1. DEFORM Simulation Results 2D Hot Forging and Air Cool of Gear Tooth Geometry Holly Quinn 12/04/2010

2. DEFORM Model 2D Axisymmetric Model Workpiece (Yellow) is Plastic and 2200°F Top and Bottom Dies are Rigid. All pieces are 300°F. Workpiece will be re- meshed when interference exceeds 0.00099. Initial Contact Pairs: 1. WP to Bottom Die 2.WP to Top Die Top Die Bottom Die Workpiece

3. Forging Simulation Setup and Results

4. Forging Simulation Settings Main –Axisymmetric Geometry –Modes Deformation Heat Transfer Step Settings –Starting Step = -1 –Number of Steps = 100 –1 Step = 0.01” Die Displacement –Max Strain in WP/step = 0.1 –Primary Die = Top Die Iteration Settings –Solver = Skyline –Iteration Method = Newton-Raphson –Convergence Errors 0.001 for Velocity 0.01 for Force Process Conditions –Heat Transfer Environment Temperature = 68F Convection Coefficient=5.787e-6 But/sec/in 2 F –Diffusion Environment Atom Content = 1.69% atm Reaction rate coefficient = 1e-5 in/sec Advanced –Contact Error Difference Tolerations = 0.0009

5. Materials Top Die Workpiece Bottom Die

6. Temperature, Final Time step

7. Displacement Flash

8. Effective Stress

9. Effective Strain

10. Effective Strain Rate

11. FlowNet Tracking of Material Flow

12. Microstructure Post Processing of Forging Two Areas examined: –Points within gear “core” Points 6, 18, 21 –Points near exterior of gear tooth Points 14, 15, 16 Grain Orientation Plot Average Grain Size from beginning to end of forging (Step 1 – 43)

13. Microstructure Post Processing Settings Discrete Lattice: Cellular Automata, (50x50) Square Horizontal and Vertical BCs: Periodic, Wrap Around Grain boundary and Neighborhood: –Grain Boundaries coupled to material flow: No –Neighbor Hood: Moore’s Neighborhood, R=1 Dislocation Density Calculation Constants –ε 0 =1Q=416,780h 0 =0.00075 –r 0 =2000K=6000m=0.0055 Recrystallization Phenomena: DRX Nucleation Conditions for new grains: Function of a threshold dislocation density Nucleation Conditions for new grains: n/a Grain growth phenomena selection and material constants: –Grain Growth: Function of GB migration velocity, constant=1 Flow Stress phenomena selection and material constants: –n/a –ρ i = 1 –D=0.1 –δ=0.1 Initial MS Input: –Generate GB and orientations separately: System generate, average GS = 0 –Generate GB Orientations: System generate, random –Initial dislocation density ρ i =0.01

14. Microstructure – Core Locations Grain Orientation, Step 1 P6 P18 P21

15. Microstructure – Core Locations Grain Orientation, Step 43 P6 P18 P21

16. Microstructure – Core Locations Grain Size Histogram, Step 1 P18 P21 P6 Point 6: Average GS=9.70 Point 18: Average GS=9.50 Point 21: Average GS=9.76

17. Microstructure – Core Locations Grain Size Histogram, Step 43 Point 6: Average GS=2.05 Point 18: Average GS=1.89 Point 21: Average GS=2.02 P6 P18 P21

18. Microstructure – Core Locations Grain Boundary Misorientation, Step 1 P18 P21 P6

19. Microstructure – Core Locations Grain Boundary Misorientation, Step 43 P6 P18 P21

20. Microstructure – Tooth Locations Grain Orientation, Step 1 P16 P15 P14

21. Microstructure – Tooth Locations Grain Orientation, Step 43 P16 P14 P15

22. Microstructure – Tooth Locations Grain Size Histogram, Step 1 Point 14: Average GS=9.80 Point 15: Average GS=9.59 Point 16: Average GS=9.81 P16 P15 P14

23. Microstructure – Tooth Locations Grain Size Histogram, Step 43 Point 14: Average GS=1.97 Point 15: Average GS=2.07 Point 16: Average GS=1.91 P16 P15 P14

24. Decreased Grain Size in Core and Tooth Areas (from Step 1 to 43) Gear Core Grain Size Changes –Point 6: 9.70  2.05 –Point 18: 9.50  1.89 –Point 21: 9.76  2.02 Gear Tooth Grain Size Changes –Point 14: 9.80  1.97 –Point 15: 9.59  2.07 –Point 16: 9.81  1.91

25. Cooling Simulation Setup and Results

26. Air Cool Simulation Settings Pyrowear 53 Main –Axisymmetric Geometry –Modes Deformation Phase Transformation Mesh –#Structured Surface Mesh Layers=2 –Layer Thicknesses: 1=.005, 2=.01 Workpiece Initialization –Don’t Initialize Temperature –Phase Volume Fraction (Austenite)=1 –Temperature = 2200°F Step Settings –Starting Step = -44 (last step of forging) –(Max) Number of Steps = 1000 –1 Step = 5°F –Min Temp Time Step = 5 sec –Max Temp Time Step = 30 sec –Duration = 5400 sec Process Conditions –Heat Transfer Environment Temperature = 68F Coefficient= 5.787e-06 But/sec/in 2 F Boundary Conditions –Outside of Gear, all surfaces –Media Type = Air –Environment Temperature = 68°F –Convection Coefficient = 5.787e-06 But/sec/in 2 F –Symmetrical planes in vertical and horizontal directions Material –Pyrowear, Heat Treat *Heat Treat Wizard used for Model Setup

27. Pyrowear 53 Temperature (°F) Time Step #5 Time = 25 seconds Step #250 Time = ½ hour Step #425 Time = 1 ½ hrs

28. Pyrowear 53 Temperature (°F) Step #155 Time = 13 minutes ~1260°F

29. Pyrowear 53 Phase Transformation, Time=0

30. Pyrowear 53 Phase Transformation Time=1000 seconds Austenite Martensite Tempered Ferrite + Cementite Temperature

31. Pyrowear 53 Phase Transformation Time=1800 seconds Austenite Martensite Tempered Ferrite + Cementite Temperature

32. Pyrowear 53 Phase Transformation Time=5400 seconds Ferrite Martensite Tempered Ferrite + Cementite Tempered Martensite Temperature

33. Pyrowear Hardness Step 425, Time = 5400 seconds

34. Pyrowear 53 TTT Diagram

35. Pyrowear 53 Air Cool: Time Vs Temperature