presentation on IFHS STEEL

7/23/2019 presentation on IFHS STEEL

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KIRANKUMAR

MTECH(materials eng.)


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Deformation

Recovery

Re-crystallization

Recovery kinetics

Re-crystallization kinetics

Discussion

Conclusion


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Plastic deformation

Change in dimensionof metal under load

Change in grainsize, strength,

number ofdislocation

Increase in hardness,strength, decreases

ductility

Deformation

Elasticdeformation

Teture


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!efore cold "ork #fter cold "ork


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Dislocations allow deformation at much lowerstress

than in a perfect crystal


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O% cold work micro structure of IF-HS

#fter $%& cold "ork 'I(-)*+


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Recovery

Restoration of hysicalroerties cold "orkedmetal "ithout changein microstructure

Change inhysical,

mechanicalroerties

Increase inelectrical

thermalconductivity

#nnealing

Re-crystallization

.rain.ro"th


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Highlyrecovered

Some recovery

Recovery


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Recovery kinetics rate of recovery inversely proportional to

annealing time d /dt = -/t

=!- ln t " w#ere "!are constant -y =$%&'()/*

w#ere $ depends on material

is constant

& is elastic s#ear modulus

' is 'urger+s vector is applied stress

yis yield stress of crystalli,ed material


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Re-

crystallizationRelacement of

cold "orkedstructure by ne"set of strain-free

grains

*tored energy isdriving force forrecovery re-crystallization

increase in area of grainboundary due to increase

in grain size

/inimum

amount ofdeformationis needed forrecrystallizati

on

Decrease in hardness strength , increasein ductility , density

of dislocation

decrease

heterogeneou

s


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Factors inuencerecrystallization

#mount ofdeformation

Time

TemeratureInitial grain size

Comosition

#mount ofrecovery


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E0ects of cold "ork are reversed1


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conclusionnergy stored is driving force for recovery " re-

crystalli,ation.ecovery 'y release of stored energy

ovement of dislocation into su'-grain

inimum amount of deformation need for re-crystalli,ation

/#ermal cycling t#roug# #ig# temperature leads recovery

structure


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Publication0Effect of mode of rolling on re-crystallizationkinetics and microstructure evolution in IFHS steel sheet, ISIJinternational , vol!"#$%&"',(o$,))"!*-"*+

E)erience0 One year work e1perience on 2F/ t#eory

Publication Effect of .oic gas #/l$' on Electronic and.rans)ort )ro)erties of 0igzag 1oron (itride (ano 2ibbon First

)rinci)les study #under review'


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THANKS A LOT

ANY QUESTION

PLEASE

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presentation on IFHS STEEL