Effect of iron on the structure, hardening and physical properties of the alloys of the Al – Zn – Mg – Ca system

Recycling-Oriented Design of the Al-Zn-Mg-Ca Alloys

“…Unfortunately, the currently available CALPHAD databases do not count the existence of the Al10CaFe2 phase and the solubility of Zn in the (Al, Zn)4Ca phase. However, as our previous research on Al-Zn-Mg-Ca-Fe alloys [19] showed, the foregoing phases may appear as a result of non-equilibrium solidification induced by casting cooling rated, while slow-cooled samples included Al3Fe intermetallics. This case is quite similar to Al-Fe-Mg-Si alloys, which may exhibit Al8Fe2Si phase instead of Al5FeSi phase upon accelerated cooling rate [8].…”

“…Calcium seems to be far more preferential since it is the third most abundant metal in the earth's crust Recently, several works on Al-Ca-Fe-Si alloys showed that calcium may bind the impurities into finely shaped ternary phases Al10CaFe2 and Al2CaSi2 [17,18]. In our recent research on Al-Zn-Mg-Ca-Fe [19] and Al-Zn-Mg-Ca-Si [20] alloys we showed that the foregoing phases may appear as a very fine constituent. However, joint Ca, Fe and Si alloying has not been considered yet.…”

“…Heat treatment of the samples included two-step annealing 450 o C, 3h + 520 o C, 3h and quenching in water (hereinafter referred to as T4) that will be approved in the Results section. Ageing was performed as isochronal low-temperature exposure at 175 for 3 h that is corresponded to T6 condition [19,20]. The microstructure was examined in as-cast and T4 conditions by scanning electron microscopy (SEM, TESCAN VEGA3) with an electron microprobe analysis system (EMPA, Oxford Instruments) and Aztec software.…”

“…Calcium, abundant in the earth crust, also very versatile in aluminides formation, specifically Al10CaFe2 and Al2CaSi2, favouring flexibility in recycling-tolerant Al-Zn-Mg-Ca alloy design. Based on the available information [17][18][19][20], seven phases containing Ca, Fe and Si ((Al,Zn)4Ca, Al10CaFe2, Al2CaSi2, Al3Fe, Al8Fe2Si, Al5FeSi and Mg2Si) may be in equilibrium with (Al) in the alloys of the considered system. The most probable distribution of the elements among these phases is given in Table 2.…”

Al-Ca-M-La-Fe in-situ aluminum-matrix eutectic composites

“…Как известно, оно способно образовывать хрупкие интерметаллические включения и трещины за счет формирования напряженно-деформированного состояния в эвтектической области, что активно изучается путем микроструктурного, фрактографического, томографического и прочностных методов анализа на классических силуминах [17][18][19]. В то же время изучение легирующих систем Al-Zn-Mg-Ni-Fe и Al-Zn-Mg-Ca-Fe показало, что железо входит в состав интерметаллидных фаз эвтектического происхождения (например Al 9 FeNi и Al 10 СaFe 2 ) с благоприятной морфологией, обеспечивая сочетание высоких механических и технологических свойств сплава [20][21][22][23]. Выявление влияния железа на структуру и фазовый состав также является актуальной задачей в случае изучения естественных алюмоматричных композиционных материалов.…”