Influence of melt treatment by inoculation on microstructure and mechanical properties development of AlSi12 alloy

Zahvaljujući širokoj lepezi povoljnih svojstava, aluminijske legure pronalaze primjenu u svim industrijskim granama. Radi poboljšanja mehaničkih, fizikalnih i korozijskih svojstva aluminijskih legura osnovnom elementu dodaju se legirajući elementi poput silicija, bakra ili magnezija te elementi u tragovima poput željeza, mangana, titana, bora, stroncija ili natrija. Njihov primarni utjecaj, ali i međusobna interakcija doprinijet će ciljanom razvoju mikrostrukture koja će indirektno utjecati na poboljšanje zahtijevanih svojstava. Važnu ulogu pritom ima i odabir tehnologije koja će utjecati na brzine hlađenja i/ili skrućivanja te pritom sinergijski s dodanim elementima činiti osnovu razvoja mikrostrukture i konačnu upotrebnu vrijednost odljevaka. U ovome radu ispitana je EN AlSi12 (DIN 230) legura namijenjena visokotlačnom lijevanju. Proizvedena je i praćena kvaliteta AlSi12 legure s različitom obradom taline: AlSi12 s dodatkom modifikatora AlSr10 te AlSr12 s dodatkom modifikatora AlSr10 i cjepiva AlTi5B1. Hipoteza istraživanja bazira se na pretpostavci da se ciljanom obradom taline utječe na slijed skrućivanja, razvoj mikrostrukturnih značajki, a time i postignuta mehanička svojstva legure.Due to a wide array of favourable properties, aluminium alloys are used in all industrial branches. Elements like silicon, copper or magnesium, along with trace elements such as iron, manganese, titan, boron, strontium or sodium are added in order to improve mechanical, physical and corrosion properties of aluminium alloys. Their primary effect, as well as their interaction will lead to the development of microstructure, thus resulting in improvement of desired properties. The choice of technology which will impact the speed of cooling and/or solidification, along with making the base for the improvement of microstructure and final worth of the casts in synergy with added elements, is of great importance. This paper examines EN AlSi12 (DIN 230) alloy intended for high pressure casting. Produced alloy AlSi12 with different way of melt processing was monitored for quality. Different ways of melt processing were AlSi12 with addition of AlSr10, and AlSr12 with addition of AlSr10 and AlTi5B1 refiner. Hipothesis of the examination is based on the assumption that targeted processing of melts can influence the sequence of solidification, development of microstructural characteristics and finally the acquired mechanical properties of the alloy