ISBE GmbH Hospitalstr Stuttgart Tel: +49 (0)711/ Web:

Transcription

1 ISBE GmbH Hospitalstr Stuttgart Tel: +49 (0)711/ Web:

2 CFK-Valley Stade Convention 2012 Potentials of Novel FE-Simulation Techniques for the Machining of CFRP and Composite Materials Dr.-Ing. Kay Marschalkowski ISBE GmbH Tool Engineering Center, Germany Troy Marusich, Shuji Usui Third Wave Systems, USA 2

3 Presentation Outline About ISBE GmbH Motivations for modeling drilling Modeling considerations & metal cutting model verification Preliminary work in modeling composites Composite model validation Summary 3

4 ISBE GmbH, Germany Engineering & Software Product Modeling & Grinding Software Product and Process Optimization 4

5 Virtual Tool Design VTD Tool Engineering Tool-Designer 3D Suface Models TD WinNut TD Contour TD Point Advantage FEM 3D Model Import and Cutting Simulation AdvantEdge FEM TD Surface TD Thread Efficient & Effective Optimization of Cutting Tools 5

6 Motivation for Physics-Based Modeling Drill Holes are Everywhere Many holes in airframes and jet engines Burrs are problems in airframes Tooling development is difficult because the tool is inside the hole Drill has complicated geometry Many workpiece material types: metals, composites, multi-layer stacks BMW Boeing tistory Lamborghini 6

7 Thrust Force (N) Building the Model What is Important, What is Not? We need to understand the mechanics of drilling How does AdvantEdge FEM compare with experiment? Constant improvements to prediction ability Experimental Validation Experimental Predicted Compare thrust force & torque predictions to measurements Implementation of underlying physics in the FE workpiece models 7

8 Experimental Setup Mori Seiki NH axis machining center, 8,000 RPM spindle Kistler 9255B plate dynamometer (Fx, Fy, Fz Thrust Forces) Kistler 9125A rotary dynamometer (Mz, Fz Torque) Optiflex digital microscope, 220X optical zoom (Chips, Tool Wear) 8

9 Prediction (N) Drilling Model Validation Thrust force trends are improved Changed friction algorithm: Vrt models side flow at chisel edge better No effect for turning or milling View of workpiece with invisible drill Thrust Force Vrt Algorithm Validation Blank PilotHole Experiment (N) 9

10 AdvantEdge FEM Drilling Simulation 10

11 TWS Drilling Test & Prediction Comparisons Material: Al7050 Compare thrust forces and torques Two speeds (S1 low, S2 high), four feeds (F1 low, F4 high), two diameters (D mm, D mm) 11

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16 Composite Punch Shear Test Delamination 16

17 Composite Model Verification Setup for Orthogonal Cutting Simulation Tool 17

18 Oblique Cutting Simulation 0 Fiber Direction Pic.: Calzada, Illinois,

19 Oblique Cutting Simulation -45 Fiber Direction Pic.: Calzada, Illinois,

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23 Summary Prediction of drilling provides good results regarding trends for thrust force and torque Models recognize thermal, mechanical and geometric effects New modeling framework for composite drilling was developed The model represents the fiber orientation and strength in an orthotropic representation for each layer Fracture toughness models are used for delamination as well as fiber and matrix fracture 23

24 ISBE - Tool Engineering Center ISBE GmbH tterheim oftwaretechnik eratung und ntwicklung D Stuttgart ISBE TEC D Unna Germany