The document discusses transformation-induced plasticity (TRIP) steels, which are low-alloy steels characterized by a unique microstructure that enhances strength, ductility, and formability. It outlines the composition, processing methods, and mechanical properties of TRIP steels, as well as their applications in automotive structures due to their high energy absorption capacity. The economic advantages of TRIP steels compared to other high-strength materials are also highlighted.

1. TRIP Steel
ansformation Induc
Plasticity - Steel
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
30-01-2015 1
TRIP Steel

2. 30-01-2015 2
INTRODUCTION
•TRIP-aided steels are new generation of low-alloy steel
•Enhanced combination of strength and ductility.
•Triple phase micro structure – Ferrite, bainite and retained
austenite.
•Greater elongation.
•High strain hardening capacity.
•Good formability and drawability.
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
TRIP Steel

3. 30-01-2015 3
COMPOSITION OF TRIP STEEL
•Hypoeutectoid iron carbon alloys.
•0.1 – 0.4 % carbon by weight.
•Alloying elements to prevent high carbon cementite phase,
which raises the carbon concentration of the austenite phase.
•Silicon and Aluminium are two common alloying elements.
•Titanium, Niobium, Vanadium, etc., are other alloying elements
can be added to improve the strength of the alloy.
•Good formability and drawability.
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
TRIP Steel

4. 30-01-2015 4
“TRIP” EFFECT
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
TRIP Steel

5. 30-01-2015 5
PROCESSING METHOD
•Intercritical annealing is used to obtain the correct
phase distribution.
•Temperature above Eutectoid – material is composed of a solid
austenite phase and solid ferrite phase.
•The material is then isothermally cooled at a temperature of
approximately 400 degrees Celsius, in order to allow the austenite
to form a banitic ferrite phase.
•In a typical steel alloy, the excess carbon would form a high
carbon cementite phase. However, the silicon and aluminium
prevent the formation of cementite.
•The result of the intercritical annealing process is a material
composed primarily of ferrite, and bainite. formed from the
austenite phase during intercritical annealing, as well as dispersed
retained austenite, and martensite phases.
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
TRIP Steel

6. 30-01-2015 6
PROCESSING METHOD
Micrograph from SEM Intercritical annealing process
On the iron phase diagram
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
TRIP Steel

7. 30-01-2015 7
CHARACTERISTICS OF TRIP STEELS
CHEMICAL COMPOSITION
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
TRIP Steel

8. 30-01-2015 8
CHARACTERISTICS OF TRIP STEELS
MECHANICAL PROPERTIES
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
TRIP Steel

9. 30-01-2015 9
CHARACTERISTICS OF TRIP STEELS
MECHANICAL PROPERTIES
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
TRIP Steel

10. 30-01-2015 10
CHARACTERISTICS OF TRIP STEELS
FATIGUE STRENGTH
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
TRIP Steel

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CHARACTERISTICS OF TRIP STEELS
IMPACT STRENGTH
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
TRIP Steel

12. 30-01-2015 12
CHARACTERISTICS OF TRIP STEELS
ELONGATION Vs UTS
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
TRIP Steel

13. 30-01-2015 13
CHARACTERISTICS OF TRIP STEELS
FORMABILITY
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
TRIP Steel

14. 30-01-2015 14
CHARACTERISTICS OF TRIP STEELS
RESISTANCE SPOT WELDING
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
TRIP Steel

15. 30-01-2015 15
ECONOMICS OF TRIP STEELS
•Usually, steel is used for its strength, formability and
low cost relative to other metals.
•Titanium, magnesium and aluminum offers significant weight
savings in automobile components.
•Lower abudance, high production cost and high machining cost.
•TRIP steels don not face any of these difficulties, because they are
low alloy steel.
•TRIP steels can be produced for the same price as other high
strength steel.
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
TRIP Steel

16. 30-01-2015 16
APPLICATION
•As a result of their high energy absorption capacity and
fatigue strength, TRIP steels are particularly well suited for
automotive structural and safety parts such as
Cross members,
Longitudinal beams,
B- pillar reinforcements,
Sills and bumper reinforcements.
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
TRIP Steel

17. 30-01-2015 17
REFERENCES
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
1. http://en.wikipedia.org/wiki/TRIP_steel
2. http://www.arcelormittal.com/automotive/saturnus/sheets/
B_EN.pdf
3. http://www.keytometals.com/page.aspx?ID=CheckArticle&sit
e=kts&LN=EN&NM=194
4. http://www.appropedia.org/Transformation_Induced_Plasticit
y_%22TRIP%22_Steel
5. http://coursenotes.mcmaster.ca/701.../701_Yankui_Bian_Jan_
16_08.pdf
TRIP Steel

18. Thank You
Mohammed Ajmal Sheriff.F
m.Tech-manufacturing engineering.
b.s.abdur rahman university.
30-01-2015 18
TRIP Steel