Cast light metal internal combustion engine crankcase production comprises exposing hard particles in hyper-eutectic aluminum-silicon alloy cylinder liners by fluid jet grit blasting with grit collection for recycling

摘要

Cast light metal crankcase production involves exposing hard particles in hyper-eutectic aluminum-silicon alloy cylinder liners (3) by fluid jet grit blasting with grit collection for recycling. A process for producing a cast light metal crankcase, incorporating cylinder liners of a hyper-eutectic aluminum-silicon alloy, comprises casting of the crankcase about cylinder liner blanks, coarse machining and fine drilling or turning of the running faces (8) of the liners (3) and then partial mechanical exposure of hard particles in the liner alloy structure so that plateau surfaces of the embedded particles stand proud. The partial exposure of the particles is effected by high energy blasting with a fluid jet (41) of fine abrasive fluid jet grit, collection and return channels (43, 46) for the fluid jet medium being located close to the two open ends of the liners (3) to prevent uncontrolled exit of the medium and/or grit into the environment.