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The long-term objective of this work is to develop design and modeling tools that allow the structural behavior of thin-walled cast components to be predicted when subjected to static and dynamic loads such as in crash situations. Here, the energy absorption potential of High Pressure Die Cast components made of magnesium alloys AM20, AM50, AM60, AZ91 and the aluminum alloy AlSi7Mg is investigated using a shear-bolt principle. For the AM60 alloy, single plates cast with different thickness have been tested in order to investigate the effect of plate thickness on the shear-bolt mechanism. It is found that this deformation principle gives an approximately constant mean force during the deformation process. The behavior seems to be very robust, especially for the magnesium alloys. A simple empirical model for prediction of the mean shearing force as a function of plate thickness and bolt diameter is proposed.

The effect of strain rate on tensile properties of cold chamber die cast AZ91D, AM60B and AM50A test bars is reported. The strain rate was varied from 15 s1- to 130 s-1, a range typical of deformation and crash. All tests were done at room temperature. The properties measured include fracture elongation and ultimate tensile strength values. The results are discussed in terms of the work hardening characteristics and strain rate sensitivities of the materials, and parameters in a material model suggested by Johnson-Cook have been determined. It has been found that flowstress increases and that elongation is not affected by strain rates from 15 s-1 to 130 s-1. The energy absorption during deformation increases therefore with the speed of deformation, emphasizing the positive properties of magnesium die cast alloys for safety related applications.

Permanent mould cast medallions and 3mm die cast test plates of 47 different AZ91 based alloys covering 3-129 ppm Ni, 7-2850 ppm Cu, 87-1740 ppm Si and 0-100 ppm Co were produced. Medallions and plates were subjected to 72 hours immersion in 5% NaCl solution at 25C and to the 10 day ASTM-B117 salt spray test. The results include: a) for AZ91, the corrosion rate values anticipated from salt spray testing of die cast test plates can be calculated from the results of immersion tests on permanent mould cast medallions; b) the effect of Co on corrosion of AZ91 is 35-75 times more detrimental than Cu and thus similar to that of Ni; and c) Si showed almost no effect on the corrosion rates in the alloys examined.