1. Redesign of Die Internal Structure Dr. Henry Tan School of Mechanical, Aerospace and Civil Engineering The University of Manchester

2. Finite Element Modeling Commercial software: ANSYS ABAQUS Thermal, structural analysis Mathematical details skipped

3. Model Cooling Process Sequentially coupled thermal/structural analysis: Input of structural analysis depends on the results from thermal analysis.

4. 1 st step: Geometry/Mesh Generation

5. 3D Mesh Generation Previous experience: 2D 3D Geometry description 3D mesh generation

6. Same Mesh for Thermal/Structural Analysis Same mesh Different thermal/structural element In sequentially coupled thermal/structural analysis: Geometry description

7. 2 nd step: Coupled Fields Analysis

8. Basics for Thermal Analysis Solve the heat balance equation Finite element solution gives: Nodal temperature

9. Transient Thermal Analysis Time dependent cooling load 50C/hour, to 500C Initial temperature distribution (at all nodes) 900C Need to define: Boundary condition Initial condition

10. Thermal Stress Analysis Input: nodal temperatures that a transient thermal analysis calculates Output: thermal stresses Solve the force balance equation

11. Thermal Material Properties Temperature dependence -> Nonlinear thermal analysis Thermal conductivity, 10.5 W/Km @ 20 C 30 W/Km @ 1000 C

12. Structural Material Properties Plasticity -> Nonlinear structural analysis 0.2% proof stress (as cast): 280 N/mm 2 @20 C, 195 N/mm 2 @870 C 110 N/mm 2 @900 C 80 N/mm 2 @1000 C, 45 N/mm 2 @1100 C Ultimate Tensile Strength: 470 N/mm 2 @20 C, 250 N/mm 2 @870 C, 145 N/mm 2 @900 C, 92 N/mm 2 @1000 C, 53 N/mm 2 @1100 C Thermal expansion coefficient:20-600C 17.8 x 10 -6 20-800C 18.2 x 10 -6 20-1000C 18.9 x 10 -6

13. Results from Finite Element Modeling Temperature-time curves for selected locations (corners) Stress-time curves for selected locations (corners) distortion-time curves for selected locations (corners) Temperature field (picture) at selected cooling time Stress field at selected cooling time Deformation field at selected cooling time Animation for temperature evolution on the die surface Animation for stress evolution on the die surface Animation for deformation evolution on the die surface