ALUMINIUM-SILICON ALLOY ARTICLE AND METHOD FOR ITS PRODUCTION

摘要

A squeeze formed aluminium-silicon cylinder liner for an internal combustion engine is produced from a melt consisting essentially of the following composition by weight:- Silicon 14% to 16% Copper 1.9% to 2.2% Nickel 1.0% to 1.4% Magnesium 0.4% to 0.55% Iron 0.6% to 1.0% Manganese 0.3% to 0.6% Silicon Modifier 0.02% to 0.1% with the balance being aluminium and any unavoidable impurities, the as-formed article having an essentially eutectic microstructure containing not more than 10% of primary alpha-aluminium dendrites and being substantially free from intermetallic particles exceeding 10.mu. in diameter. The growth rate R of the solid phase during solidification is from 1,000 to 2,500 .mu./s and the temperature gradient G at the solid/liquid interface, expressed in .degree.C/cm is such that the ratio G/R is from 100 to 1,000 .degree.Cs/cm2.