Aluminium matrix composites in modern automotive industry

Rad prikazuje svojstva, sastav i vrste aluminijskih kompozitnih materijala koji se koriste u suvremenoj automobilskoj industriji te njihove suvremene postupke dobivanja. Aluminijski kompozitni materijali imaju široku primjenu u suvremenim automobilskim industrijama. Njihove karakteristike su temeljene na upotrebi ojačala kako bi se poboljšala učinkovitost i svojstva matrice. Ojačala se najčešće pojavljuju u tri oblika - viskeri, vlakna i žice. Mehanička, fizikalna i tribološka svojstva ovih kompozita su naprednija nego kod uobičajenih materijala, a posebice se izdvaja mehanička čvrstoća, krutost, težina, otpornost na trošenje i koroziju. Zbog niske gustoće i malih masa pogodni su za izradu blokova motora, klipova, klipnjača i disk kočnica, a uvelike smanjuju i potrošnju goriva. Proizvode se postupkom lijevanja i miješanja, gdje se tekućem aluminiju dodaju čestice silicijeva (SiC) ili titanijeva (TiC) karbida u obliku vlakana. Relativno su skupi jer se najčešće kombiniraju sa silicijevim i titanijevim karbidima, koji im značajno povisuju tvrdoću, vlačnu čvrstoću i otpornost na trošenje i time produljuju vijek trajanja konstrukcijskih dijelova.The thesis presents the properties, composition and types of aluminium matrix composites used in modern automotive industry, and the respective advanced production technologies. Aluminium composite materials have a high application in modern automotive industry. Their characteristics are based on reinforcements which improves the matrix performances. Reinforcements can be shaped into three forms - whiskers, fibres and strings. Mechanical, physical and tribological properties of composites which include mechanical strength, stiffness, weight, corrosion and wear resistance are greatly improved when compared to standard materials. They are suitable for designing engine blocks, pistons, piston rods and disc brakes because of their low density and low mass, and they greatly reduce fuel consumption. They are produced with stir casting, where melted aluminium is being reinforced with silicon (SiC) and titanium (TiC) carbides.They are relatively expensive because of their combination with silicon and titanium carbides, which significantly increase hardness, tensile strength, wear resistance and lifetime of construction parts