Cold Chamber Die Casting Cold Chamber Die Casting for Increased Quality and Reduced Costs
Cold-chamber die casting is the most popular process in the mass production of light metal castings. Magmasoft explains key factors for the realization of a cost-reduced lightweight design concept.
Currently, half of the world’s production is manufactured using this technology, while continuous improvements in quality are broadening its application for automotive components. A development project of the Italian studio DSM showed key factors for the realization of a cost-reduced lightweight construction concept with simultaneous process reliability for an aluminum die casting with high functional performance requirements in the automotive sector. Figure 1 of the picture gallery shows this.
Virtual Preliminary Study
The component is a cover that ensures maximum operational reliability in both structural strength and hydraulic seal to prevent oil leakage. Due to the high quality requirements, the Italian engineers carried out a virtual preliminary study on the performance of the tool in production in order to identify critical problems for the internal integrity of the component at an early stage (see Figure 2 of the picture gallery).
The virtual analysis of the initial configuration highlighted critical points: the solidification did not provide satisfactory results due to isolated shrinkage in areas of the component which must ensure a hydraulic seal. It was therefore decided to investigate alternatives for the gating system, especially focusing on the component’s heaviest section, with the objective to reduce the shrinkage porosity to a minimum while limiting entrapped air. As Figure 3 shows, the changeover to a four-cavity mould has reduced operating costs in production and kept maintenance costs for the tools to a minimum.
The new lay-out reduced the critical aspects for internal integrity in the heavy section. Once a satisfactory lay-out was identified, the design was completed by defining an appropriate thermal control system, (see Figure 4 of the image gallery).
Simulations for Verification
With the corresponding simulations, the dimensioning of the cooling lines and the corresponding process parameters were virtually checked. Figures 5 and 6 show that the expected improvements, which allow a direct transition from the design to the manufacturing phase, were confirmed by the results obtained.
The sampling phase of the new die was satisfactorily concluded using process parameters corresponding to those defined for the final simulation. The most interesting result was that the required quality could be obtained at a lower cost than the one foreseen - in a very limited development time. Stefano Chiarello, the Studio DSM designer who worked on the virtual analysis of the process, summed up his project experience: “I have realized the usefulness of the software for decision-making support, especially when experience was suggesting to me that the assumptions initially taken into account could be risky”.
This article was first published by MAGMASOFT.