MECHANICAL STRENGTH AT THE INTERFACE OF A STEEL AXLE INSERTED IN AN ALUMINUM PERMANENT MOLD CASTING

摘要

An aluminium skate-board truck including two steel inserts was poured in a permanent mold and the metallurgical characteristics at the interface were investigated. No chemical interaction between the aluminium near-eutectic AlSi13 alloy and the steel rods was observed. The mechanical adherence at the aluminium-steel interface was measured for insert preheating temperatures of 150°C and 350°C. Preheating the insert to a higher temperature was found to enhance the adherence of the aluminium casting to the steel insert. By modeling filling and solidification, it was possible to determine the thermal conditions all along the interface. It was found that the adherence increased from 6 to 14 MPa when the local solidification time at the interface increased from 3 s to 15s.