Ci a ion: Šmalc, J.; Vonˇcina, M.;
M a , P.; Balaško, T.; K u iš, V.;
Pe iˇc, M. The In luence o Found y
Sc ap Re u ns on Chemical
Composi ion and Mic os uc u e
De elopmen o AlSi9Cu3 Alloy.
C ys als 2023,13, 757. h ps://
doi.o g/10.3390/c ys 13050757
Academic Edi o : Hongbin Bei
Recei ed: 12 Ap il 2023
Re ised: 28 Ap il 2023
Accep ed: 30 Ap il 2023
Published: 3 May 2023
Copy igh : © 2023 by he au ho s.
Licensee MDPI, Basel, Swi ze land.
This a icle is an open access a icle
dis ibu ed unde he e ms and
condi ions o he C ea i e Commons
A ibu ion (CC BY) license (h ps://
c ea i ecommons.o g/licenses/by/
4.0/).
c ys als
A icle
The In luence o Found y Sc ap Re u ns on Chemical
Composi ion and Mic os uc u e De elopmen o
AlSi9Cu3 Alloy
Jan Šmalc 1, Maja Vonˇcina 2, P imož M a 2, Tilen Balaško 2, Vladimí K u iš 3and Mi ja Pe iˇc 2,*
1Labo a o y o Hea T ea men and Ma e ials Tes ing, Facul y o Mechanical Enginee ing,
Uni e si y o Ljubljana, 1000 Ljubljana, Slo enia; [email p o ec ed]
2Depa men o Ma e ials and Me allu gy, Facul y o Na u al Sciences and Enginee ing, Uni e si y o
Ljubljana, 1000 Ljubljana, Slo enia; [email p o ec ed] (M.V.); [email p o ec ed] (P.M.);
[email p o ec ed] (T.B.)
3Ins i u e o Manu ac u ing Technology, Facul y o Mechanical Enginee ing, B no Uni e si y o Technology,
616 69 B no, Czech Republic; [email p o ec ed].cz
*Co espondence: [email p o ec ed]; Tel.: +386-31-317-155
Abs ac :
Recycling is now, mo e han e e , an impo an pa o any ound y p ocess due o he
high cos o ene gy. The basis o he wo k p esen ed he e is a s udy o he addi ion o ound y sc ap
e u ns o he mel in o de o educe ma e ial and ene gy cos s. The mos impo an issue in such a
p ocess is he quali y o bo h he p epa ed mel and inal p oduc . In his wo k, sc ap e u ns we e
added o he AlSi9Cu3 base alloy in di e en p opo ions. Chemical composi ion was moni o ed,
he solidi ica ion pa h was p edic ed by CALPHAD calcula ions and moni o ed by he mal analysis,
and he o med mic os uc u e was s udied. The mechanical p ope ies we e also de e mined. The
esul s showed ha as he amoun o sc ap e u ns inc eased, elemen s such as Fe, Ni, Pb, S , e c.
we e mo e buil up and elemen s such as Mg, Mn, C , e c. we e dec eased due o oxida ion. The
di e en chemical composi ion led o a educed Mn:Fe a io, esul ing in he o ma ion o needle-like
Fe- ich phases and a dec ease in mechanical p ope ies.
Keywo ds: cas ing; ound y sc ap e u n; ecycling; solidi ica ion; Al cas alloys
1. In oduc ion
In ound ies and wi hin he aluminium indus y, he demand o aluminium alloys
o he au omo i e indus y is cons an ly inc easing due o hei good speci ic s eng h and
co osion esis ance. Mos o he aluminium comes om p ima y p oduc ion, i.e., om
elec olysis. Howe e , he p oduc ion o seconda y aluminium is inc easing apidly [
1
,
2
].
Fi s ly, due o he high p ice o p ima y alloys, ound ies o en use ecycled ma e ials o
inc ease he e iciency and p oduc i i y o he p ocess. Secondly, he euse o ecycled and
sc ap pa s sa es up o 95% ene gy compa ed o he p oduc ion o p ima y aluminium,
esul ing in less g eenhouse gas emissions [3–5].
The solidi ica ion o heAlSi9Cu3(Fe) alloy has been s udied by a ious esea che s
[6–8]
.
Solidi ica ion depends on he chemical composi ion and cooling a e and s a s wi h he
nuclea ion o p ima y
αAl
dend i es a abou 610–570
◦
C. Soon a e , he o ma ion o i on-
ich phases such as
α
-Al
15
(Mn,Fe)
3
Si
2
and/o
β
-Al
5
FeSi occu s. Eu ec ic c ys allisa ion
o (
αAl
+
βSi
) begins a 566
◦
C, ollowed by he o ma ion o Mg
2
Si (i he c i e ia a e
me ). Subsequen ly, he o ma ion o he coppe - ich phase begins in he inal s age o
solidi ica ion, in which he i s o ma ion o he θ-Al2Cu phase akes place. Solidi ica ion
is comple ed wi h he complex eu ec ic Q-Al
5
Mg
8
Si
6
Cu
2
phase in he empe a u e ange o
~495–451 ◦C [9,10].
When using seconda y aluminium, he e iciency o he p ocess is lowe due o he
highe slag con en . Secondly, many impu i ies a e in oduced in o he mel wi h seconda y
C ys als 2023,13, 757. h ps://doi.o g/10.3390/c ys 13050757 h ps://www.mdpi.com/jou nal/c ys als
C ys als 2023,13, 757 2 o 13
aluminium. I on is one o he main elemen s ha o m i on- ich in e me allic phases,
including he less ha m ul
α
-Al
15
(Mn,Fe)
3
Si
2
phase wi h “Chinese sc ip ” mo phology and
ha m ul
β
-Al
5
FeSi needles [
11
]. To a oid he o ma ion o
β
-Al
5
FeSi, di e en me hods can
be used: mel supe hea ing, highe cooling a es, and chemical modi ica ion. In p ac ise,
he Mn:Fe a io = 0.5 is mos o en main ained [
12
]. Wi h he addi ion o ecycled and sc ap
pa s, he chemical composi ion changes and i is known ha he concen a ions o Mg and
Mn dec ease due o oxida ion. Bo h elemen s play an impo an ole, i s ly in he o ma ion
o
α
-Al
15
(Mn,Fe)
3
Si
2
, and secondly, he p esence o Cu and Mg allows addi ional ha dening
o he AlSi9Cu3(Fe) alloy by hea ea men o na u al ageing. Du ing ageing,
θ
-Al
2
Cu
and/o Mg
2
Si p ecipi a es a e o med, which lead o an inc ease in ensile s eng h (Rm)
and ha dness o he AlSi9Cu3(Fe) alloy [
13
]. Fu he mo e, g ain e inemen o p ima y
αAl
wi h Al-Ti-B mas e alloy is o en used o imp o e Rm and ha dness o aluminium
alloys [
14
,
15
]. Modi ica ion o eu ec ic
βSi
by he addi ion o S is also a well-known
p ac ise [
16
]. When S -modi ied sc ap is added o he mel , he chemical composi ion o
Ti, B, and S inc eases, and en ichmen o hese elemen s can lead o he o ma ion o new
S - ich in e me allic Al2S Si2[17,18].
The aim o he p esen s udy was o obse e he e ec s o di e en amoun s o sc ap
e u ns on he chemical composi ion o he cas ings. The main ocus o he s udy was on
he cooling cu es and changes in mechanical p ope ies, such as ensile s eng h, yield
s eng h, and ha dness, which change due o na u al ageing.
2. Ma e ials and Me hods
The wo k was based on he p oduc ion o specimens om a base alloy wi h di e en
amoun s o ound y sc ap e u ns. Found y sc ap e u ns in his con ex mean he ejec ed
cas ings om ga ing and eede sys ems ha a e ecycled du ing he p oduc ion o cas ings
a e e y ound y and a e a necessi y in cas ing p oduc ion. The amoun o cas ings ejec ed
om ga ing and eede sys ems du ing b u cas ing is usually om 30% o 50% o mo e,
which is why ound y sc ap e u ns a e an impo an pa o he cha ge ma e ial. Usually,
he ound y sc ap e u ns used in he p oduc ion o new cas ings a e om he same alloy
as he cas ings p oduced. The alloy used o he expe imen was a s anda d AlSi9Cu3
base alloy (chemical composi ion gi en in Table 1) o which sc ap e u ns desc ibed abo e
(chemical composi ion gi en in Table 2) we e added in quan i ies anging om 0% o
100%. Table 2shows he designa ions o he samples and he addi ions o e u n sc ap. The
samples o abou 2000 g we e mel ed in an induc ion u nace wi h a s eel c ucible. A e
mel ing, he empe a u e was aised o 700
◦
C, and g ain e ine s (0.02 w % Ti in he AlTi5B1
mas e alloy) and modi ie s (0.01 w % S in he AlS 10 mas e alloy) we e added. The mel
was degassed wi h a labo a o y impelle a 600 pm and an a gon gas low o 3 L/min
o 120 s. The mel s p epa ed in his way we e pou ed in o a C oning measu ing cell o
simple he mal analysis, whe e he empe a u e was eco ded o e ime. The emainde o
he mel was pou ed in o a squa e s eel mould ha was p ehea ed o 450
◦
C. The cas ings
om he C oning measu ing cell we e cu o chemical analysis, di e en ial scanning
calo ime y (DSC), and me allog aphic obse a ions. The cas ings om he s eel mould
we e used o p epa e ensile and ha dness es specimens. Figu e 1shows he mel ing
p ocedu e, he cas samples, and he sec ions o he abo e analyses. Chemical analysis
was ca ied ou by induc i ely coupled plasma–op ical emission spec ome y (ICP–OES)
using an Agilen 5800 VDV ins umen and me allog aphic obse a ions we e made by
op ical me allog aphy and scanning elec on mic oscopy (SEM) using an Olympus BX 61
mic oscope and Jeol JSM-6500F SEM wi h an EDS de ec o , espec i ely. Round ensile es
specimens (DIN 50125) we e es ed 35 days a e cas ing he samples, wi h ou eplica es
using he INSTRON 8802 machine acco ding o SIST EN ISO 6892-1 A224. B inell ha dness
(HBW 2.5/62.5) measu emen s we e aken o 35 days a e cas ing o ollow he na u al
ageing p ocess, wi h wo epe i ions o each sample using a NEXUS 7500 es e . Based on
he chemical composi ion, CALPHAD simula ions o he phase diag ams we e calcula ed
C ys als 2023,13, 757 3 o 13
o all alloys using The moCalc 2020a so wa e and he TCAL6 da abase. In addi ion, he
non-equilib ium solidi ica ion cou se o each alloy was p edic ed using he Scheil model.
Table 1. Chemical composi ion o AlSi9Cu3 base alloy and ound y sc ap e u ns in w %.
Elemen Si Fe Cu Mn Mg C Ni Zn
Base 7.51 0.5973 2.955 0.2738 0.3366 0.0407 0.0244 0.6846
Sc ap 7.504 0.6095 2.995 0.1838 0.2547 0.0305 0.0432 0.7343
Elemen Ti Ag B Be Bi Ca Cd Ce
Base 0.0951 <0.00001 0.0015 0.00001 0.002 0.0022 0.00019 <0.00010
Sc ap 0.108 <0.00001 0.0021 0.00001 0.0031 0.00083 0.00032 <0.00010
Elemen Co Ga Hg Li Na P Pb Sb
Base 0.0014 0.012 <0.0001 0.00003 <0.00002 0.0009 0.0367 0.0022
Sc ap 0.00083 0.0125 <0.0001 0.00003 <0.00006 0.00083 0.0582 0.0006
Table 2. Sample designa ions and addi ions o sc ap e u ns o he base alloy.
Sample
Designa ion
Base
Alloy/w % Base Alloy/g Sc ap
Re u n/w % Sc ap Re u n/g
226-100 100 2030.8 0 0
226-80 80 1607.0 20 414.5
226-60 60 1200.8 40 784.1
226-40 40 795.2 60 1204.7
226-20 20 395.1 80 1620.6
226-00 0 0 100 2030.7
Figu e 1.
(
a
) Mel ing in a s eel c ucible; (
b
) Cas ing om s eel mould o mechanical es ing; (
c
) Cas -
ing om C oning cell, sec ioned o di e en es s.
C ys als 2023,13, 757 4 o 13
3. Resul s and Discussion
3.1. Chemical Composi ion
The chemical composi ion was analysed o all six samples lis ed in Table 2. Figu e 2a
shows he change in chemical composi ion as a unc ion o he p opo ion o sc ap e u ns.
The main alloying elemen s, such as Si, Cu, and Fe, a ied andomly om sample o
sample. In he case o Si, he a ia ion was be ween 7.4 and 8 w %, which was s ill wi hin
he ange o s anda d alues. Simila luc ua ions we e also obse ed o Cu. The eason
o hese di e ences in he alues o Si and Cu was he addi ion o esidues o he base
alloy. The sc ap had di e en shapes and sizes, e.g., he eede sys ems we e ela i ely
la ge, which mean ha solidi ica ion in he eede sys ems du ing p oduc ion o he
cas ings ook place a he lowes cooling a es, esul ing in a coa se and inhomogeneous
mic os uc u e. When cu ing samples om such eede sys ems, he a eas wi h mo e o
less mic os uc u al cons i uen s such as eu ec ic
βSi
and Cu- ich Al
2
Cu and Q-AlCuMgSi
phases we e andomly selec ed, esul ing in di e ences in he Si and Cu alues.
Figu e 2.
(
a
) The chemical composi ion o all samples; (
b
) The amoun s o phases in all samples
p edic ed by CALPHAD calcula ions.
Fo o he alloying elemen s, he si ua ion was a li le di e en . The con en s o some
elemen s ha we e suscep ible o oxida ion we e educed a highe addi ions o sc ap
e u ns. This mean ha he liquid me al used o he cas ing p ocess was kep in a u nace
o a while be o e cas ing, whe e elemen s such as Ca, Mg, and Z we e oxidised. On he
C ys als 2023,13, 757 5 o 13
o he hand, elemen s such as C and Mn could also oxidise o o m phases ha se led on
he bo om o he holding u nace due o he highe densi y o loa in he oxide laye ha
was emo ed be o e cas ing. When he e u n sc ap was emel ed in he p oduc ion o
samples, oxida ion ook place again, esul ing in a u he dec ease in he composi ion o
he elemen s men ioned.
In con as , he con en s o some elemen s we e inc eased. These elemen s we e B,
Bi, Sn, S , Ni, Pb, Ti, and Zn. These elemen s we e mo e s able and did no oxidise in
he mel . Ti, B, and S a e added o he mel wi h he in en ion o e ining he g ain and
modi ying he mel . F om he i s sample (226-100) o he las , which had 100% sc ap
e u n con en (226-00), he con en s o Ti, B, and S we e inc eased by 14%, 50%, and as
much as 66%, espec i ely.
3.2. CALPHAD Simula ions
The esul o he CALPHAD calcula ions was an isople h phase diag am, as shown o
sample 226-100 in Figu e 3a. I showed he solidi ica ion pa h o an alloy in which solidi i-
ca ion s a ed wi h he
αAl
phase, ollowed by Al15Si2M4, he i on- ich
α
-Al
15
(Fe,Mn)
3
Si
2
phase. Ano he i on- ich phase, Al
9
Fe
2
Si
2
, solidi ied nex , also e e ed o as Al
5
FeSi and
ma ked as
β
-AlFeSi [
19
]. Solidi ica ion p oceeded wi h he main eu ec ic (
αAl
+
βSi
) phase
in which solidi ica ion should end. Acco ding o he calcula ions, p ecipi a ion occu ed in
he Q-Al
5
Cu
2
Mg
8
Si
6
phase, which is also e e ed o as Q-AlCuMgSi. The nex phase o
p ecipi a e was Al
2
Cu and he low- empe a u e Si
2
S phase. Figu e 3b–e shows he plo s o
phase ac ions e sus empe a u e o samples 226-100 and 226-00. The phase ac ions
we e sligh ly di e en in he wo alloys, bu di e ences we e also obse ed in he empe a-
u e anges o solidi ica ion and p ecipi a ion o he phases and in he o de o solidi ica ion
o he i on- ich phases. In he i s sample, he i on- ich
α
-Al
15
(Fe,Mn)
3
Si
2
phase solidi ied
i s , ollowed by
β
-AlFeSi, bu in sample 226-00, i was he o he way a ound due o he
di e en chemical composi ion. Figu e 2b shows he calcula ed phase ac ions o all
samples and i can be seen ha ac ions o
α
-Al
15
(Fe,Mn)
3
Si
2
and Q-AlCuMgSi dec eased
as he amoun o sc ap e u ns in he alloy inc eased due o he lowe con en o Mn and
Mg in he samples.
The Scheil model o solidi ica ion o all samples is shown in Figu e 4. The p edic ed
solidi ica ion pa h was simila o ha desc ibed abo e, wi h he di e ence being ha he
Cu-con aining phases solidi ied a he end o he solidi ica ion ange and did no p ecipi a e
ou o he solid. The di e ence in he solidi ica ion o he Cu- ich Q-AlCuMgSi and Al
2
Cu
phases was e iden in he second sample (226-80), which con ained 20% sc ap e u ns. In
he sample wi hou sc ap e u ns (266-100), Q-AlCuMgSi solidi ied i s and hen Al
2
Cu,
bu he o de was e e sed in sample 226-80, so ha Al
2
Cu solidi ied be o e Q-AlCuMgSi.
The eason o his mus ha e been he lowe Mg con en and di e en Cu con en , as
men ioned abo e. Simila ly, he e was ano he change in he o de o solidi ica ion o
Fe-bea ing phases, as desc ibed in he equilib ium isople h phase diag am. In samples
226-100 o 226-40, he i s o he i on phases o solidi y was
α
-Al
15
(Fe, Mn)
3
Si
2
and he
second was
β
-AlFeSi, bu he o de o solidi ica ion changed in he samples con aining
mo e han 80% sc ap e u ns (226-20 and 226-00). I can also be seen ha a e he main
eu ec ic (
αAl
+
βSi
) solidi ica ion ended, he
β
-AlFeSi phase disappea ed. Figu e 4shows
he p esence o he AlB
2
, Al
3
Ti, and Si
2
S phases. The eason o his was ha B, Ti, and S
we e also included in he calcula ions, esul ing in he a o emen ioned phases. The es o
he solidi ica ion was una ec ed and he phases we e no he objec o he s udy.
3.3. The mal Analysis
The mal analysis was ca ied ou o all six samples. Figu e 5shows he cooling cu es
and de i a i es o samples 266-100 and 266-00, espec i ely. All cooling cu es showed
simila beha iou s. The di e ences in all cha ac e is ic empe a u es we e ela i ely small,
e.g., he liquid empe a u e anged be ween 594.1
◦
C and 595.3
◦
C. Highe di e ences we e
ound in he main eu ec ic egion and he second eu ec ic egion, eaching up o 5.5
◦
C

C ys als 2023,13, 757 6 o 13
di e ence. The de i a i e cu es o all samples we e also simila , excep ha he las peak
changed wi h highe addi ions o sc ap e u ns and spli in o wo peaks. I was assumed
ha he eason o his was he changed o de o solidi ica ion o he Cu- ich phases and
he lowe amoun o he Q-AlCuMgSi phase.
Figu e 3.
(
a
) Isople h phase diag am o sample 226-100; (
b
) Phase ac ion e sus empe a u e o
sample 226-100; (
c
) Magni ica ion o (
b
); (
d
) Phase ac ion e sus empe a u e o sample 226-00;
(e) Magni ica ion o (d).
C ys als 2023,13, 757 7 o 13
C ys als 2023, 13, x FOR PEER REVIEW 7 o 13
Figu e 4. Scheil model o solidi ica ion o : (a) Sample 226-100; (b) Sample 226-80; (c) Sample 226-60;
(d) Sample 226-440; (e) Sample 226-20; ( ) Sample 226-00.
3.3. The mal Analysis
The mal analysis was ca ied ou o all six samples. Figu e 5 shows he cooling
cu es and de i a i es o samples 266-100 and 266-00, espec i ely. All cooling cu es
showed simila beha iou s. The di e ences in all cha ac e is ic empe a u es we e ela-
i ely small, e.g., he liquid empe a u e anged be ween 594.1 °C and 595.3 °C. Highe
di e ences we e ound in he main eu ec ic egion and he second eu ec ic egion, each-
ing up o 5.5 °C di e ence. The de i a i e cu es o all samples we e also simila , excep
ha he las peak changed wi h highe addi ions o sc ap e u ns and spli in o wo peaks.
I was assumed ha he eason o his was he changed o de o solidi ica ion o he Cu-
ich phases and he lowe amoun o he Q-AlCuMgSi phase.
Figu e 4.
Scheil model o solidi ica ion o : (
a
) Sample 226-100; (
b
) Sample 226-80; (
c
) Sample 226-60;
(d) Sample 226-440; (e) Sample 226-20; ( ) Sample 226-00.
3.4. Me allog aphy
•SEM
SEM mic og aphs a e shown in Figu e 6wi h he co esponding EDS analyses. The
same mic os uc u al cons i uen s we e de e mined in all six samples, only he ac ions
we e changed, as shown below. Figu e 6a shows phases such as
αAl
-ma ix,
βSi
,
α
-Al
15
(Fe,
Mn)
3
Si
2
,
β
-AlFeSi, and Al
2
Cu wi h he co esponding EDS analyses in Table 3. Figu e 6b
shows he Cu-con aining Al
2
Cu and Q-AlCuMgSi phases and a hea y phase ich in Pb,
Sn, and Ca, which was mos p obably oxidised since he amoun o oxygen was ela i ely
high. An addi ional Al
2
S Si
2
phase was de e mined as a esul o S en ichmen . The ac ual
composi ions o he phases de e mined by he EDS analyses (Table 3) we e no exac bu
C ys als 2023,13, 757 8 o 13
a ied in elemen s and Al was p esen in almos all measu emen s. This was due o he
na u e o he analysis, which also analysed he backg ound o he sample. The phases we e
de e mined on he basis o EDS analyses and p e ious epo s [17,18,20–23].
C ys als 2023, 13, x FOR PEER REVIEW 8 o 13
Figu e 5. Cooling cu e and i s de i a i e o samples (a) 226-100; (b) 226-00.
3.4. Me allog aphy
•SEM
SEM mic og aphs a e shown in Figu e 6 wi h he co esponding EDS analyses. The
same mic os uc u al cons i uen s we e de e mined in all six samples, only he ac ions
we e changed, as shown below. Figu e 6a shows phases such as αAl-ma ix, βSi, α-Al15(Fe,
Mn)3Si2, β-AlFeSi, and Al2Cu wi h he co esponding EDS analyses in Table 3. Figu e 6b
shows he Cu-con aining Al2Cu and Q-AlCuMgSi phases and a hea y phase ich in Pb,
Sn, and Ca, which was mos p obably oxidised since he amoun o oxygen was ela i ely
high. An addi ional Al2S Si2 phase was de e mined as a esul o S en ichmen . The ac ual
composi ions o he phases de e mined by he EDS analyses (Table 3) we e no exac bu
a ied in elemen s and Al was p esen in almos all measu emen s. This was due o he
na u e o he analysis, which also analysed he backg ound o he sample. The phases
we e de e mined on he basis o EDS analyses and p e ious epo s [17,18,20–23].
Figu e 5. Cooling cu e and i s de i a i e o samples (a) 226-100; (b) 226-00.
Figu e 6.
SEM mic og aphs wi h ma ked spo s o EDS analyses: (
a
) Sample 226-00; (
b
) Sample
226-100; (c) Sample 226-20.
•Op ic me allog aphy
Op ical me allog aphy showed simila esul s o SEM, bu some phases and hei
dis ibu ions we e clea ly isible in he op ical mic og aphs. Figu e 7shows op ic mic o-
g aphs o all six samples a lowe magni ica ion. The g een and ed a ows show he Fe- ich
phases. The g een a ows show he Al
15
(Fe, Mn)
3
Si
2
phases, which we e in he o m o
Chinese sc ip , and he ed a ows show he needle-like
β
-AlFeSi phases. In he sample
C ys als 2023,13, 757 9 o 13
wi hou sc ap e u ns he e we e no needle-like phases, bu as he con en o sc ap e u ns
in he samples inc eased, he needle-like phases appea ed and he p opo ions became
highe due o di e en Mn:Fe a ios as he Mn con en dec eased. Ve y ew needle-like
phases appea ed in samples 226-100 and 226-80, bu he i s ep esen a i e needle-like
phase appea ed in sample 226-60, in which he Mn:Fe a io was 0.38, and he amoun o he
phase inc eased as he a io was u he dec eased o 0.30 in sample 226-00. Table 4shows
he esul s o he numbe and measu ed a eas o he needle-like phase on wo mic og aphs
o each sample. In samples 226-100 and 226-80, 7 and 5 needles we e ound, espec i ely,
bu he numbe o needles inc eased o mo e han 30 in samples wi h highe amoun s
o ound y sc ap e u ns. Table 4also shows he a ea pe cen ages o he needle-shaped
phase in he samples. I can be seen ha he amoun inc eased om 0.11 a ea pe cen
in sample 226-100 o 0.69 a ea pe cen in sample 226-00. The Chinese sc ip -like Al
15
(Fe,
Mn)
3
Si
2
phase did no show he dec easing end as would be expec ed due o he inho-
mogeneous dis ibu ion o phases in he mic os uc u e and he phases we e no cap u ed
ep esen a i ely in he op ic mic og aphs.
Table 3. EDS analyses in a % and de e mined phases om Figu e 6.
·Phase O Al Si C Mn Fe Cu Zn Mg Ca Sn Pb S
1 Al2Cu 1.8 63.8 1.5 ···32.9 ······
2α-Al15(Fe, Mn)3Si2·70.1 11.8 1.0 4.4 11.0 1.6 ······
3β-AlFeSi ·65.1 20.8 ·1.5 12.7 ·······
4αAl-ma ix ·97.7 1.5 ···0.5 0.3 ·····
5βSi ·27.6 72.1 ···0.2 ······
6 Pb- ich phase 41.9 11.1 4.7 ···2.9 · · 2.3 3.2 29.8 ·
7 Al2Cu 1.3 19.7 31.2 ···10.9 ·4.2 · · · ·
8 Q-AlCuMgSi 1.2 78.6 1.1 ···19.1 ·36.9 · · · ·
9 Al2S Si22.1 31.8 52.9 ······0.7 · · 12.6
10 Pb- ich phase ·6.9 91.1 ·····0.6 ·0.5 0.5 0.5
11 βSi ·5.4 94.6 ··········
Table 4. The numbe and amoun o needle-like β-AlFeSi phase in all samples.
Sample Designa ion A ea/µm2A ea% No.
226-100 628.4054 0.109109 7
226-80 681.3081 0.118121 5
226-60 732.128 0.123589 11
226-40 2630.312 0.457297 31
226-20 2697.656 0.468391 32
226-00 4003.538 0.690667 33
3.5. Mechanical P ope ies
•Tensile es s
Thi y- i e days a e cas ing he samples, he ou specimens o each alloy sample
unde wen ensile es ing. Acco ding o he s anda d SIST EN ISO 6892-1 A224, he ensile
s eng h (Rm), yield s eng h (R
p0.2
), elonga ion (A), and modulus o elas ici y (E) we e
de e mined. The a e age alues we e calcula ed om ou measu emen s and a e shown
g aphically in Figu e 8a. In addi ion, linea co ela ions we e calcula ed, as shown in
Figu e 8a. I can be seen ha all o he measu ed p ope ies dec eased wi h inc easing
amoun s o sc ap ma e ial, excep o a sligh inc ease in elonga ion, bu he sca e o he
esul s was ela i ely la ge so he inc ease was insigni ican . The dec ease in all measu ed