230
H. H. Jadav et al.
d. Material sticking to tool pin was observed with dissimilar BTFSW. Low feed
speed is associated with pin adhesion and material overflowing as flash, generating defects. At high feed speed, plasticized material flow stress increases and
joint formation becomes difficult [41].
e. Tool offset may play a vital role for dissimilar Al-Mg joining using BTFSW.
4 Conclusions
a. Similar Al-Al, Mg-Mg and dissimilar Al-Mg weld were successfully obtained
with conventional FSW with proper fusion.
b. BTFSW for similar Al-Al formed joint but had a groove on the advancing side.
c. BTFSW for similar Mg-Mg was not able to form the joint. Flash on the retreating
side and lack of fusion on the advancing side was observed.
d. BTFSW for dissimilar Al-Mg at lower speed generated heavy flash on the
top surface. The flash generation on advancing and retreating side might have
restricted joint formation. With increased feed speed, higher flash was formed
and plasticized material flushed from trailing shoulder edge as a ribbon.
e. The limited experiments carried out with BTFSW could not create a satisfactory
weld joint with parameters used in the present experimental work. However,
it suggests the possibility of forming dissimilar Al-Mg weld using BTFSW by
establishing process variable window that is common to similar BTFSW for both
alloys.
Acknowledgements The authors would like to thank the Student Research Program of Office
of Research & Sponsored Program, Pandit Deendayal Petroleum University (PDPU), Gandhinagar, India, for providing necessary support and infrastructure to carry out this work under project
No.: ORSP/R&D/SRP/2019-20/1454/61. The processing of samples was undertaken on a Vertical
Machining Center procured under funding from the Indian Space Research Organisation, Department of Space, Government of India, Bangalore (in collaboration with Space Application Center,
Ahmedabad) under the RESPOND program (Project number-ISRO/RES/4/567/09-10).
References
1. Masoudian A, Tahaei A, Shakiba A, Sharifianjazi F, Mohandesi J (2014) Microstructure and
mechanical properties of friction stir weld of dissimilar AZ31-O magnesium alloy to 6061-T6
aluminum alloy. Trans Nonferrous Met Soc China 24(5):1317–1322
2. Kumar U, Prajapati A, Acharya U, Medhi T, RoyB. Saha S(2020) Welding condition &
microstructure of friction stir welded AA 6061-T6 and AZ31B. Mater Today Proc (in press)
3. Lee K, Kwon E (2014) Microstructure of stir zone in dissimilar friction stir welds of AA6061-T6
and AZ31 alloy sheets. Trans Nonferrous Met Soc China 24(7):2374–2379
4. Verma J, Taiwade R, Reddy C, Khatirkar R (2018) Effect of friction stir welding process
parameters on Mg-AZ31B/Al-AA6061 joints. Mater Manuf Processes 33(3):308–314
H. H. Jadav et al.
d. Material sticking to tool pin was observed with dissimilar BTFSW. Low feed
speed is associated with pin adhesion and material overflowing as flash, generating defects. At high feed speed, plasticized material flow stress increases and
joint formation becomes difficult [41].
e. Tool offset may play a vital role for dissimilar Al-Mg joining using BTFSW.
4 Conclusions
a. Similar Al-Al, Mg-Mg and dissimilar Al-Mg weld were successfully obtained
with conventional FSW with proper fusion.
b. BTFSW for similar Al-Al formed joint but had a groove on the advancing side.
c. BTFSW for similar Mg-Mg was not able to form the joint. Flash on the retreating
side and lack of fusion on the advancing side was observed.
d. BTFSW for dissimilar Al-Mg at lower speed generated heavy flash on the
top surface. The flash generation on advancing and retreating side might have
restricted joint formation. With increased feed speed, higher flash was formed
and plasticized material flushed from trailing shoulder edge as a ribbon.
e. The limited experiments carried out with BTFSW could not create a satisfactory
weld joint with parameters used in the present experimental work. However,
it suggests the possibility of forming dissimilar Al-Mg weld using BTFSW by
establishing process variable window that is common to similar BTFSW for both
alloys.
Acknowledgements The authors would like to thank the Student Research Program of Office
of Research & Sponsored Program, Pandit Deendayal Petroleum University (PDPU), Gandhinagar, India, for providing necessary support and infrastructure to carry out this work under project
No.: ORSP/R&D/SRP/2019-20/1454/61. The processing of samples was undertaken on a Vertical
Machining Center procured under funding from the Indian Space Research Organisation, Department of Space, Government of India, Bangalore (in collaboration with Space Application Center,
Ahmedabad) under the RESPOND program (Project number-ISRO/RES/4/567/09-10).
References
1. Masoudian A, Tahaei A, Shakiba A, Sharifianjazi F, Mohandesi J (2014) Microstructure and
mechanical properties of friction stir weld of dissimilar AZ31-O magnesium alloy to 6061-T6
aluminum alloy. Trans Nonferrous Met Soc China 24(5):1317–1322
2. Kumar U, Prajapati A, Acharya U, Medhi T, RoyB. Saha S(2020) Welding condition &
microstructure of friction stir welded AA 6061-T6 and AZ31B. Mater Today Proc (in press)
3. Lee K, Kwon E (2014) Microstructure of stir zone in dissimilar friction stir welds of AA6061-T6
and AZ31 alloy sheets. Trans Nonferrous Met Soc China 24(7):2374–2379
4. Verma J, Taiwade R, Reddy C, Khatirkar R (2018) Effect of friction stir welding process
parameters on Mg-AZ31B/Al-AA6061 joints. Mater Manuf Processes 33(3):308–314