Die erosion and its effect on soldering formation in high pressure die casting of aluminium alloys

Erosion of the die material during die filling has long been regarded as a possible damage mechanism of dies in high pressure die casting (HPDC) of aluminium alloys. Melt impingement and erosion have also been proposed to be an important step leading to die soldering. However, there is little information in the literature on the direct measurement of any kind of die erosion in HPDC. The present analysis, based on existing erosion theories, has shown that liquid impingement and solid particle erosion is not likely to occur in HPDC in the short-term while soldering does. There is a paucity of data indicating how cavitation erosion may occur in HPDC in the short-term. Pins were examined that were used as soldering targets in specially designed dies during soldering trails using a semi-industrial HPDC machine. Although these pins were subjected to severe melt impingement during the trails, very little erosion occurred before the formation of soldered layers. (C) 1999 Elsevier Science Ltd. All rights reserved.