On the working surface of a casting die cracks appeared after less than 1000 shots and caused imprints on AlSi9Cu3 alloy castings. The cracks on the surface are visible with magnifying glass observation. Material selection, die design and thermal stress fatigue due to the working conditions, as well as the inhomogeneous and low initial die temperature contribute to the crack formation. The intensity and homogeneity of the temperature field on the working surface of the fixed-die half during the preheating process were checked using thermographic analysis.
|