PROPERTIES OF POLYMER COMPOSITE MATERIALS. Prof. Zaffar Mohammad Khan, PhD.

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1 PROPERTIES OF POLYMER COMPOSITE MATERIALS Prof. Zaffar Mohammad Khan, PhD.

2 From Dedaulus to Vvyln

3 EVOLUTION OF COMPOSITES

4 COMPOSITES IN BARJ UL ARAB

5 COMPOSITE GROWTH RATE IN ENGINEERING INDUSTRIES

6 THE ALL COMPOSITE WORLD Any modern economy is built on the ability to exploit the opportunities on offer by new and existing high value markets such as composites Lord Mandelson

7 What are Composite Materials??? Composite materials are macroscopic combination of two or more materials complimenting each other such that resulting product has superior properties: 1.Matrix (Black) 2.Reinforcement Fibers (White) 3.Inter-phase STRONGER THAN STEEL YET LIGHTER THAN ALUMINIUM

8 Matrix Constituent Roles: Binds and holds reinforcement together Determines composite shape and geometry Transfers stresses to reinforcement Types: Ceramic (Temp < 6000 F) Metallic (Temp < 4000 F) Polymeric (Temp < 600 F) Determine Environmental resistance Shelf Life Compressive & transverse mechanical properties of composite Examples: Epoxy, Polyester, Vinyl ester, PEEK, Polycarbones

9 Reinforcement Constituent 1. Particulate: Good compression strength but poor tensile properties, and particles in cement. 2. Flakes: Effective solvent resistant but difficult fabrication. 3. Whiskers: High degree of strength but poor crack stopping properties. 4. Fibers: Better structural properties, crack stopping properties, flexibility of design requirement by changing orientation of fibers 0, +45, 90 Stacking sequence Examples: glass, carbon, kevlar & carbon fibers

10 Fiber Architecture

11 ADVANTAGES OF COMPOSITE MATERIALS Significant weight saving which increases payload and/or range along with fuel saving. Maximum specific strength and stiffness make them lighter than aluminum, stronger than steel. Permits aero-elastic tailoring of structural components. Flexibility of Design Integrated structures diminishes application of rivets. Enhanced fatigue life. Absence of corrosion. Reduced operational, manufacturing and maintenance cost. 11

12 12 Comparison of Composites with Metals

13 Aero-elastic Composite Structure Permits aero-elastic tailoring of structural components. The composite structure is tailored to meet varying aerodynamic requirements in aircrafts, cars and wind rotor blades. It reduces drag and enhances energy conservation.

14 Flexibility of Composite Design The mechanical properties of the composite structures could be optimized for tensile, shear or compression loadings through proper selection of fiber types, orientation and stacking sequence

15 Integrated Structure Integrated composite structure reduces rivets and associated weight which leads to integrated structure. Reduce operational, manufacturing and maintenance cost.

16 Influence of Vibrations on Composites The vibration damping characteristics of composites are far superior as compared to metals for following reasons; 1.Matrix visco-elastic effects and micro-cracking 2.Blunting of crack by in fibers transverse direction 3.Debonding and sliding of fibers in axial direction.

17 Manufacturing Methods and typical Applications Hand Lay-up Method: Ships, wind turbine blades, reinforcement to concrete bridge columns and slabs. Autoclave Method: Aircraft, space equipment, racing car Pultrusion Method: Rod, pipe Filament Winding Method: Rolls, pressure vessels, fly wheels, centrifugal separation Resin Injection Method: Aircraft components Prepreg Sheet Winding Method: Golf shaft, fishing rod Pressure Matched-Metal Die Method: Tennis racket, badminton racket Injection Method: General equipment

18 Autoclave Manufacturing

19 Structural Analysis

20 COMPOSITE DESIGN Cost & Weight Consideration Geometrical Envelop Manufacturing Processes Loading Spectra Environment Conceptual Design A creative function providing an Initial set of design drawings Trade Off Studies Cost/Weight Considerations Inspection Candidate Materials Modify Concept Acceptable Preliminary Design Defines materials and structural configuration, Manufacturing and tool plans, initial costs Detail Design & Evaluation Design and analysis of complete structure, Local details, design-to-cost evaluation, QA plans Development And Testing Modify Design Acceptable Detail Design Prototype Manufacture Modify (if required) Production Phase Updating cost/weight trade studies, Manufacturing Plans, tooling etc. 20

21 Aircraft and Automobiles

22 Composite Structures

23 Composites in Skiing and Cycling

24 Medical Industry The composite prosthesis is beneficial for people having physical disabilities. Applications include leg and foot prosthetics providing weight reduction of up to 68% compared to traditional metals such as stainless steel.

25 All Composite Car Body by Liquid Resin Infusion (Joint Venture of Academia-Industry Collaboration) Structural design and analysis using the Pro-E and ANSYS tools The pattern and mold was manufactured from carbon and glass /polyester composites. Resin impregnation through carbon fabric and curing using Resin Infusion Process. The car took part in Shell Eco Marathon Race in Malaysia and secured 26/ 120 position. Published in 42nd SAMPE Technical Conference Proceedings, Utah, USA [2].

26 Development of Windmill Turbine Blades Research Initiative by Academia, Industry & Research Center Wind Speed: 5-7 m/ sec. Air Density: 1.25 Kg/ m3 No of blades: 3 NACA Profile: Rotor Blade Diameter: 2.21 m Hub Height: 6-10 Design and Analysis at NUST. Vacuum bagging over mold having geometry at FiberTech. Structural testing at ACRC. SR NO Maximum Load (KG) Bending Stiffness KN/M Bending Stiffness Downward (KN/M) Bending Stiffness Average (KN/M) Applied load Upward KN Applied load Downward KN Maximum Displacement Upward mm Maximum Displacement Downward mm

27 Effect of Voids on Mechanical Properties of Carbon Epoxy Composite Materials Carbon-epoxy specimen were prepared by vacuum bagging, VARTM and RFI. Specimen were tested in tension, shear and flexural loading according to ASTM and correlated with degree of porosity. Porosities were observed in the test specimen and correlated to mechanical properties Stress ( MPa) S tr e s s (M P a ) TVBU TVIU 0.00 FVBU FVIU TVBU TVIU FVBU FVIU

28 Effect of Post cure on Mechanical Properties of Sandwich Composites The polystyrene foam, honeycomb, balsa wood cored sandwich having carbon fabric face sheets were cured/ post cured. Edgewise, flexural tests were conducted according to ASTM C364 & C393. Honeycomb structure demonstrated superior edgewise compression strength as compared to Styrofoam and Balsa wood. Post curing improved the compression strength of sandwich structure Tg Comparison Chart Edgew ise C om pressive stress(m Pa) Edgewise compressive strength of Honeycomb Core sandwich structures HC without Post cure HC with Post cure Edgewise Compressive stress of Styrofoam core sandwich structures T e m p e r a t u r e (C ) Edgew ise com pressive stress (M Pa) Poly Epoxy without PC Poly Epoxy with PC 0.00 SF without Post cure SF with Post cure

29 CONCLUSION Processing of composite materials may be taught. Campuses and R&D Center should be established to promote, composite science and technology. Advanced Composite promise to save upon energy needs in mass transportation by 5% and accelerated socio-economic development of engineering industries.

30 30 THANK YOU