Alusil


Alusil as a hypereutectic aluminium-silicon alloy contains approximately 78% aluminium and 17% silicon. This alloy was theoretically conceived in 1927 by Schweizer & Fehrenbach, of the Badener Metall-waren-Fabrik, 2a Hermannstraße, Baden-Baden; but practically created only by Lancia in the same year, for its car engines. It was further developed by Kolbenschmidt.
The Alusil aluminium alloy is commonly used to make linerless aluminium alloy engine blocks. Alusil, when etched, will expose a very hard silicon precipitate. The silicon surface is non-porous enough to hold oil, and is an excellent bearing surface. BMW switched from Nikasil-coated cylinder walls to Alusil in 1996 to eliminate the corrosion problems caused through the use of petrol/gasoline containing sulfur.
Engines using Alusil include: