VA-High-strength heavy platesHochfesterStahl_E_02062008

We follow the dynamics of the markets and offer solutions to our customers to increase their performance. This is the mission of voestalpine Grobblech. For innovative solutions we use our technological experience from the energy branch.Moreover we are “on top” in processing technology – especially in thermomechanical rolling. The result: our high-strength and wear-resistant steels.

…Energy and mobility change our world.

We have the materials.“

2Our expertise meets customer requirements in demanding branches.

High-strength steels are a strategic niche of voestalpine Grobblech with strong growth. We promote thermomechanically rolled high-strength steels and have developed a highly advanced online accelerated cooling process. This aims in high-strength heavy plates with excellent weldability, very high toughness and good surface.

Typical fields of application

Mobile cranes

Concrete pump trucks

Vehicles and trailers

Mining equipments

High-pressure pipes

Offshore platforms

The market

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Things get bigger – often double size. If you double the size of a construction (double length, width and height), then weight increases by factor 8 while the cross section is raised by factor 4. Therefore the stress in the component material is doubled.

High-strength steels

Why high-strength steels?

High-strength steels can bear

higher stresses than normal-

strength steels. For a given load

respectively a fixed stress in the

component high-strength steels

lead to smaller cross-sections and

therefore to reduced weight which

results in decreasing costs.

Weight: (2 l x 2 w x 2 h) x ?=x 8

Cross-section: (2 l x 2 w) =x 4

Stress:weight / cross-section =

x 2 l length

w width

h height

?specific weight

... double size means double stress ...

4

524 %42 %

Reduced

thickness Reduced weld volume

S355S460Cost benefits

Reduced steel weight leads to

Reduced purchasing volume

Reduced costs for transport, assembly and foundations

Reduced costs during further processing, especially in welding

? Less filler material

? Less welding time

? Less expense for checking the welds

What about high strength?

Reduced thickness leads to superproportionally reduced weld volume.NR normalising rolled

TMCP thermomechanical control process

Q+T quenched and tempered

T tempered

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TMCP

TMCP- (Thermomechanical Control Process) steels are fine grain steels with

High strength combined with high toughness Excellent weldability Best formability

High reliability in welded structures

– High toughness in the heat-affected zone (HAZ)– High resistance against cold cracks

TMCP-steels from voestalpine Grobblech are produced with

Very pure steel (low S-, P-, tramp element level)Low carbon content and low carbon equivalent (CE)Microalloying

High-quality processing during melting, casting,rolling and accelerated cooling

Different rolling and cooling processes

No heat treatment

Normalising deteriorates the microstructure of TMCP-steels

and thereby their properties.

Hot forming and stress relief annealing

TMCP-steels are generally intended to cold forming. Hot forming

and stress relief annealing is possible up to 580 °C. Mechanical

properties may change due to heat input.

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Applications of TMCP-steels

voestalpine Grobblech has been among the pioneers in the field of the development of TMCP-steels. We have invested in the most mo-dern accelerated cooling line in Europe and operate a highly advan-ced cooling process. Some 500,000 tons of TMCP-steels we produce year by year with increasing tendency. TMCP is our daily business.

Thermomechanically rolled steels are widely

used in different applications:

Oil and gas pipelines onshore and in deepwater

Offshore platforms

Bridge building and mining equipments

Buildings and structural steel work

Mobile cranes and vehicles

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Plate rolling Plate finishing Accelerated cooling LD-converter

Continuous casting Vacuum-degassing 9Production route of TMCP-steels

Our plates run online through water – no heat treatment

10TMCP-steels provide best weldability

Low risk of cold cracks

Due to the low-alloyed chemical composition and the low carbon equivalent (CE) TMCP-steels are perfectly weldable. Especially the low carbon content results in excellent resistance against cold cracks after welding.

Carbon equivalent CE

0.1

0.20.30.4

C a r b o n c o n t e n t [%]0.30.40.50.60.70.80.9

*High strength welding consumables may require additional care

CE = C + Mn/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15 according to IIW

Fabrication benefits of TMPC-steels

Remarkable reduction or elimination of preheating

–Great savings in fabrication costs

–Improved working environment for operators

Reliable welded joint

–Almost no additional repair welding

even without preheating High heat input welding –Major reduction of welding pass –

Far lower welding costs

–Much shorter fabrication time

Easier surface cleaning due to thin, homogeneous scale

11For information about welding of “voestalpine high-strength heavy plates” please choose a Brand and follow the link sequence described:

ffcd4dcad15abe23482f4d5a > Industry Focus

> voestalpine high-strength heavy plates

ffcd4dcad15abe23482f4d5a

> Products

> Product Search

> voestalpine high-strength heavy plates T-PUT –welding solutions at its best…

B?hler Welding –

Welding consumables for

high demanding industries

Brands

We offer special high-strength heavy plates as voestalpine brands according to our technical terms of delivery.TMCP

Thermomechanically rolled fine-grain steels Steel grades:alform 700 M alform 960 M Online production by thermomechanical

rolling and accelerated cooling directly after

hot rolling – no bottle-neck.

Quenched & tempered

Offline production by conventional quenching

and tempering: annealing with subsequent

water-quenching and following tempering. The

double heat treatment may lead to a bottle-neck.

Quenched and tempered fine-grain steels Steel grades:aldur 700 Q aldur 700 QL aldur 700 QL112

13Benefits

High-strength alform ?-steels are thermomechanically rolled and

accelerated cooled.

These special grades of voestalpine provide:

Excellent cold formability

–Smaller edging radius compared to standard steels of same

strength

Best weldability

–Due to low carbon content and carbon equivalent

–Reduced preheating or even no preheating necessary

Clean surface due to thin, homogeneous secondary scale

Wide range of steel grades and dimensions

–Steel grades: alform 700 M up to alform 1100 M

–Thickness: 2.5 - 60 mm

–Width: 900 - 2,500 mm

Products

voestalpine produces and delivers hot-rolled high-strength

alform ?-steels in form of:

Hot-rolled wide strips

Sheets of hot-rolled wide strips

Heavy plates

The different production routes result in specific advantages of the

different products. The exact properties and guaranteed values of

these products you will find in the technical terms of delivery at

ffcd4dcad15abe23482f4d5a/stahl and ffcd4dcad15abe23482f4d5a/grobblech.

Hot strip mill Heavy plate mill

14alform 700 M and alform 960 M – heavy plates

Thermomechanically rolled high-strength fine-grain steels with a

minimum yield strength of 700 MPa and 960 MPa.

voestalpine special grades alform 700 M and

alform 960 M are mainly used in branches with a

high extension of manufacturing, when weight

savings are the main goals to reach. This is typi-

cal in the field of mobile cranes, concrete pump

trucks and vehicles.

15Production process

Dimensions

You will find more information in our technical terms of delivery. Subject to change pursuant to further development.The current version is available at ffcd4dcad15abe23482f4d5a/grobblech

alform ?-steels are produced by thermomechanical rolling with accelerated cooling directly after the rolling process. Conventional quenching and tempering in heating furnace and quenching device is no longer necessary. This type of steel provides a fine-grained, homogeneous structure with high tensile strength and excellent toughness.Benefits

alform ?-steels show benefits in comparison with

conventional quenched and tempered steels as

following:

Best weldability because of low C-equivalent,

low C-content, easy edge preparation, reduced

or abolished preheating, high resistance against

cold cracks because of high toughness in the

heat-affected zone (HAZ).

Best bending properties because of the very

fine grained structure, smallest bending radius

and insensibility against cracks during bending.

Best surface because of a homogeneous, thin

secondary scale which is easily to remove. No

scale scarred from hardening process. Steel grade Min.Max.

Thickness alform 700 M 8 mm 60 mm

alform 960 M 10 mm 15 mm

Width 2,500 mm Length 12,750 mm Weight per order item 20 mt

Weight per plate 11.7 mt

1)CEV = C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15 according to IIW 2)

CET = C + (Mn+Mo)/10 + (Cr+Cu)/20 + Ni/40 according to SEW 088

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Chemical composition

Carbon equivalent

The lean chemical composition is designed for best weldability. Therefore we provide very low carbon- and carbon equivalent values.

Heat analysis Guaranteed values

mass %

C

Si Mn P S Al ges.Cr Mo Ni V Nb Ti

B Steel grades max.max.max.max.max.min.max.max.max.max.max.max.max.alform 700 M 0.120.60 2.100.0200.0080.020 1.500.50 2.000.120.060.050.0050alform 960 M

0.12

0.60

1.70

0.020

0.008

0.020

1.50

0.70

2.00

0.12

0.06

0.05

0.0050

As-delivered condition

Plates of alform 700 M are delivered in a thermomechanically rolled condition with accelerated cooling.

Plates of alform 960 M are delivered in a thermomechanically rolled condition with accelerated cooling and tempering. Mechanical properties

1)Tensile test in accordance with EN 10002 on transverse samples.

2)Notch impact bending test in accordance with EN 10045 on Charpy-V longitudinal samples at –40 °C.

The mean value from 3 inpidual sampels must fullfil the specified requirements. No inpidual value below 70% of the guaranteed

mean value. For thicknesses < 10 mm, samples similar to Charpy-V with dimensions of 10 x 7.5 mm are tested. The guaranteed value

is reduced in proportion to the sample cross-section.

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18Safety at overload

alform 700 M provide a low ratio of yield strength to tensile strength. This aims in additional safety in case of overload.

Excellent toughness

alform 700 M provide excellent toughness down to very low temperatures. Skillfully welded this aims also in high toughness in the heat-affected zone (HAZ) for a reliable welded joint.

Item 1

With beginning overload alform 700 M strengthens

more, but with less elongation than S690QL.

Item 2

Increasing overload reaches the tensile strength for

S690QL while alform 700 M is still strengthening.

Item 3

While alform 700 M is still strengthening, the tensile

strength of S690QL is already passed.

Elongation

Stress strain curves (detail)

S t r e s s [M P a ]

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Optimal Welding

Reduced preheating

The very low carbon- and carbon equivalent values reduce the preheating temperature significantly or even make pre-heating not necessary. This saves fabrication costs and improves the working environment of the operator.

Lower hardening

Due to the lean chemical composition the hardening in the heat-affected zone (HAZ) during welding ist remarkable lower compared with conventional quenched and tempered steels. This results in lower risk of cold cracks and a reliable welded joint.

Arc energy [kJ/mm ]

M a x . h a r d n e s s i n H A Z [H V 10]

Hardening in heat-affected zone [HAZ]

MAW – welding, 12 mm thickness

20Tests for alform 700 M: plate thickness of 10 mm, bending direction parallel to rolling direction

Q+T steel plates: Quenching & tempering leads

to thick scale from the furnace. During levelling

there is a risk of getting marks of impressed

scale. alform ?-plates: TMCP provides thin homogene-ous scale from hot rolling. The risk of scale im-pressions is reduced.

Best bending properties

The fine-grained structure of alform ?-steels provides very good cold formability. We recommend a minimum die-radius of: 3 x plate thickness for alform 700 M (EN 10025-6: 4 x)4 x plate thickness for alform 960 M (EN 10025-6: 5 x)

Less scale on surface

Due to the TMCP online-production with accelerated cooling alform ?-plates provide a thin homogeneous scale. This results in less scale during processing in the costumer’s workshop.

measured inner radius / thickness

(c r

a c k

l

e n g t h / b e n d i n g l e n g t h ) x 100 [%]100

9080706050403020100

Bending performance

10 mm 10 mm

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