Thermal fatigue failure of brass die-casting dies

This research has been conducted to elucidate the mechanisms of brass die casting failure. A die was examined and we have evaluated the causes of crack failure mechanisms after use in brass die casting. The dominating failure mechanism in the investigated die was thermal fatigue cracking. Crack initiation is associated to accumulation of the local plastic strain that occurs during each casting cycle. The crack growth is facilitated by a number of elements: oxidation of the cracks’ surfaces, filling of brass and softening of the die material.

► Thermal fatigue is the first damage mechanism in the die-casting die. ► The crack initiation is due to an accumulation of the local plastic strain. ► Crack growth is facilitated by filling of cracks with brass and oxidation. ► The singularity plays an important role on the stress concentration.