Advanced addition practices with AlSr rod for accurate and cost effective modification in the Casthouse and Aluminium Foundry

摘要

For optimum mechanical properties, AlSi casting alloys require microstructural modification by AlSr master alloys. These additions are usually carried out in the transport ladle or in the furnace long before casting. Consequently, such a procedure is relatively expensive due to the high strontium losses which occur throughout the process. Moreover, the consistency in the recovery of the Sr level in the as-cast products is limited. In this respect, the use of the fast dissolving AlSr rod in combination with the in-line and last-minute addition concepts, offers both an economically and technically perfect solution. The paper will describe casting tests which are illustrative of the fast dissolution and quick modification performance of the AlSr rod product. A number of addition methods will be outlined to explain how both concepts are nowadays applied practically in the casthouse and aluminium foundry.