| 摘要 |
<p>A recessed crown piston (10) of aluminium or aluminium alloy is manufactured by, either before or after machining a piston feature, treating the feature or the part of the piston which is to form the feature. The treatment is by the use of a laser beam, for example, and improves the mechanical properties of the feature or region to make it more resistant to damage. Similar techniques are applied to other piston parts.</p> |
