Effect of minor Cu addition on the precipitation sequence of an as-cast Al-Mg-Si 6005 alloy

• Autorzy: Li K. , Song M. , Du Y. , Fang X.

Warianty tytułu

PL

Wpływ niewielkiej zawartości miedzi na sekwencje wydzieleń w odlewanych stopach Al-Mg-Si 6005

• Języki publikacji: EN

Abstrakty

EN

The whole precipitation sequences of two as-cast Al-Mg-Si 6005 alloys (containing no Cu or 0.1 wt.% Cu) at 150 degree Celsjus were investigated using X-ray diffraction, transmission electron microscopy and hardness examinations. The precipitation sequence of the Cu-free alloy can be expressed as: super-saturated solid solution (SSSS) → spherical G.P. zones → pre - β'' → β'' → U2 +Si + β _x → Si + β β _xwhile that of the Cu-containing alloy can be expressed as: SSSS → spherical G.P. zones + platelet-like G.P. zones → pre - β → β'' → Q' + β + Si → Q + β + Si. A new type of βprecipitate, namely β _x here, has been discovered in the Cu-free alloy. The addition of minor Cu is found to accelerate the microstructural evolution by inducing the formation of a new type of platelet-like G.P. zone along {111} _Al planes, and improve the hardening response at the over-aged stage by forming Q' and Q precipitates.

PL

Kompletna sekwencja wydzieleń dwóch odlanych stopów Al-Mg-Si 6005 (zawierąjacych 0 i 0.1%.wag Cu), w temperaturze 150 stopni Celsjusza, została zbadana przy użyciu dyfrakcji rentgenowskiej, transmisyjnej mikroskopii elektronowej i badań twardości. Sekwencja wydzieleń w stopie nie zawierającym Cu może być przedstawiona następująco: przesycony roztwór stały → sferyczne strefy Guiniera-Prestona → pre - β'' → β'' → U2 +Si + β _x → Si + β β _x natomiast dla stopu zawierającego Cu następująco: przesycony roztwór stały → sferyczne i płytkowe strefy Guiniera-Prestona → pre - β → β'' → Q' + β + Si → Q + β + Si. Nowy rodzaj wydzieleń β, tj. β x , został odkryty w stopie niezawierajacym Cu. Stwierdzono, że dodatek niewielkiej ilości Cu przyspiesza zmiany mikrostruktury poprzez indukowanie tworzenia nowego typu płytkowych stref Guiniera-Prestona wzdłuż płaszczyzny {111}_Al. i poprawia utwardzenie poprzez tworzenie wydzieleń Q' i Q.

Słowa kluczowe

EN

aluminum alloys; precipitation; ageing; phase transformation

PL

stopy aluminium; dyfrakcja rentgenowska; transmisyjna mikroskopia elektronowa; badania twardości

• Wydawca: Institute of Metallurgy and Materials Science of Polish Academy of Sciences ; Committee of Materials Engineering and Metallurgy of Polish Academy of Sciences
• Czasopismo: Archives of Metallurgy and Materials
• Rocznik: 2012
• Tom: Vol. 57, iss. 2
• Strony: 458--466
• Opis fizyczny: Bibliogr. 34 poz., rys., tab., wykr.

Twórcy

autor

Li K.

autor

Song M.

autor

Du Y.

autor

Fang X.

• State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China

Bibliografia

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