Dissimilar Metal Welding
description
Transcript of Dissimilar Metal Welding
M.Ekaditya Albar 1106154305
Rangga Agung 1106108942
Rhidiyan Waroko 0806331935
Rudiyansah 0806331973
Master Degree Program
Metallurgy and Material Engineering Department
Universitas Indonesia
7-Jan-13 1
Outline
Dissimilar Metal Welding
Journal Review
Enhanced mechanical properties of friction stir welded dissimilar Al–Cu
joint by intermetallic compounds
Dissimilar friction welding of induction surface-hardened steels and
thermochemically treated steels
Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy
Weldability and mechanical properties of dissimilar aluminum–copper lap
joints made by friction stir welding
7-Jan-13 2
Dissimilar Metal Welding
The joining of dissimilar materials is becoming increasingly
important in industrial applications due to their numerous
advantages. These include not only technical advantages, such as
desired product properties, but also benefits in terms of production
economics.
Dissimilar metals are difficult to join with conventional fusion
welding due to their different chemical and physical
characteristics, thus solid state joining methods have received
much attention.
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Journal 1: Enhanced mechanical properties of friction stir welded dissimilar Al–Cu
joint by intermetallic compounds (May 2010)
7-Jan-13 4
Introduction:
FSW has been shown to be an effective way of joining materials with poor fusion weldability, such as
high-strength aluminum alloys and magnesium alloys.
In Al-Cu joints, an intermetallic compound (IMC) layer usually formed on the Al–Cu interface.
IMCs were easily formed in the nugget zone due to severe plastic deformation and thermal exposure.
IMCs have been used as reinforcing particles in metal matrix composites (MMCs).
Control of the IMC layer between dissimilar metals and the size and distribution of the IMC particles in the
nugget zone becomes a key factor for FSW of dissimilar metals.
Experiment:
1060 Aluminum + Pure Copper (99.9%) Plate (p x l x t : 300 x 70 x 5 mm)
FSW machine (China FSW Center)
Tool traverse speed : 100 mm min−1 ; Rotation rate : 600 rpm
Microstructural Analysis : EPMA, XRD, SEM, TEM, EDS
Mechanical Testing : Tensile Test, Vickers Microhardness, Three-point Bending Test
Results and Discussions:
The nugget zone consists of a mixture of the aluminum matrix and Cu particles.
A continuous and uniform interface layer is formed with a thickness of ∼1 μm.
Reinforcing particles were mainly composed of Al2Cu, Al4Cu9, and few AlCu particles.
UTS of the composite structure was as high as 210 MPa.
The hardness increased substantially due to the strengthening effect of the Al–Cu IMC particles.
SEM
Re
sult
PRZ
Journal 1: Enhanced mechanical properties of friction stir welded dissimilar Al–Cu
joint by intermetallic compounds (May 2010)
7-Jan-13 5
XR
D R
esu
lt
EPMA Result
Journal 1: Enhanced mechanical properties of friction stir welded dissimilar Al–Cu
joint by intermetallic compounds (May 2010)
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Hardness Vickers Te
nsi
le T
est
TEM Result
Journal 1: Enhanced mechanical properties of friction stir welded dissimilar Al–Cu
joint by intermetallic compounds (May 2010)
7-Jan-13 7
Bending Test
Conclusions:
1060 aluminum alloy and commercial pure copper were successfully friction stir welded.
Reinforcing particles were mainly composed of Al2Cu, Al4Cu9, and few AlCu particles.
UTS of the composite structure was as high as 210 MPa.
The hardness increased substantially due to the strengthening effect of the Al–Cu IMC particles.
Bending without fracture was generated at the Al–Cu interface.
Journal 2: Dissimilar friction welding of induction surface-hardened steels and
thermochemically treated steels (April 2012)
7-Jan-13 8
Background:
Friction welding is a highly productive process that relies on the conversion of mechanical energy into
thermal energy.
For friction joining of surface hardened steels, the distribution of the thermal gradient on the surfaces in
contact during the process is affecting the hardness at the interface.
This work is focused on the particularities of the conventional friction welding process of dissimilar steels for
joints in which one component is induction-hardened, using high frequency currents, and the other one is
subject to another heat or thermochemical treatment, such as carburization or nitriding.
Experiment:
Hardness test (HVS – 10A1 hardness tester on longitudinal section, polished and nital-etch join)
Macroscopic (Olympus SZH-10 stereo microscope)
Microstructure (Olympus BH-2 metallographic microscope)
Bending test (Instron 250 kN universal testing machine)
Torsion test (Schenk-Trebel torsion testing machine 1600Nm)
Impact test (V-Notched, 300 J Charpy pendulum)
Journal 2: Dissimilar friction welding of induction surface-hardened steels and
thermochemically treated steels (April 2012)
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Steel C Mn Si P S Cr Mo Ni
C45 0.48 0.63 0.25 0.029 0.028 - - -
C55 0.56 0.61 0.27 0.028 0.024 - - -
16MnCr5 0.17 1.14 0.31 0.025 0.026 1.07 - -
34CrNiMo6 0.36 0.61 0.28 0.027 0.027 1.52 0.24 1.54
Materials
Journal 2: Dissimilar friction welding of induction surface-hardened steels and
thermochemically treated steels (April 2012)
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Treatments
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Fig. 1. Hardness gradient
of the C55 steel after high
frequency induction-
hardening Fig. 2. Macro and micrographic images of the dissimilar C55 induction-
hardened with a C45 quench-hardened steel friction welded joint
Fig. 3. Hardness gradients for two values of the friction/upsetting pressure across the joining plane for the
dissimilar C45 quench-hardened-C55 induction-hardened friction welded joint, measured in the marginal and
central areas, respectively
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Fig. 6. Hardness gradients in axial direction
across the joint plane for the induction-hardened
34CrNiMo6 steel with a 16MnCr5 carburized-
quenched-tempered steel joint for two values of
the friction/forging pressure.
Fig. 5. Macro and microscopic images of the friction
welded joints of induction-hardened 34CrNiMo6 and
16MnCr5 carburized-quenched-tempered steels.
Fig. 4. Details about the microstructure and hardness gradients
in pre-welding state for the 16MnCr5 (carburized) and
34CrNiMo6 (induction-hardened) steels used in the experiments.
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Fig. 7. Typical microstructure and hardness gradient
observed for the C45 after the nitriding operation and
the macroscopic image of the C55 induction-
hardened and C45 nitrided steel joint.
Results and Discussions:
A biconcave HAZ forms for high
friction/forging pressures
(300/400 N/mm2), if one of the
components is thermomechanically
treated.
The decrease of the pressure did not
affect the process, neither the extent of
the softening area.
The nitride layer contributes to the
reduction of the relative friction
between the components in the vicinity of
the rotational axis.
The experimental results show that a
high quality joint can only be obtained if
the nitride layer is fully expunged from
the joint plane.
If such nitride debris are still present, a
quasi-cleavage fracture occurs due to
the high cooling rate during the
friction welding process, as also
observed for other combinations with
nitrided steels.
Journal 2: Dissimilar friction welding of induction surface-hardened steels and
thermochemically treated steels (April 2012)
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Conclusions:
The friction pressure is limited to about 200 N/mm2, since higher values were
observed to lead only to minor reduction of the hardness on the induction-
hardened surface and can favor the presence of discontinuities in the center of the
joint plane.
Influenced by the presence hard layers in the join plane.
By increasing the axial pressure, the thermochemically hardened layer can be
expunged in the burr.
The presence of the nitride layer contributes to the reduction of the friction in
the vicinity of the rotational axis.
Regardless of the friction/forging pressures used (200/300 or 300/400 N/mm2) the
joints showed good mechanical properties, but the complete expulsion of the
nitride layer was observed only for 6 mm upset length.
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
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Background:
Al alloy (combination between mass reduction and high strength); Mg alloy (low density and high specific
strength).
Joining Al alloy and Mg alloy will be difficult if we use conventional fusion welding because of large
intermetallic compounds.
FSW is a potential candidate for dissimilar welding because of lower processing temperature and can
produced defect-free weld, i.e. joining Al 2024/Al 7075, Al/steel, Al/Cu, dan Al/Mg
Experiment:
5052 Al alloy + AZ31 Mg alloy, plate thickness 6 mm.
Surface of plate was grounded using grit paper to remove oxide layer then cleaned by ethanol.
5052 Al alloy (advancing side) and AZ31 Mg alloy (retreating side) from tool pin in FSW process.
FSW machine using FSW-3LM-003, vrot = 600 r/min and vwelding = 40 mm/min.
Butt join was resulted parallel to rolling path direction.
Microstructure analysis at cross section of weld direction by OM (KEYENCE VHX-600) and SEM (Quata200)
Etch solution: picric acid (4,2 g), acetic acid (8 ml), distilled water (10 ml), ethanol (70 ml).
Hardness measurement by HVS-100 digit hardness tester, load ! N, dwell time 20 sec.
Materials
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
7-Jan-13 16
Defect-free using FSW (vrot = 600 r/min, vwelding = 40 mm/min).
Interface Mg alloy + Al alloy
Fig. 1. Surface appearance of dissimilar weld prepared by
FSW
Fig. 2. Optical approach of cross-section of dissimilar weld
Defect-free
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
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In Fig. 2 we can see typical microstructural zone, like Base Material (BM),
Heat-Affected Zone (HAZ), Thermomechanical Affected Zone (TMAZ), and
Stir-Zone (SZ).
Fig. 2. Optical approach of cross-section of dissimilar
weld
Simple bond interface
Intermixed structure
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
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Fig. 3. SEM images of AZ31 in different
regions, marked with letters in Fig.2:
(a) BM; (b) HAZ;
(c) Interface of TMAZ/SZ;
(d) SZ in Mg side;
(e) SZ in Al side;
(f) Intercalated microstructure.
Fig. 2. Optical approach of cross-
section of dissimilar weld
BM terdiri dari large equiaxed grains
(50 μm) dan fine grains (10 μm).
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
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Fig. 3. SEM images of AZ31 in different
regions, marked with letters in Fig.2:
(a) BM;
(b) HAZ; (c) Interface of TMAZ/SZ;
(d) SZ in Mg side;
(e) SZ in Al side;
(f) Intercalated microstructure.
Fig. 2. Optical approach of cross-section
of dissimilar weld
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
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Fig. 3. SEM images of AZ31 in different
regions, marked with letters in Fig.2:
(a) BM; (b) HAZ;
(c) Interface of TMAZ/SZ; (d) SZ in Mg side;
(e) SZ in Al side;
(f) Intercalated microstructure.
Fig. 2. Optical approach of cross-section
of dissimilar weld
Dynamic rekristalisasi terjadi di SZ
dikarenakan deformasi plastis dan efek
termal siklik yang disebabkan rotational
tool.
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
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Fig. 3. SEM images of AZ31 in different
regions, marked with letters in Fig.2:
(a) BM; (b) HAZ;
(c) Interface of TMAZ/SZ;
(d) SZ in Mg side; (e) SZ in Al side;
(f) Intercalated microstructure.
Fig. 2. Optical approach of cross-section
of dissimilar weld
Grain dengan ukuran rata-rata 5,4 μm
(daerah d / sisi Mg) dimana lebih kecil
dibandingkan BM.
Fine equiaxed rekristalisasi grains
menghasilkan struktur yang berbeda pada
lokasi yang berbeda dari SZ, seperti pada
daerah d, e, f. (Fig. 2)
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
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Fig. 3. SEM images of AZ31 in different
regions, marked with letters in Fig.2:
(a) BM; (b) HAZ;
(c) Interface of TMAZ/SZ;
(d) SZ in Mg side;
(e) SZ in Al side; (f) Intercalated microstructure.
Fig. 2. Optical approach of cross-section
of dissimilar weld
Grain dengan ukuran rata-rata 6,9 μm
(daerah d / sisi Al) dimana lebih kecil
dibandingkan BM.
Fine equiaxed rekristalisasi grains
menghasilkan struktur yang berbeda pada
lokasi yang berbeda dari SZ, seperti pada
daerah d, e, f. (Fig. 2)
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
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Fig. 3. SEM images of AZ31 in different
regions, marked with letters in Fig.2:
(a) BM; (b) HAZ;
(c) Interface of TMAZ/SZ;
(d) SZ in Mg side;
(e) SZ in Al side;
(f) Intercalated microstructure.
Fig. 2. Optical approach of cross-section
of dissimilar weld
Struktur interkalasi terbentuk dan
ukuran grains rata-rata dari AZ31
Mg alloy (2,8 μm)
Fine equiaxed rekristalisasi grains
menghasilkan struktur yang berbeda pada
lokasi yang berbeda dari SZ, seperti pada
daerah d, e, f. (Fig. 2)
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
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Fig. 2. Optical approach of cross-section of dissimilar weld
Fig. 4. Microstructures of onion ring in dissimilar weld:
(a) Optical microstructure; (b) EDS maps of Mg;
(c) EDS maps of Al;
(d) Distribution in onion ring.
Fig. 4 (a) menunjukkan mikrostruktur terdiri dari
dua pita dengan beda kontras.
Menurut hasil analisis EDX, pita gelap (Mg) dan pita putih (Al), dimana mirip onion ring,
namun bentuknya berbeda dari monolitik FSW.
Hal menarik dapat diamati
pada daerah g (Fig. 2)
dimana berlokasi di SZ
dekat sisi 5052 Al alloy dan
dikelilingi oleh Mg alloy.
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
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Fig. 2. Optical approach of cross-section of
dissimilar weld
Fig. 4. Microstructures of onion ring in dissimilar weld:
(a) Optical microstructure;
(b) EDS maps of Mg; (c) EDS maps of Al;
(d) Distribution in onion ring.
Fig. 4 (b) menunjukkan peta EDX dari distribusi Mg pada daerah g.
Hal menarik dapat diamati
pada daerah g (Fig. 2)
dimana berlokasi di SZ
dekat sisi 5052 Al alloy dan
dikelilingi oleh Mg alloy.
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
7-Jan-13 26
Fig. 2. Optical approach of cross-section of
dissimilar weld
Fig. 4. Microstructures of onion ring in dissimilar weld:
(a) Optical microstructure; (b) EDS maps of Mg;
(c) EDS maps of Al; (d) Distribution in onion ring.
Fig. 4 (c) menunjukkan peta EDX dari distribusi Al pada daerah g.
Hal menarik dapat diamati
pada daerah g (Fig. 2)
dimana berlokasi di SZ
dekat sisi 5052 Al alloy dan
dikelilingi oleh Mg alloy.
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
7-Jan-13 27
Fig. 2. Optical approach of cross-section of
dissimilar weld
Hal menarik dapat diamati
pada daerah g (Fig. 2)
dimana berlokasi di SZ
dekat sisi 5052 Al alloy dan
dikelilingi oleh Mg alloy.
Fig. 4. Microstructures of onion ring in dissimilar weld:
(a) Optical microstructure; (b) EDS maps of Mg;
(c) EDS maps of Al;
(d) Distribution in onion ring.
Komposisi kimia : 83% Al + 17 % Mg (mass
fraction), dimana struktur lamella merupakan
komposisi dari pita Al + Mg.
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
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Distribution of Microstructure
Fig. 2 .Optical approach of cross-section of dissimilar weld
o Nilai Vickers microhardness
dari dissimilar weld diukur
sepanjang garis yang ditandai
pada Fig. 2 dimana posisinya
1,5 mm (atas), 3 mm
(tengah), 4,5 mm (bawah)
dari permukaan atas.
o Hasilnya → Fig. 5
Fig. 5. Microhardness profiles of microstructure
from Mg to Al with different locations
Microhardness menunjukkan distribusi tidak seragam.
Hardness SZ > BM.
Nilai maksimum hardness: posisi tengah SZ dimana 2x
lebih besar dari BM.
Struktur onion-ring dan mikrostruktur interkalasi
penyebab variasi tajam hardness di weld zone.
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
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Fig. 6 menunjukkan lokasi patah tarik dan morfologi patahan dari dissimilar weld yang
diuji tegak lurus dari arah welding.
Spesimen uji tarik gagal pada lokasi 2,5 mm dari pusat sambungan pada sisi
advancing. Fig. 6 (a)
Pada lokasi ini, gradien hardness merupakan yang paling tajam, menurut Fig. 5.
Fig. 6 (b) menunjukkan morfologi patahan SEM yang diamati dari arah normal
terhadap permukaan patahan.
Bentuk cleavage-like dapat ditemukan pada permukaan patahan (patah brittle).
Fig. 6. Fracture section of AZ31/5052 dissimilar friction stir weld: (a) Tensile
fracture location; (b) SEM image of fracture surface
Ten
sil
e T
esti
ng
Journal 3: Dissimilar friction stir welding between 5052 aluminum alloy and AZ31
magnesium alloy (January 2010)
7-Jan-13 30
Conclusions:
Sound weld 5052 Al alloy + AZ31 Mg alloy dapat dihasilkan melalui FSW
dengan vrot = 600 r/min dan vwelding = 40 mm/min.
Mikrostruktur BM menjadi bentuk equiaxed dan fine grains pada SZ.
Dimana pada bagian atas SZ, 5052 + AZ31 alloy simply bonded,
sedangkan struktur onion-ring (komposisi pita Al + Mg) terbentuk di
bagian bawah SZ.
Profil microhardness menunjukkan distribusi tidak seragam, dengan nilai
maksimum microhardness SZ dua kali lebih besar dibandingkan BM.
Posisi patahan berada pada jarak 2,5 mm dari pusat sambungan (pada
sisi Al), dimana gradien hardness merupakan yang paling tajam.
Journal 4: Weldability and mechanical properties of dissimilar aluminum–copper
lap joints made by friction stir welding (October 2009)
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Background:
Lap joints of 1060 aluminum alloy and commercially pure copper by FSW
Usually a large void formation, cracks and other distinct defects throughout the weld
Mechanically mixed region in weld nugget consisting Mainly CuAl2, CuAl, and Cu9Al4, brittle nature of the
Inter Metallic Compound (IMC)
The effect of welding speed on interface morphology (lap joint configuration), microstructure, and joint
strength
Lowering the amount of heat in interface may result in limited formation of IMC
Experiment:
Rolled plates of 1060 aluminum alloy (top) and commercially pure copper (bottom) in lap joint
Dimension of sample 20 mm length and 10 mm width and before welding, the samples were degreased using
acetone
Make lap joints, a FSW adapted milling machine was used
The couple samples were friction stir welded with the pin rotating clockwise at speed of 1180 rpm and
welding speeds of 30, 60, 95, 118, 190, 300, and 375 mm/min
Microstructural analysis : Metallographic analysis (OM + SEM + EDS)
Mechanical testing : Tensile Shear Test
Journal 4: Weldability and mechanical properties of dissimilar aluminum–copper
lap joints made by friction stir welding (October 2009)
7-Jan-13 32
Results and Discussions:
Extremely high welding speeds in the present work (300 and 375 mm/min), produced very poor metallic
bonding (higher welding speed caused less vertical transport of interface).
The interface in the central region has moved considerably into the bottom plate. This vertical transport of
interface is attributed to the ring-vortex flow of materials created by pin threads.
In the aluminum close to the Al/Cu interface, a dark area was observed (higher welding speeds, this are a was
limited to a narrower region and extended toward the advancing side of the joints).
Cavity defects which are formed outside the optimum FSW conditions, caused by an insufficient heat input
(with increasing the welding speed, this type of defect is more likely to occur). As a matter of fact, decreasing
the welding speed gives effective influence on the plastic flow and consequently increasing the heat input).
Lowering the amount of heat in interface may result in limited formation of IMC.
Macroscopic overviews of the FSW joint
cross sections at constant tool
rotational speed of 1180 rpm and
welding speeds of (a)30, (b)60, (c)95,
(d)118, and (e)190mm/min
Journal 4: Weldability and mechanical properties of dissimilar aluminum–copper
lap joints made by friction stir welding (October 2009)
7-Jan-13 33
Results and Discussions:
The microstructure of the aluminum stir zone was characterized by the equiaxed fine grains (that the equiaxed
fine grains were formed through the dynamic recrystallization during FSW)
The TMAZ area characterized by elongated grains and layers which is between stir zone and the HAZ areas
Copper particles with irregular shape and inhomogeneous distribution were observed in the aluminum dark
area (copper plate near interface was unable to sustain very large vertical elongation and tore apart into the
small-elongated particles that were found in various places in the dark area)
Microstructures showing different regions of (a) fine equiaxed grains in stir zone of aluminum near Al/Cu
interface,(b) elongated aluminum grains in the TMAZ of advancing side
Journal 4: Weldability and mechanical properties of dissimilar aluminum–copper
lap joints made by friction stir welding (October 2009)
7-Jan-13 34
SEM image of copper particle surrounded by equiaxed
grains of Al 1060 Alloy in the weld nugget for the joint
produced by rotational speed of 1180 rpm and welding speed
of 90 mm/min
The back scattered electron (BSE) image of a coarse particle
existing in the nugget shows as tacked layer structure inside;
the EDS spectra for positions A (light gray layers), B (dark
gray layers), C (white layers) shows possible existence of
Al4Cu9, Al2Cu, and base copper, respectively (welding
condition: 95mm/min, 1180rpm)
Journal 4: Weldability and mechanical properties of dissimilar aluminum–copper
lap joints made by friction stir welding (October 2009)
7-Jan-13 35
The failure loads ranged from 1902 to 2642 N.
One can find that with increasing the welding
speed, failure load increases up to a maximum
value and then decreasing behavior is
appeared. The shear load of the joint is probably
affected by two factors: the amount of
microcracks, and cavity formation.
General tensile fracture surface of a
specimen friction stir welded at
rotational and welding speed of 1180
rpm and 95 mm/min, respectively.
The fracture occurred at the
advancing side of aluminum plate
containing copper fragments (white
colored particles)
Journal 4: Weldability and mechanical properties of dissimilar aluminum–copper
lap joints made by friction stir welding (October 2009)
7-Jan-13 36
Conclusions:
The maximum tensile shear strength has been achieved at welding speed
of 95 mm/min
Due to formation of high amount of micro cracks in the dark area at
welding speeds of 30 and 60 mm/min, the tolerable tensile shear was
lower than that of 95 mm/min
Higher welding speeds of 118 and 190 mm/min, the cavity defects are
produced and again tensile shear strength is decreased in compare with
95 mm/min
Lower welding speed caused more vertical transport, while a higher
welding speed caused less vertical transport on the retreating side
References Ion Mitelea, Victor Budau, Corneliu Craciunescu. Dissimilar friction welding of induction
surface-hardened steels and thermochemically treated steels. Journal of Materials
Processing Technology 212 (2012) 1892–1899.
P. Xue, B.L. Xiao, D.R. Ni, Z.Y. Ma. Enhanced mechanical properties of friction stir
welded dissimilar Al–Cu joint by intermetallic compounds. Materials Science and
Engineering A 527 (2010) 5723–5727.
T. Saeid, A. Abdollah-zadeh, B.Sazgari. Weldability and mechanical properties of
dissimilar aluminum–copper lap joints made by friction stir welding. Journal of Alloys
and Compounds 490 (2010) 652–655.
Yan Yong, Zhang Da-tong, Qiu Cheng, Zhang Wen. Dissimilar friction stir welding
between 5052 aluminum alloy and AZ31 magnesium alloy. Trans. Nonferrous Met. Soc.
China 20 (2010) s619-s623.
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