Welding of Advanced High Strength Steels for Automotive Applications


Hello friends, welcome to the introduction
to the course welding of advanced high strength steels for automotive applications. We know that advanced high strength steels
are increasingly used in automotive industry to achieve light weighting and to improve
cross performance. These steels possess high strength and acceptable
ductility which makes them very attractive candidates to replaces conventionally used
steels. The improvement in strength and ductility
combinations which is you know not possible in conventional steel is achieved by their
complex multiphase microstructures of advanced high strength steels. We stabilize these microstructures by some
unconventional heat treatment thermomechanical processing and adding certain alignment, which
are not present in conventional automotive steels. However, the alignments we add to stabilize
the microstructures severely affect the weldability and the thermal cycle of the welding process
also destroys the carefully designed multiphase microstructure of the steels. Thereby the commercial applicability of the
steels is considered to be limited or find difficult. In order to use these steels therefore we
need to understand their welding behaviour. In this course, we designed to give an overview
of the physical and welding metallurgy of advanced high strength steels and what are
the problems we may face during welding of these steels. We divided this course into 4 parts, each
part running roughly a week. Okay where in the first part we would like
to give an introduction to advanced high strength steels and their production methodology and
their physical metallurgy of the steels. In second part, we are aiming to give an introduction
to the welding processor that are generally used in automotive industry such as an advance
GMAW particularly the gas metal arc welding with the special emphasis on cold metal transfer
welding and the most commonly used welding process such as resistance spot welding and
laser beam welding. In the third part, we will discuss the welding
behavior of advanced high strength steels mainly to how the typical weld thermal cycle
is changing the base metal microstructures in the fusion zones. And the heat affected zone and then we will
move to the final part which is actually designed to give an overview of the mechanical properties
of advanced high strength steels elements and what are the problems that are present
in the heat affected zone and the fusion zone of the advanced high strength welds and what
are the suitable welding methodologies can be adopted to improve the weldability of this
steels. Therefore, this course gives the entire overview
of the physical and welding metallurgy of advanced high strength steels. Who can attend this course: Engineers working
in automotive industries and steel plants and who are directly dealing advanced high
strength steels for commercial applications, the final year under graduate students or
the students in the first year masters course in metallurgical, mechanical, and production
engineering? For other course details please visit the
course home page in NPTEL page. I welcome you all for this course. Thank you.