Redesign of Die Internal Structure

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Redesign of Die Internal Structure
Dr. Henry Tan School of Mechanical, Aerospace and
Civil Engineering The University of Manchester
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Finite Element Modeling
ANSYS ABAQUS Thermal, structural analysis
Commercial software
Mathematical details skipped
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Model Cooling Process
Sequentially coupled thermal/structural
analysis Input of structural analysis depends
on the results from thermal analysis.
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1st stepGeometry/Mesh Generation
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3D Mesh Generation
Previous experience 2D
3D Geometry description 3D mesh generation
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Same Mesh for Thermal/Structural Analysis
Geometry description
In sequentially coupled thermal/structural
analysis
Same mesh Different thermal/structural element
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2nd stepCoupled Fields Analysis
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Basics for Thermal Analysis
Solve the heat balance equation
Finite element solution gives Nodal temperature
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Transient Thermal Analysis
Need to define
Boundary condition
Time dependent cooling load 50C/hour, to 500C
Initial temperature distribution (at all
nodes) 900C
Initial condition
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Thermal Stress Analysis
Solve the force balance equation
Input nodal temperatures that a transient
thermal analysis calculates Output thermal
stresses
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Thermal Material Properties
Thermal conductivity, 10.5 W/Km _at_ 20 ?C
30 W/Km _at_ 1000 ?C
Temperature dependence -gt Nonlinear thermal
analysis
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Structural Material Properties
Thermal expansion coefficient 20-600C 17.8 x
10-6 20-800C 18.2 x 10-6 20-1000C 18.9 x
10-6
0.2 proof stress (as cast) 280 N/mm2_at_20?C,
195 N/mm2_at_870?C 110 N/mm2_at_900 ?C
80 N/mm2_at_1000 ?C, 45 N/mm2_at_1100 ?C
Ultimate Tensile Strength 470 N/mm2_at_20?C,
250 N/mm2_at_870?C, 145 N/mm2_at_900?C,
92 N/mm2_at_1000?C, 53 N/mm2_at_1100?C
Plasticity -gt Nonlinear structural analysis
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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