Core Viability Simulation for Salt Core Technology in High-Pressure Die Casting

  1. University of Erlangen-Nuremberg, Erlangen, GermanyB. Fuchs & C. Körner
  2. Casting Technology Development, AUDI AG, Ingolstadt, GermanyB. Fuchs & H. Eibisch

Corresponding author

Correspondence to B. Fuchs.

Abstract

In high-pressure die casting (HPDC) undercuts can only be fabricated by using complex high-maintenance sliders. Until now, this technology has not been used for large-scale and cost-sensitive serial applications. Sand cores from sand-and low-pressure die casting with organic and inorganic binder systems are not suitable for application in HPDC. Using lost cores made from sodium chloride may be a solution for HPDC. Due to the high dynamic forces during the casting process, core failure is still a problem, especially with high ingate velocities.

In this work, the use of numerical simulation is investigated to predict core failure during the casting process. The numerical results are compared with corresponding experiments to evaluate the simulation results with mechanical characterization. This way, an objective, data-based approach to find process parameters for the successful use of lost salt cores in HPDC without costly, time consuming trial-and-error-testing was established.

Keywords

  • High-pressure die casting (HPDC)
  • lost core
  • salt core
  • undercuts in HPDC
  • hollow parts in HPDC
  • casting simulation
  • fluid-structure-interaction
Figure 3. The specimen geometry with ingate and RYHUÀRZ DVPRGHOHGLQ WKH )'0PHVK LQ )ORZ' 7KH valve is used to simulate the vacuum-system used in the casting experiments
Figure 3. The specimen geometry with ingate and RYHUÀRZ DVPRGHOHGLQ WKH )'0PHVK LQ )ORZ' 7KH valve is used to simulate the vacuum-system used in the casting experiments
Figure 5. An HPDC part with the salt core still in place showing a typical core failure when the ingate velocity exceeds the critical limit of the core viability domain. This part was cast with an ingate velocity of 35m/s and a measured dwell pressure of 820bar with a preheattemperature of 175 C (347 F) for the salt core.
Figure 5. An HPDC part with the salt core still in place showing a typical core failure when the ingate velocity exceeds the critical limit of the core viability domain. This part was cast with an ingate velocity of 35m/s and a measured dwell pressure of 820bar with a preheattemperature of 175 C (347 F) for the salt core.

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