Application of aluminium hybrid composites in automotive industry

Abstract

Subject reviewStrict requirements that are put on mechanical constructions from the aspect of increase of exploitation periods and reduction of their weights, therefore of their prices as well, implicate developments and applications of new composite materials with matrices of lightweight metals. Composite materials with metal matrices are used for engine cylinders, pistons, disc and drum brakes, Cardan shafts and for other elements in automotive and aviation industry. The most important type of metallic materials is composite materials with matrices of aluminium alloys due to a set of their beneficial properties. Improvement of mechanical, especially tribological properties of hybrid composites were provided by the use of certain reinforce materials such as SiC, Al2O3 and graphite in defined weight or volumetric share. New developed hybrid composites with aluminium matrices have significantly higher resistance to wear, higher specific stiffness and higher resistance to fatigue. By the increase of quantities of produced elements made of hybrid composites, decrease of their prices is induced that even further enlarge their applications. The applications of aluminium hybrid composites are considered from the aspect and with the focus on automotive industry. Keywords: aluminium; application; automotive industry; composites; MMC Primjena aluminijskih hibridnih kompozita u automobilskoj industrijiPregledni članak Pooštravanje konstrukcijskih zahtjeva s aspekta povećanja radnog vijeka i smanjenja mase, a samim tim i cijene konstrukcije, iniciralo je razvoj i primjenu novih materijala s osnovom od lakih metala. Kompoziti s metalnom matricom nalaze sve veću primjenu pri izradi košuljica cilindara motora, klipova, kočionih diskova i doboša, kardanskih vratila kao i drugih dijelova u automobilskoj i avio industriji. Posebno mjesto, od svih metalnih materijala, zauzimaju kompoziti na osnovi legure aluminija zbog niza dobrih svojstava. Poboljšanje mehaničkih, a posebice triboloških karakteristika hibridnih kompozita moguće je uporabom određenih ojačivača, najčešće SiC, Al2O3 i grafita, u odgovarajućem masenom ili volumenskom udjelu. Novodobiveni hibridni kompoziti s aluminijskom osnovom imaju znatno povećanu otpornost na habanje, povećanu specifičnu krutost i povećanu otpornost na zamor. Povećanjem količine proizvedenih dijelova od aluminijskih kompozitnih materijala dolazi do smanjenja cijene ovih dijelova, što dodatno povećava područje njihove primjene. U radu su prikazani primjeri primjene aluminijskih hibridnih kompozita s osvrtom i težištem na automobilskoj industriji.

Application of Aluminum and Aluminum Alloys in Engineering

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“…3. Primary processes of production of aluminum alloys [3] The choice of treatment types of aluminum alloys depends on many factors that include the type and level of the reinforcement of the alloy and the desired degree of integration of the microstructure.…”

Machinability improvement of powder metallurgy steels

“…Tool life, tool wear, machinability and understanding chip formation mechanism have been highlighted in that article. These materials are really important and widely used nowadays in the automotive industry [13].…”

Mechanical, Microstructure and Wear Behaviour of LM25/SiC/Mica Metal Matrix Composite Fabricated by Squeeze Casting Technique

“…The heat treated LM25 alloy has fairly good machining properties, but tools need to be of high speed steel and must be kept sharp. A moderately high rate of tool wear can be expected during machining [8]. LM25 is highly resistant to corrosive attack by sea water and high marine atmospheres.…”