| 摘要 |
<p>Aluminium-based article having a heat and corrosion protective coating, especially engine parts such as piston crown or cylinder head, and a method of preparing said article. The coating consists of an aluminium-based bonding layer, preferably having a thickness in the range 0.1-0.6 mm, and an outer top layer of stabilized or partially stabilized zirconium dioxide, preferably having a thickness in the range 0.5-2.5 mm, and optionally a cermet layer, comprising zirconium dioxide and an aluminium-based metal component, between the bonding layer and the outer zirconium dioxide top layer. The bonding layer is applied to the substrate by thermal spraying of a rapidly solidified powder, substantially consisting of 60-80% by weight of Al and 40-20% by weight of Si, the particles of the powder having a frozen unstable micro-structure. The cermet layer desirably is a layer consisting of zirconium dioxide and an aluminium-based alloy, the metal content of the cermet layer decreasing substantially uniformly in the direction towards the outer zirconium dioxide top layer. The cermet layer preferably has a thickness in the range 0.2-0.6 mm. Also the cermet and zirconium oxide layers are deposited by thermal spraying.</p> |
