Heat treatment procedure of aluminum-based alloy cylinder heads, and cylinder heads that have improved fatigue resistance properties

摘要

Heat treatment procedure of a cylinder head cast iron part made of aluminum, silicon and magnesium alloy, characterized in that it comprises the following steps: - placing the part in solution for a period of between three and ten hours, a a temperature between 490 ° C and 550 ° C; - quenching of the piece in the air or in a fluidized bed, at a cooling rate such that the temperature of a fire side of the piece goes from 495 ° C to 200 ° C in less than 7 min 30 s; - tempering of the piece at the resistance peak, or near the resistance peak, the tempering being performed according to a time adapted to reach a resistance level of the piece at least equal to 85% of the maximum resistance level, at tempering temperature considered.