Method for manufacturing cylinder heads for combustion engines

The method comprises subjecting a thermal and/or mechanical material zone (10) of a cast part (1) to a post-treatment influencing a microstructure, and treating the material zone by a frictional agitation using a rotary pin (16), which is moved transverse to its rotational axis through the material zone. The movement step is carried out around a first opening formed in the cast part along an open or closed loop (S). A wall (21) of the first opening is supported from the interior by a mechanical thrust bearing (20) during post-treatment. The first opening is a valve opening of a cylinder head. The method comprises subjecting a thermal and/or mechanical material zone (10) of a cast part (1) to a post-treatment influencing a microstructure, and treating the material zone by a frictional agitation using a rotary pin (16), which is moved transverse to its rotational axis through the material zone. The movement step is carried out around a first opening formed in the cast part along an open or closed loop (S). A wall (21) of the first opening is supported from the interior by a mechanical thrust bearing (20) during the post-treatment. The first opening is a valve opening of a cylinder head. The thrust bearing is supported even over a further connection rigidly against the cast part except over the first opening. The end point (A2) and the starting point (A1) of the transverse movement of the rotary pin lie in a further opening, which is adjacently arranged to the first opening. The further opening is machined in a subsequent manufacturing step, and is an assembly opening for a diesel injection nozzle. Vorgeschlagen wird ein Verfahren zur Herstellung von Zylinderköpfen (1) für Verbrennungsmotoren aus im Kokillenguss geformten Al-Si-Legierungen. Mindestens eine thermisch und/oder mechanisch besonders beanspruchte Materialzone (10) des Gussteils wird einer die Gefügestruktur beeinflussenden Nachbehandlung unterzogen. Zur Steigerung der Gefügefeinheit in der Materialzone (10) wird diese durch Reibrühren mittels eines rotierenden Stiftes (16) behandelt, der quer zu seiner Rotationsachse durch die Materialzone (10) hindurch bewegt wird.