

    100

    41.52

    41.512

    0.0048

    52.026

    52.0224

    0.0033

    60

    1500

    425

    100

    41.51

    41.511

    0.0007

    52.022

    52.0214

    0.001

    90

    1500

    425

    100

    41.51

    41.511

    0.0004

    52.021

    52.0204

    0.001

    120

    1500

    425

    100

    41.51

    41.51

    0.0005

    52.02

    52.0197

    0.0007

    150

    1500

    425

    100

    41.51

    41.51

    0.0006

    52.02

    52.0189

    0.0008

    180

    1500

    425

    100

    41.51

    41.509

    0.0006

    52.019

    52.018

    0.0009

    210

    1500

    425

    100

    41.51

    41.509

    0.0007

    52.018

    52.0172

    0.0008

    240

    1500

    425

    100

    41.51

    41.508

    0.0005

    52.017

    52.0161

    0.0011

    270

    1500

    425

    100

    41.51

    41.507

    0.0008

    52.016

    52.0152

    0.0009

    300

    1500

    425

    100

    41.51

    41.507

    0.0006

    52.015

    52.014

    0.0012

    Time (min)

    Spee d (rpm)

    Grain Size (µ)

    Sand Co ncen- tratio n

    Co ated Specimen M asses (grams)

    Unco ated Specimen M asses (grams)

    Initial

    Final

    M ass lo ss

    Initial

    Final

    M ass lo ss

    0

    1000

    425

    150

    41.5223

    51.0253

    30

    1000

    425

    150

    41.52

    41.5189

    0.0034

    51.03

    51.0237

    0.0016

    60

    1000

    425

    150

    41.52

    41.5182

    0.0007

    51.02

    51.0225

    0.0012

    90

    1000

    425

    150

    41.52

    41.5179

    0.0003

    51.02

    51.0217

    0.0008

    120

    1000

    425

    150

    41.52

    41.5173

    0.0006

    51.02

    51.0209

    0.0008

    150

    1000

    425

    150

    41.52

    41.5168

    0.0005

    51.02

    51.0202

    0.0007

    180

    1000

    425

    150

    41.52

    41.5165

    0.0003

    51.02

    51.0196

    0.0006

    210

    1000

    425

    150

    41.52

    41.5161

    0.0004

    51.02

    51.0189

    0.0007

    240

    1000

    425

    150

    41.52

    41.5158

    0.0003

    51.02

    51.0175

    0.0014

    270

    1000

    425

    150

    41.52

    41.5152

    0.0006

    51.02

    51.0163

    0.0012

    300

    1000

    425

    150

    41.52

    41.5148

    0.0004

    51.02

    51.0152

    0.0011

    Time (min)

    Speed (rpm)

    Grain Size (µ)

    Sand Co ncen- tratio n

    Co ated Specimen M asses (grams)

    Unco ated Specimen M asses (grams)

    Initial

    Final

    M ass lo ss

    Initial

    Final

    M ass lo ss

    0

    1500

    425

    100

    41.517

    52.0257

    30

    1500

    425

    100

    41.52

    41.512

    0.0048

    52.026

    52.0224

    0.0033

    60

    1500

    425

    100

    41.51

    41.511

    0.0007

    52.022

    52.0214

    0.001

    90

    1500

    425

    100

    41.51

    41.511

    0.0004

    52.021

    52.0204

    0.001

    120

    1500

    425

    100

    41.51

    41.51

    0.0005

    52.02

    52.0197

    0.0007

    150

    1500

    425

    100

    41.51

    41.51

    0.0006

    52.02

    52.0189

    0.0008

    180

    1500

    425

    100

    41.51

    41.509

    0.0006

    52.019

    52.018

    0.0009

    210

    1500

    425

    100

    41.51

    41.509

    0.0007

    52.018

    52.0172

    0.0008

    240

    1500

    425

    100

    41.51

    41.508

    0.0005

    52.017

    52.0161

    0.0011

    270

    1500

    425

    100

    41.51

    41.507

    0.0008

    52.016

    52.0152

    0.0009

    300

    1500

    425

    100

    41.51

    41.507

    0.0006

    52.015

    52.014

    0.0012

    0.006

    Mass loss in grams

    Mass loss in grams

    0.005

    0.004

    0.003

    0.002

    0.001

    0

    30

    90

    150

    210

    270

    30

    90

    150

    210

    270

    Time in minutes

    Coated Uncoated

    1. With increase in sand concentration, wear rate of test specimen increases.

    2. With increase in speed, wear rate of test specimen increases.

    3. On the basis of comparison between the results obtained of both uncoated and coated specimens, it is clear that coating increases the wear resisting property of the base metal.

    ACKNOWLEDGMENT

    I am very pleased to present this paper titled TO STUDY THE EFFECTS OF COATING ON SLURRY-EROSIVE WEAR OF INCONEL718 ON COPPER.

    I express my sincere thanks to Mr. Harish Kumar N S,

    Overall Mass Loss (g):

    Coated Specimen – 0.0102

    Uncoated Specimen – 0.0117

    EFFECT OF SPEED

    From the above graphs, we can conclude that as the speed of rotation increases, more no. of sand particles hits the specimen hence the wear of the specimen increases but when compared to the coated specimen uncoated specimen wears out more.

  6. CONCLUSIONS

Based on the tests carried out to study the effect of wear of INCONEL 718 coated on copper as explained in the previous chapter and within the scope this investigation, the following conclusions have been drawn.

  1. Plasma spray coating of INCONEL 718 on copper is effectively done for required thickness.

  2. With increase in sand grain size, wear rate of test specimen increases.

Asst. Professor, and Dept. of Mechanical Engineering.

This paper would not have been possible without the authors, whose books and papers we have referred while preparing the paper. We whole-heartedly thank the authorities of college library for providing excellent facilities.

REFERENCES

  1. Abel Andre C. Recco, Diana Lopez, Andre F. Bevilacqua, Felipe da Silva,Andre P. Tschiptschin, Improvement of the slurry erosion resistance of an austenitic stainless teel with combinations of surface treatments:Nitriding and TiN coating , SurfaceCoatingsTechnology202(2007)993997.

  2. Chang-Jiu Li , Guan-Jun Yanga, Akira Ohmori, Relationship between particle erosion and lamellar microstructure for plasma-sprayed alumina coatings, Wear 260 (2006)11661172.

  3. D.Z.Guo, F.L.Li, J.Y.Wang, J.S.Sun, Effects of post-coating processing on structure and erosive wear characteristics of flame and plasma spray coatings, Surface & Coatings Technology 73 (1995) 7378.

  4. H.W. Hoppel , H. Mughrabi, H.-G. Sockel , S. Schmidt, G. Vetter , Hydroabrasive wear behaviour and damage mechanisms of different hard coatings, Wear 225229999,10881099.

  5. Huang Chen, Chuanxian Ding, Pingyu Zhang, Peiqing La, Soo Wohn Lee, Wear of plasma-sprayed nanostructured zirconia coatings against stainless steel under distilled-water conditions, Surface and Coatings Technology 173 (2003) 144149.

Leave a Reply

Your email address will not be published. Required fields are marked *