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High Pressure Die Casting of Light Metals
Heat Transfer and Microstructure
Raimo Helenius
SUP 03.03.05
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Outline

• Different aspects of the project
• Heat transfer coefficient in the shot sleeve
• Heat transfer coefficient in the die
• Microstructure
• Shot sleeve filling and Simulation
• Modeling of the shot sleeve ? Geometry
• Simulation vs. experiments
• Mould
• The principal of casting trails in Porsgrunn
• Microstructure
• SDAS in a HPDC product
• SDAS vs. Cooling rate

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Different parts to be considered
Microstructure
Mould/Die
Shot sleeve
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Geometric description of the shot sleeve
Geometric description of the shot sleeve
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Model used in MagmaSoft

• Volumes needed for simulation
• Can model the geometry using AutoCad or
  MagmaSoft
• Fill ratio 47 (Based on a box shaped geometry)

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Location of thermocouples in model
Thermocouples
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Estimation of the HTC

• Assume a heat transfer coefficient
• Depends on metal temperature
• Compare with casting experiments

• Mesh dependent

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Simulation of shot sleeve filling
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Simulation vs. Experiments

• Metal temp 680ºC ( 700000)
• Fill time 3 sec.
• Polished surface

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Heat transfer coefficient in the die
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Microstructure in a HPDC casting
- AlSi11

• SDAS 4.3µm
• Cooling rate ?

- Work done by S. Ghetti
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Cooling rate vs. SDAS
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Cooling rate vs. SDAS