Applicability of Bobbin Tool Friction Stir
Welding for Dissimilar Al-Mg Joint
Harshadkumar H. Jadav, Vishvesh J. Badheka, Kishan Fuse, Kush Mehta,
and Gautam Upadhyay
Abstract Stringent material property demand for fuel economy in automobile and
aerospace industry can be addressed only by either reducing weight or improving efficiency of the engine. Structural weight reduction requires dissimilar materials with
varying thickness and geometry to be joined. Friction stir welding (FSW) is one of the
latest additions to the joining processes. Bobbin tool friction stir welding (BTFSW)
is a novel derivative of FSW process utilizing two shoulders for even heat distribution
with advantage of eliminating backup support. This paper reports conventional FSW
and feasibility trials of BTFSW for similar aluminum alloy (AA6061-T6), similar
magnesium alloy (AZ31B) and dissimilar aluminum alloy (AA6061-T6) to magnesium alloy (AZ31B). Conventional FSW trials report successful welds without any
observable surface defects. However, BTFSW weld surface presents defects like flash
and groove, and material sticking to the tool pin is observed. Pin length, bigger diameter of the lower shoulder and flat surface of tool shoulder without chamfered edge are
considered to be responsible for flash and groove defects. Process parameters which
could have restricted joint formation are discussed. Though these feasibility trials
of dissimilar aluminum and magnesium alloy BTFSW achieved limited success, it
paves a path for successful joining using BTFSW.
Keywords Bobbin tool FSW · Dissimilar welding · Magnesium alloy · Aluminum
alloy
H. H. Jadav (B)
Government Engineering College, Sector 28, Gandhinagar 382028, India
e-mail: harsshad75@gmail.com
H. H. Jadav · G. Upadhyay
Gujarat Technological University, Ahmedabad 382424, India
V. J. Badheka · K. Fuse · K. Mehta
Pandit Deendayal Petroleum University, Gandhinagar 382007, India
© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2021
A. K. Parwani et al. (eds.), Recent Advances in Mechanical Infrastructure,
Lecture Notes in Intelligent Transportation and Infrastructure,
https://doi.org/10.1007/978-981-33-4176-0_18
223
Welding for Dissimilar Al-Mg Joint
Harshadkumar H. Jadav, Vishvesh J. Badheka, Kishan Fuse, Kush Mehta,
and Gautam Upadhyay
Abstract Stringent material property demand for fuel economy in automobile and
aerospace industry can be addressed only by either reducing weight or improving efficiency of the engine. Structural weight reduction requires dissimilar materials with
varying thickness and geometry to be joined. Friction stir welding (FSW) is one of the
latest additions to the joining processes. Bobbin tool friction stir welding (BTFSW)
is a novel derivative of FSW process utilizing two shoulders for even heat distribution
with advantage of eliminating backup support. This paper reports conventional FSW
and feasibility trials of BTFSW for similar aluminum alloy (AA6061-T6), similar
magnesium alloy (AZ31B) and dissimilar aluminum alloy (AA6061-T6) to magnesium alloy (AZ31B). Conventional FSW trials report successful welds without any
observable surface defects. However, BTFSW weld surface presents defects like flash
and groove, and material sticking to the tool pin is observed. Pin length, bigger diameter of the lower shoulder and flat surface of tool shoulder without chamfered edge are
considered to be responsible for flash and groove defects. Process parameters which
could have restricted joint formation are discussed. Though these feasibility trials
of dissimilar aluminum and magnesium alloy BTFSW achieved limited success, it
paves a path for successful joining using BTFSW.
Keywords Bobbin tool FSW · Dissimilar welding · Magnesium alloy · Aluminum
alloy
H. H. Jadav (B)
Government Engineering College, Sector 28, Gandhinagar 382028, India
e-mail: harsshad75@gmail.com
H. H. Jadav · G. Upadhyay
Gujarat Technological University, Ahmedabad 382424, India
V. J. Badheka · K. Fuse · K. Mehta
Pandit Deendayal Petroleum University, Gandhinagar 382007, India
© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2021
A. K. Parwani et al. (eds.), Recent Advances in Mechanical Infrastructure,
Lecture Notes in Intelligent Transportation and Infrastructure,
https://doi.org/10.1007/978-981-33-4176-0_18
223