A New Aluminum-9 Silicon Alloy with Low Iron, High Die Soldering Resistance, High Fluid Life for Permanent Mold Casting

摘要

There are several theories in the literature, not all consistent, that can be stated about the well known strontium additions to aluminum up to 0.02% for the purpose of modifying the eutectic silicon. Higher levels of strontium in the range 500 to 700 ppm and the benefits of such strontium additions to an Al-9% silicon alloy are less known and are the subjects of this paper. The alloy used in this study has a nominal silicon content of 9% and a magnesium range of 0.30-0.50% and has recently received the Aluminum Association designations of 367. The outboard swivel bracket is a very critical safety related part. All swivel brackets at Mercury Marine were converted from A356-T6 to 367-T6 three years ago because 367-T6 out performed A356-T6 in both static and impact tests at 40 miles per hour, and offered other process advantages.