Abstract
Soldering reactions are commonly observed during high pressure die casting of aluminum alloys, and involve the formation of interfacial compound between the die and cast alloy. However, discussions on the effects of composition of die steel on interfacial reaction have not been reported. In this report, reaction couples were formed between various alloy steel (SK5, SKD61, SKD11) and molten AD12. The following results were obtained,
SKD11 containing lower silicon content than that of SKD61 reduced the soldering reaction. The mass loss of SKD11 reduced than that of SKD61 in molten AD12. In molten AD12, intermetallic layer composed of Al, Fe and Si was formed in every steel. The intermetallic layer was composed of two layers; the inner layer had a lower silicon content and the outer layer a higher content.
In molten AD12, the intermetallic layer SKD61 was formed of compact and broken layers. On the other hand, SKD11 showed a compact layer and a slight broken layer, while SK5 showed a compact layer but no broken layer.
