Development of al-si-fe/sic Particulate Composites as Advanced Materials for Engineering Application

Development of al-si-fe/sic Particulate Composites as Advanced Materials for Engineering Application.

ABSTRACT

This work has been carried out to develop a particulate strengthened Al-Si-Fe composite using silicon carbide as the particulate. Al-Si-Fe alloy with 5-25 weight per cent silicon carbide particles was produced using the double stir casting method.

The composites were heat-treated at 500oC for 3hours and quenched in warm water at 65oC, aged at100, 200 and 300oC with various ageing times between 60 to 660 minutes.

The infrastructures of the various alloy particulate composites produced were examined. The physical and mechanical properties measured include densities, porosity, ageing kinetic, ultimate tensile strength, yield strength, hardness values and impact energy.

The result obtained reveals hardness values and activation energy of diffusion increased with an increase in the weight fraction of silicon carbide and accelerates the kinetic of ageing.

TABLE OF CONTENTS

TITLE PAGE———————————————————————i
DECLARATION—————————————————————–ii
CERTIFICATION————————————————————–iii
ACKNOWLEDGEMENT——————————————————–iv
ABSTRACT———————————————————————v

CHAPTER ONE

1.0 Introduction——————————————————————–1

CHAPTER TWO

2. 0 Literature Review————————————————————–6
2.1Aluminium Matrix composites (AMCS)—————————————6
2.2 Al-Si-Fe Alloy System———————————————————–7
2.3 Properties of Aluminium Matrix composites (AMCS) ———————–8
2.4 Types of Aluminium Matrix composites AMCs———————————10
2.4.1 Particle Reinforced Aluminium Matrix Composites (PMCs)—————–10
2.4.2 Short Fibre- And Whisker-Reinforced Aluminium Matrix Composites——-12 2.4.3
2.4.3 Continuous Fibre-Reinforced Aluminium Matrix Composites (CFAMCs)———-12
2.4.4 Monofilament Reinforced Aluminium Matrix Composites (MFAMCs)——-13
2.5 Primary processing of AMCs—————————————————–13
2.5.1 Liquid state processes————————————————————-13
2.5.2 Solid-state processes————————————————————16
2.6 Interfacial Characteristics of AMCs————————————————-18
2.6.1 Physical Phenomena at the Interface————————————–19
2.6.2 Chemical Reactions at the Interface—————————————-20
2.6.3 Metallurgy of the interfacial area—————————————–23
2.7 Properties of AMCs composites———————————————–25
2.7.1 Physical Properties of AMCs Composite————————————25
2.7.2 Mechanical properties of AMCs Composites——————————-28
2.7.3 Wear Resistance————————————————————–33
2.7.4 Corrosion Resistance———————————————————–34
2.8 Effect of ceramic reinforcements on the behaviour of aluminium matrix in
AMCs—35 2.8.1 Intrinsic Effects Ceramic Reinforcements————————–35
2.8.2 Extrinsic Effects of Ceramic Reinforcement—————————————-36
2.9 Thermal treatments of AMCs————————————————————-36
2.9.1 Age Hardening Characteristics of Ceramic Reinforced Aluminium Alloys—36
2.9.2 Principles of Age Hardening of Aluminium alloys/composites—————-40
2.9.3 Kinetic Analysis of Precipitation Reactions——————————————-41
2.10 Applications of AMCs————————————————————————-44

CHAPTER THREE

3.0 Materials and Methods————————————————————————-47
3.1 Materials—————————————————————————————-47
3.2 Equipment——————————————————————–47
3.3 Methods—————————————————————————47
3.3.1 Samples production———————————————————47
3.3.2 Heat treatment of the samples———————————————-49
3.3.3 Determination of Density—————————————————-49
3.3.4 Determination Apparent Porosity——————————————50
3.3.5 Hardness values determination———————————————50
3.3.6 Determination of the Tensile properties———————————–51
3.3.7 Impact Strength Determination———————————————51
3.3.8 Microstructural Examination———————————————–52

CHAPTER FOUR

4.0 Results and Discussion ———————————————————53
4.1 Physical Properties of Al-Si-Fe/Sic Composites————————————53
4.1.1 Macrostructural analysis———————————————————–53
4.1.2 Density——————————————————————————–53
4.1.3 Apparent Porosity——————————————————————-54
4.2 Kinetic characteristics of ageing—————————————————–55
4.2.1 Statistical analysis of the ageing process——————————————58
4.3 Microstructural analysis—————————————————————-62
4.4 Mechanical Properties of Al-Si-Fe/SiC Composites———————————63
4.4.1 Hardness Values———————————————————————–63
4.4.2 Yield and Tensile Strengths———————————————————–64
4.4.3 Percentage Elongation —————————————————————–67
4.4.4 Impact energy—————————————————————————-68

CHAPTER FIVE—————————————————————————–69

5.0 Conclusions and Recommendations—————————————————-69
5.1 Conclusions———————————————————————————69
5.2 Recommendations—————————————————————————72

REFERENCES ———————————————————————————–73

INTRODUCTION

In the two decades, most and development have aimed to monolithic metals and alloys with a phase with the primary purpose of enhancing their properties,

spanning the domains of physical, mechanical and fracture behaviour (Clyne, 2000, Surappa and Rohatgi, 1981), and strong interest has been shown in the application of metal matrix composites in the design of many engineering and non-engineering components (Maruyama, 1998, Jokinen and Rauta, 1992).

Potential uses of these materials in industries are numerous and they include such areas as aerospace (satellite struts), defense (electronic instrument racks), automotive (drive shafts and brake discs), sports goods (golf clubs and mountain bicycle frames), and marine (yacht fittings) (Clyne, 2000 and Ikechukwuka, 1997).

When compared with the unreinforced aluminium matrix alloy, MMCs, in general, have superior mechanical properties, such as high strength, high stiffness, high Wear resistance, and very good elevated temperature properties.

REFERENCES

Annual Books of ASTM Standards, (1990): Section 1. Iron and steel Products, volume 01 Pp 13 – 63
Asthana R (1998): Solidification processing of reinforced metals (Trans. Tech. Publ.) Pp 67-80.
Bayourni .M. Ribes .A, H. and Suéry .M (1988):”Aging Characteristics of SiC-Particle Reinforced AI-Si Alloys”, Proc. 9th. [email protected] Inter. Symp. on Metallurgy and Materials Science, [email protected] National Laboratory, Roskilde, Denmark, Pp 291- 296.
Christman .T, Needleman. A. Nutt .S. and Suresh .S (1989): “On Microstructural Evolution and Mechanical Modeling of Deformation of a Whisker-reinforced Metal-Matrix Composite”, Mater. Sci. Engr, Vol. A107, Pp 49-61.
Clyne T. W (ed.) (2000): Comprehensive composite material. Metal matrix Composites(ser. eds): Vol. 3, Pp 26-38.
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Dieter.G.E (1988): Mechanical Metallurgy, McGraw-Hill Company, Pp 184-223Donne.S, Krishnadev.M.R and Bouchard.R (1990): Metal and ceramic matrix mechanical behavior.

StudentsandScholarship Team.