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- 1. Composite material المؤ الموادوتصميم تحليل تلفه presented by D. Rasha Mohammed
- 7. Course content • 1.Introduction • 2.Classification of composite material • 3. Factors affecting the properties of composite material . • 4. Mechanics of composite material • 5. Failure of composite material • 6. Manufacturing of MMC,PMC and CMC • 7 Design of sandwich structure • 8. corrosion of material
- 8. Introduction A material systemcomposed of two or more physically distinct phases whose combination produces aggregate properties that are different from those of its constituents.
- 9. What is acomposite? A composite is a structural material which consists of combining two or more constituents Examples: Flesh in your leg reinforced with bones Concrete reinforced with steel Epoxy reinforced with graphite fibers.
- 10. Fibrous Composites • Generallythere are two phases – Matrix as a binder – Fiber as a reinforcement
- 11. Examples of NaturalComposites • Wood – Cellulose Fibers – Lignin Matrix • Bones – Collagen Fibers – Mineral Matrix
- 12. Historical Perspective • 4000B.C. Fibrous composites were used in Egypt in making laminated writing materials • 1300 BC: “You are no longer to supply the people with straw for making bricks; let them go and gather their own straw” - Exodus 5.7. • 1700 : French Scientist, Reumer talked about potential of glass fibers
- 13. Historical Perspectives (continued) •1939: Glass fiber manufactured commercially for high temperature electrical applications • 1950s: Boron and carbon fibers were produced to make ropes. • 1960s: Matrix added to make polymeric matrix composites
- 14. Historical Perspectives (continued) •1970s: Cold war forces development of metal matrix composites for military aircrafts and missile guidance systems • 1990s: High temperature ceramic matrix composites are being aggressively researched for use in next generation aircraft engines and power plant turbines
- 15. Why Composites areImportant • Composites can be very strong and stiff, yet very light in weight, so ratios of strength-to-weight and stiffness-to-weight are several times greater than steel or aluminum • High creep resistance • Fatigue properties are generally better than for common engineering metals • Toughness is often greater too • Composites can be designed that do not corrode like steel • Possible to achieve combinations of properties not attainable with metals, ceramics, or polymers alone
- 16. Disadvantages and Limitationsof Composite Materials • Properties of many important composites are anisotropic - the properties differ depending on the direction in which they are measured – this may be an advantage or a disadvantage. • Difficulty in fabrication. • Repair can be difficult. • Inspection and testing typically more complex. • Many of the polymer-based composites are subject to attack by chemicals or solvents, just as the polymers themselves are susceptible to attack. • Composite materials are generally expensive. • Manufacturing methods for shaping composite materials are often slow and costly.
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- 18. Where are composites used?????? CFRP– carbon fiber reinforced composite. GFRP – glass fiber reinforced composite
- 19. • Engineering applications – Aerospace – Automobile – Pressure vesseland pipes • Any place where high performance materials are desired Composites in industry Turret Shield Industrial Spring Medical Table Bullet proof shields www.composiflex.com
- 20. 20 Different Applications ofFRP composite Materials
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- 23. INTRODUCTION (contd.,) FRP Composites POLYMEMATRIX GLASS Fiber Reinforcement Polymer matrix Glass Carbon Aramid Epoxy Polyester Vinylester + 2/10/2023
- 24. Components in aComposite Material • Nearly all composite materials consist of two phases: –Primary phase - forms the matrix within which the secondary phase is embedded –Secondary phase - embedded phase sometimes referred to as a reinforcing phase, because it usually serves to strengthen the composite. – The reinforcing phase may be in the form of fibers, particles, or various other geometries .
- 25. Functions of theMatrix Material (Primary Phase) • Protect phases from environment. • Transfer Stresses to phases. • Holds the embedded phase in place, usually enclosing and often concealing it . • When a load is applied, the matrix shares the load with the secondary phase, in some cases deforming so that the stress is essentially born by the reinforcing agent .
- 26. Functions of theReinforced Material (Secondary Phase) ❖Secondary Phase (Reinforced material) provide key structural properties to the composite material. ❖The Reinforcing phase may be in the form of fibers, particles or flakes. ❖Ex: Plant fibers : Cotton, Jute, Hemp, sisal etc. ❖Animal fiber: Silk, wool etc. ❖Man made fibers : Glass, carbon , Kevlar, Graphite etc. All the natural fibers are Hydrophilic in nature ( Tendency to mix with water). But the matrix is polymeric are hydrophobic ( failing to mix with water) . This discrepancy leads to formation of ineffective interface. ❖ Fluctuating Mechanical Properties creates a problem of using natural fiber for plastic reinforcement.