mip tmcp 2009 iran

8/8/2019 Mip Tmcp 2009 Iran

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voes t a lp ine Grobblec h Gm bHwww.voestalpine.com/grobblech

TMCP-steels for offshore applications

Our plates run on l ine through water


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voes t a lp ine Grobblec h Gm bH

General applications for TMCP-steels


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Offshore applications for TMCP-steels


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TMCP - (Thermo- Mechanical- Control- P rocess) steelsare fine-grain steels with

excellent weldabilityhigh strength combined with high toughnessbest formabilityhigh reliability in welded structures

TMCP -Steels are produced withvery pure steel (low S-, P-, tramp element level)

low contents of micro-alloyinghigh-quality processing during melting,casting, rolling and accelerated cooling

What are TMCP-steels?


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Production route

LD-converter Vacuum-degassing Continuous casting

Plate rolling Accelerated cooling Plate finishing


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Yield strength / carbon equivalent

CEV= C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15

N...Normalised rolledQT...Quenched and tempered

TM...Thermomechanically rolled

AC (+T)...Accelerated cooling

(+ tempered)

DQ (+T)...Direct quenched

(+ tempered)

A t t h e s am e y i el d s t r e ng t hleve l TMPC-s t ee ls provi det h e l ow e st c a rb onequi va le nt (CEV).


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TMCP Thermo Mechanical Control P rocess

T e m p e r a t u r e

Time

roughing

final deformation

airair

air

water

T > T RS

T < T RS

Normalised TMCP+ACC TMCP

TMCP+ACCl e a ds t o

f i n e st g r a in


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TMCP-

processes

MAE

+T

TM1 TM2 TMAC TMDQ

TNrAr3

Ar1

Ms

(*) (*)

Rolling Accelerated Cooling T ... Tempering

T e m p e r a t u r e

MAE...Microalloying elements

TNr ... Recrystallisation-stop-temperature

Ms ... Martensite-start-temperature

TM ... Air cooling

TMAC ... Accelerated cooling

TMDQ+T ... Quenching+tempering


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Effects of finer grain

TMAC

TM 2

TM 1

NFiner grain results in- Higher strength

- Higher toughnessCE IIW = 0.40

CE IIW = 0.35

CE IIW = 0.35

CE IIW = 0.35

- C , + M n , + M L

- C , + N i , + C u

N...Normalising rolledTM...Thermomechanically rolledAC...Accelerated cooling


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Lower Carbon Equivalent (CE) with TMCP-steels

S 460 ML : TMCPS 460 NL: norm al i sed

Grade C Si Mn P S AL Cr+Ni+Mo+Cu V Nb Ti CE IIWS460 ML 0,036 0,30 1,35 0,0056 0,0005


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TMCP versus NORMALISED Plates

A dvant age Reason

Better weldability Low carbon equivalent Fine microstructure

Better formability Fine microstructure

Higher toughness Fine microstructureShorter processing time No heat treatment

Clean surface Thin, homogenous scale

Why t o pr e fe r TMCP ?


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Better weldability with TMCP-steels

Lower carbon equivalentNo preheating or lower preheatingWelding with lower repair rateNo stress release heating after welding

Lower hardness increase in the HAZ ( Heat Affected Zone)Higher toughness in the HAZ

Lower risk of cold cracks in the HAZ

Co s t r e du c t i o n

Re l i ab le w e lded jo in t


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Heat treatment and forming of TMCP-steels

Flame levelling short-termis permitted up to 700 C

No heat treatment, no hot formingIt deteriorates the microstructure ofTMCP and thereby the performance

Warm forming is possibleup to 580 C


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TMCP-s t ee l s m odern s t ee l s fo r t he fu t ure !


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mip tmcp 2009 iran

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