Cylinder head and motor block castings

A method for manufacturing a cylinder head and motor block casting, including an aluminum alloy having Si 6.80-7.20, Fe 0.35-0.45, Cu 0.30-0.40, Mn 0.25-0.30, Mg 0.35-0.45, Ni 0.45-0.55, Zn 0.10-0.15, Ti 0.11-0.15, the remainder being aluminum and impurities of a maximum content of 0.05 each, but not more than a maximum of 0.15 impurities in all, and wherein at least 1 vol. % of the following phases of the aluminum-nickel type, aluminum-copper type, aluminum-manganese type, aluminum-iron type and mixed phases of the aforesaid types, comprising the step of

• a) filling an aluminum alloy into a casting mold at a temperature of 720° to 740° C.;
• b) cooling the aluminum alloy at a cooling rate of 0.1 to 10 K s−1;
• c) carrying out a thermal treatment after the cooling to room temperature is accomplished by
• providing a solution heat treatment at 530° C. for 5 hours;
• and
• chilling in water at 80° C. and artificial ageing at a temperature of 160 to 200° C. for 6 hours.