Naslov
Influence of heat treatment on AlSi7Mg(Cu) alloy properties development

Autori
Zovko Brodarac, Zdenka ; Stanić, Davor

Vrsta, podvrsta i kategorija rada
Radovi u zbornicima skupova, cjeloviti rad (in extenso), znanstveni

Izvornik
Conference Proceedings 57th International Foundry Conference, Portorož 2017 / Križman, Alojz ; Mrvar, Primož ; Medved, Jožef ; Schumacher, Peter ; Deike, Rudiger ; Jan-Blažić, Mirjam ; Petrič, Mitja - Ljubljana : Društvo livarjev Slovenije, 2017

ISBN
978-961-93723-6-4

Skup
57th International Foundry Conference, Creativity and Flexibility

Mjesto i datum
Portorož, Slovenija, 13.09.2017. - 15.09.2017

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
AlSi7Mg(Cu) alloy, copper, microstructure, heat treatment, mechanical properties

Sažetak
The design of materials through the selection of the chemical composition, thermodynamic modelling, melt treatment by inoculation and modification, correctly developed casting technology followed by adequate heat treatment could improve casting properties. Due to castings complex geometry and customer properties, casting manufacturers are forced to adopt production process with additional steps such as heat treatment. Rigorous regime with relatively high temperature and long holding time indicates the microstructural changes in the material, thus indirectly affects the mechanical properties of the material. An important aspect for further improvement and application is to develop a better understanding of the microstructural constituent changes due to performed heat treatment and consequently improved mechanical properties. Heat treatment is accompanied with increased costs and longer time for total production which cause lower competitiveness of casting producer per produced casting. Comparison of obtained properties in as-cast and heat-treated state reveals an evaluation of applied production procedures closely connected with investments in money and time vs. obtained properties improvement. Conventional AlSi7Mg alloy represent a frequent selection for complex geometry castings production. Designing of new chemical composition of AlSi7Mg(Cu) alloy with extra addition of Cu (up to 1.435 wt.%) represents a challenge in order to achieve advanced mechanical properties already in as-cast state. A wide range of complex reactions and intermetallic phases occurs due to numerous alloying (Si, Mg, Cu) and trace elements (Fe, Mn) interaction. Performed heat treatment influences on iron bearing phases’ morphology change, refining of microstructural constituents and enrichment of metal matrix on secondary alloying elements such as Cu and Mg. Exact determination of alloy behaviour was performed by modelling of equilibrium phase diagram, simultaneous thermal analysis and metallographic investigations in both states, as-cast and heat- treated, respectively. Heat-treated microstructure experiences the change like refining and uniform distribution of microconstituents, metal matrix enrichment on magnesium and copper, and therefore fragmentation of last solidifying phases’. Innovated chemical composition and determined solidification sequence of particular phases as well as theirs morphology and distribution comprehend to significant increase of tensile mechanical properties already in as-cast state. Heat treatment did not influenced on significant improve of mechanical properties.

Izvorni jezik
Engleski

Znanstvena područja
Metalurgija

POVEZANOST RADA