Presentation is loading. Please wait.

Presentation is loading. Please wait.

DESIGN AND ANALYSIS OF A COMPRESSION MOLDED CARBON COMPOSITE WHEEL CENTER VINOTH KUMAR DHANANJAYAN Thesis Defense for MS Mechanical Engineering April 3,

Similar presentations


Presentation on theme: "DESIGN AND ANALYSIS OF A COMPRESSION MOLDED CARBON COMPOSITE WHEEL CENTER VINOTH KUMAR DHANANJAYAN Thesis Defense for MS Mechanical Engineering April 3,"— Presentation transcript:

1 DESIGN AND ANALYSIS OF A COMPRESSION MOLDED CARBON COMPOSITE WHEEL CENTER VINOTH KUMAR DHANANJAYAN Thesis Defense for MS Mechanical Engineering April 3, 2013 Committee : Prof. Robert Woods, University of Texas at Arlington (Advisor) Prof. Kent Lawrence, University of Texas at Arlington Prof. Wen Chan, University of Texas at Arlington 1

2 Background & Motivation Alternate process development of a high strength part Weight reduction Functional performance improvement Machining time reduction Cycle time – minutes Strength – equal to quasi isotropic Ref : Lambolab.com, composites world 2

3 Objective Study on factors influencing the compression molding process Analysis of existing and proposed design of a partRaw material selectionMold design Thermal system identification and analysis Process parameters Development of wheel center by compression molding process 3

4 Importance of closed mold and short fibers Directional properties High process time High skill requirement Intricate shapes not feasible High part cost Low volume Open mold continuous fiber Near isotropic properties Quicker cycle time in minutes Minimal skill dependency Near net shape part and ability to mold complex shapes Low part cost High volume Closed mold short fiber Advantageous closed mold process 4

5 Compression molding Minimal flow Less fiber breakage Ref : Duqueine, Mazumdar composites mfg, lamborghini urus 5

6 Compression molded parts Ref : Hexcel, Lamborghini, Audemars piguet, Carbon Forge, Duqueine, excel sports, DUC -helices 6

7 Process dependency COMPRESSION MOLDING resin type formability fiber content fillers Mold design Thermal system charge placement process temperature & pressure Press parallelism, mold finish, ejection Part strength volume Thickness variation Holes or mash off zones Moldability PART MATERIAL fiber length resin process parameters PROCESS Part Material Process 7

8 Wheel center part study Most suitable for compression molding – 20% improvement yields 1.58 lbs weight saving/car Improve lateral stiffness – high deformation High machining time and material wastage Lateral Load – Lateral load 750 lb – Normal reaction load 600 lb Braking Load – Braking load 600 lb – Normal reaction load 600 lb Ref : UTA FSAE team (load values) Reaction force due to weight Braking force Wheel center loads 8

9 Raw material selection Market study Hexcel, ten cate, Quantum composites 15 compounds Carbon epoxy and vinyl ester Benchmark properties – Al 6061 T6 9

10 Existing wheel center – lateral load FOS – 0.96 Deformation – ElementsEquiv Stress (ksi)Change % % % % 10

11 Existing wheel center – Braking load Deformation –

12 Inference Functional issue – Increase lateral stiffness – Strengthen riveting points Moldability – Provide drafts – Minimize pattern holes – Gradual thickness variation L 12

13 Proposed design Other designs studied 13 Proposed Existing

14 Proposed design – Lateral load >25 % Improvement 14 FOS – 1.48 FOS Stress

15 Proposed design – Braking load 15

16 Results comparison 16

17 Mold design Mold material - Al 6061 T6 – Better machinability – Quick heat transfer – Better surface finish Shear edge design – Complete filling – Escape of air Mold size – Length 15 – Breadth 14 – Thickness 2.5 Good mold design Better part quality 17

18 Heating system 18 Cartridge heaters Quantity – 4/mold Capacity – 450W Wattage required for heating the mold in 30 min – 3.6 KW

19 Heating system - analysis Minimum temperature variation Uniform heat absorption by charge 19

20 Cooling system Remove heat generated during curing reaction Depends on – Location of cooling lines – Size of cooling lines – Types of cooling lines – Length of cooling circuit – Flow rate of coolant Position of channels and time taken for cooling are analyzed in solidworks Best suitable mass flow rate of water selected for individual molds to have uniform decrease in temperature Uniform cooling Minimum warpage 20

21 Cooling system analysis Minimum temperature gradient b/w mold halves Min warpage 21 Ref : DSM design guide

22 Mold assembly 22

23 Process parameters Material - MS 4A Charge loading pattern – By trials during manufacturing Press capacity – 85 ton Press pressure – 2000 psi Process temperature – 150 deg C Mold pre heat time – 30 min Heater bore clearance – mm Cure time – 20 min Press parallelism – 0.001/ft (recommended values) Accurate control of the process High part repeatability 23

24 Future Scope Software simulation to predict – Fiber orientation – Charge pattern – Warpage – Closing speed – Material flow Software – Moldex 3d – Cadpress – Express – Autodesk moldflow beta Process simulation Animation reference : Moldex 3d 24

25 Conclusion Process dependency parameters are identified and analyzed Process data sheet preparation Future work involves manufacture of the mold and part Design Analysis Engineering drawing Part Material study Material selection Material Mold design Engineering drawing Heating system analysis Cooling system analysis Process parameters Process 25

26 Thank You 26 Questions and discussion

27 Analysis conditions PropertiesUnitsAl 6061 T6Al alloy Carbon epoxy Densitylb / in Youngs modulusmsi Poisson ratio Parts Wheel hub, existing wheel center Wheel rim Proposed wheel center Static Structural analysis 27

28 Heating system Electric heaters – less expensive, easy installation – Temperature gradient 10 deg c – Types Cartridge heaters (commonly used) Strip heaters (suitable for surface heating) Coil heaters (custom made to suit application) Wattage required for heating the mold in 30 min – 3.6 KW (heat required without losses = 3.1 KW + heat required for the charge = KW+ heat losses = 0.41 KW) Uniform temperature distribution uniform cure Image ref : 28

29 Mold – Al 6061 Heaters – SS 304 Analysis conditions Transient Thermal analysis (mold preheat time 30 min) 29

30 Analysis conditions Heat transfer coefficient: 25 W/m 2 /K External fluid temperature: °C Fluid - Water Solid - Aluminum 6061 Time : 10 min Thermodynamic parameters Static Pressure: lbf/in 2 Temperature: °C Solid parameters Default material: Aluminum 6061 Initial solid temperature: °C Fluid flow simulation 30


Download ppt "DESIGN AND ANALYSIS OF A COMPRESSION MOLDED CARBON COMPOSITE WHEEL CENTER VINOTH KUMAR DHANANJAYAN Thesis Defense for MS Mechanical Engineering April 3,"

Similar presentations


Ads by Google