Naslov
Effect of cooling rate on characteristic temperatures and microstructure development of AlSi9MgMn alloy

Autori
Zovko Brodarac, Zdenka ; Stanić, Davor

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of Abstracts of the 5th Central and Eastern Conference on Thermal Analysis and Calorimetry (CEEC-TAC5) and 14th Mediterranean Confrenece on Calorimetry and Thermal Analysis (Medicta2019) / Rotaru, Andrei ; Ciprioti, Stefano Vecchio - Rostock, 2019, 143-143

ISBN
978-3-940237-59-0

Skup
5th Central and Eastern European Conference on Thermal Analysis and Calorimetry (CEEC-TAC5) ; 14th Mediterranean Conference on Calorimetry and Thermal Analysis (Medicta2019)

Mjesto i datum
Rim, Italija, 27.08.2019. - 30.08.2019

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
AlSi9MgMn alloy, thermal analysis, cooling rate, characteristic temperature, microstructure

Sažetak
Aluminum alloys are widely applied in automotive, aircraft, food and building industries. Multicomponent AlSi9MgMn alloy intended for high pressure die casting (HPDC) has not been classified in international norm, neither EN nor AA, only briefly described in manufacturer norm [1]. Addition of particular alloying elements such as magnesium as well as manganese and iron can improve mechanical and technological properties of casting in dependence from solidification behaviour. Therefore, it is necessary to understand the influence of low cooling rates on characteristic transition and precipitation temperatures in relation to microstructure development. Thermodynamic calculation and thermal analyses revealed solidification sequence with corresponded temperatures in correlation to microstructure investigation as follows: development of primary dendrite network, precipitation of high temperature Al15(Mn, Fe)3Si2 phase, main eutectic reaction, intermetallic iron-magnesium phase precipitation Al8Mg3FeSi6 and secondary eutectic phase Al + Mg2Si as a final solidifying phase [2]. Solidification behaviour was investigated in situ through establishing the characteristic temperatures of phase transition and precipitation at low cooling rates started with the lowest 0, 17 K/s till highest 19, 49 K/s compared with those obtained by numerical simulation for HPDC at 63 K/s. Increase of cooling rate lower the characteristic temperatures and narrow the solidification interval of AlSi9MgMn alloy. It also changes the solidification manner and morphology of microconstituents. Higher cooling rate influences on refining of microconstituents in particularly primary dendrite network in particularly secondary dendrite arm spacing (SDAS). Correlation of microstructure features investigation and cooling rate reveals significant morphology change of intermetallic Al15(Mn, Fe)3Si2 phase from irregular coarse morphology at lowest cooling rate, Chinese script morphology at medium one and globular morphology at highest cooling rate [3]. Correlation of characteristic temperatures during solidification process and obtained microstructure of multicomponent AlSi9MgMn alloy in low cooling rate conditions comprehends to evaluation of applicability of this material for thick-walled safety critical parts and sets in automotive industry.

Izvorni jezik
Engleski

Znanstvena područja
Metalurgija

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