FRICTION STIR WELDING is latest & green technology of welding.

1. FRICTION
STIR
WELDING
PREPARED BY:- NAVED HASAN KHAN B.Tech 5th sem IPE
Co-founder- udaan welfare foundation navedhasankhn8@gmail.com

2. WELDING PROCESS
 Welding is a process of joining of different or similar
material.
 Advantages
economical
considerable freedom in designing
large no. of dissimilar or similar materials
joined
weld as strong as the parent metal

3. HISTORY :-
 Friction stir welding was invented by The Welding
Institute (TWI) in December 1991.
 TWI filed successfully for patents in Europe, the
U.S.A. , Japan, and Australia.
 TWI then established TWI Group-Sponsored
Project 5651,"Development of the New Friction
Stir Technique for Welding Aluminum," in 1992 to
further study this technique.

4. Tools used for Friction Stir Welding
 High speed steel is used for welding aluminium
 For welding steel and tungsten alloys tungsten and iridium alloy
based tool is used.

5. HOW DOES IT WORK ???
 Friction stir welding is a new solid state joining process.
 Here a cylindrical shouldered tool along with a profiled probe is
rotated and fed at a constant traverse rate in to the joint.
 Frictional heat generated between the wear resistant welding
tool and the workpiece along with mechanical mixing heat causes
the stirred material to soften without reaching the melting point
and allows the traversing of the tool along the weld line.
 The plasticized material is transferred from the leading edge of
the tool to its trailing edge and is forged by the intimate contact
of the tool shoulder and the pin profile thus leaving a solid bond
between two phases.

6. Schematic diagram of the FSW process
Two discrete metal workpieces butted together, along
with the tool (with a probe).
The progress of the tool through the joint, also showing
the weld zone and the region affected by the tool
shoulder.

7. Schematic diagram of the FSW process (contd.)

8. Microstructure classification of friction
stir welding:-
A. Unaffected material
B. Heat affected zone (HAZ)
C. Thermo-mechanically affected zone (TMAZ)
D. Weld nugget (Part of thermo-mechanically affected zone)

10. Materials and thickness
Friction stir welding can be used for joining
2000, 5000,6000,7000 series aluminum.
Aluminium based metal matrix composites
Copper and its alloys (up to 50mm in one pass).
Titanium and its alloys.
Zinc, plastic, stainless steel and nickel alloys.

11. Friction stir welding of Ti and steel alloys

12. Applications of friction stir welding
1. Ship building and marine industries
 Panels for decks, bulk heads and floors
 Hulls and superstructures
 Helicopter landing platforms
 Mast and booms (sailing boat)

13. Applications of friction stir welding (contd.)
2. Aerospace industry
 Fuel tank for space vehicles
 Aviation fuel tanks
 Military and scientific
rockets
 Various primary and
secondary structural
component

14. Applications of friction stir welding (contd.)
3. Railway and land transport.
 High speed trains
 Railway tankers and goods wagon
 Wheel rims
 Motor cycle and bicycle frames

15. ADVANTAGES
 Good mechanical properties in the as welded condition.
 Improved safety due to the absence of toxic fumes or the spatter of molten
material.
 No consumables - conventional steel tools can weld over 1000m of aluminum
and no filler or gas shield is required for aluminum.
 Easily automated on simple milling machines - lower setup costs and less
training.
 Can operate in all positions (horizontal, vertical, etc), as there is no weld pool.
 Generally good weld appearance and minimal thickness under/over-
matching, thus reducing the need for expensive machining after welding.
 Low environmental impact.

16. DISADVANTAGES
 Workpieces must be rigidly clamped
 Backing bar required (except for self reacting and
directly opposed tools)
 Key holes at the end of each weld
 Cannot make joints that require metal deposition
 Less flexible than manual and arc processes

17. Conclusion
 New technology with vital application in aerospace an
marine
 Presently limited to aluminum ,its alloys and related
metals
 FSW of steel and titanium alloys are developed and
they are in the nascent stage
 Will emerge as a better welding technology