HHO-05.085

Hot-rolled, Boron-Alloyed SteelsThe strong alternative with economic focus

Hoesch Hohenlimburg

tk

A company ofThyssenKrupp

Steel

lowing hardening, temperingtreatment possibly redundant

• overall size range up to max 685 mm wide and max 16 mm thick

In addition to standardisedboron-alloyed grades, we havedeveloped market-orientedanalysis variants as trademarks, which meet specificrequirements. Just talk to ourapplication consultants!

It is precisely the automotivesector which calculates inlarge numbers of items. Whatcounts are components withuncompromising economicefficiency – using Hohenlim-burg production and develop-ment capacities.

It is only developers who havethe choice and, depending on the material requirements,who can decide with a clearconscience for the more favour-able solution. With HoeschHohenlimburg narrow strip allrequirements can be met: extremely rational basic materialwith boron-alloyed steels – asthe current alternative to con-ventional heat-treatable steels.

More and more Hoesch special-ists are involved in the auto-

Boron-alloyed case hardening and heat-treatable steels: Robust qualities for specific requirements

motive field as well as in theclassical agricultural fields, from economical and technicalplanning up to and includingfinished components. Alwayswith the backing of productionon the most modern plant – within the meaning of optimumquality.

Boron-alloyed steels fromHohenlimburg narrow stripshow their strengths traditionallywhere it all depends on stablesecurity with economic condi-tions:

• considerably increased hardening capability

• achieving high strengths withhardening and tempering

• better processing through lowcarbon content

• already very good ductility fol-

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Pages 6-7Chassis and drivesystemsRobust long-life mate-rials hold their own inhard cost competition

Pages 4-5Interior /seats/doorsOutstanding mechanicalquality values with thestrongest hardeningcapability effect

Pages 8-9Agricultural machinery/cutting toolsReliable materialdurability with fatiguestress and maximumloading

Page 10ServiceEconomic furtherprocessing of thematerial and to thissupport from A to Z

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Selector fork Grade: HLB 27

Only one of many highlights

Reliable and nevertheless cost-effective in manufacture – these are the central requirements oncomponents in the area of theinterior and restraint systemassemblies. Whether it is continu-ous stress or maximum loading inemergencies – the material musthold!

Absolutely decisive here are exactanalysis and precise production,which is monitored at every step.

Laboratory tests have determinedthe achievable hardness for theindividual grades in the hardenedand, at 200 respectively 400 °C,tempered condition (see diagramon Page 5). In addition, detailedtempering diagrams for waterhardening and oil hardening at650 °C are created and regressionanalytically prepared.

Assembly: Interior/seats/doors

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Window winder linkageGrade: HLB 8

Angle bracket Grade: HLB 27

Door holding arm for passenger vehicleGrade: HLB 8

When the chips are down: safety has right of way!

Detent latch Grade: HLB 8

Toothed segment Grade: HLB 8

The ductile behaviour was examinedwith the aid of notched bar testsand notched impact strength testsin accordance with DIN 11 100. The important position of thesupplier for safety systems allowsno compromises. That is the standard!

HHO-05.085

Comfort and convenience

are today decisive parameters.

Simply – the material must fit!

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Passenger vehicle seat backrest adjustor Grade: HLB 27

Seat Belt tensionerGrade: HLB 27

HLB 22

60

55

50

45

40HLB 27 HLB 30 HLB 37 HLB 42

After quenching

HLB 22

60

55

50

45

40HLB 27 HLB 30 HLB 37 HLB 42

Tempered at 200 °C

HLB 22

60

55

50

45

40HLB 27 HLB 30 HLB 37 HLB 42

Tempered at 400 °C

Water quenching

Oil quenching

Assembly: Chassis and drive systems

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Selector fork component:Grade: HLB 27

A recommendation on the quality: durability simply drives better

HHO-05.085

Precision in performance is our objective.

Here only quality gets the green light!

Boron is the alloying elementwith the strongest durabilityincreasing effect. It delays theconversion into softer types of microstructure and, withhardening, a martensitic micro-structure develops across thestrip cross-section. Throughdefined, small additions ofboron (ca. 30 ppm) in combi-nation with lower carbon con-tent the same hardness isachieved as with conventionaltempering steels.

Axles and gearboxes havesimply to function permanently– any defect can have as aresult the most dangerousdriving situations.

Therefore durability andstrength values of the materialsused are decisive. The outstan-ding mechanical quality valuesof the Hoesch trade marksspeak for themselves.

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Rear axle tube Grade: HLB 27

These lower carbon contentsimprove the processing proper-ties.

Expensive alloying elementssuch as Cr, Ni or Mo can bedispensed with in part orcompletely.

Depending on the range ofapplication a tempering treat-ment can be dispensed withfollowing hardening, as a highdurability already exists in thequenched condition.

Boron-alloyed steels fromHoesch Hohenlimburg offer an ideal platform when whatmatters is the combination of design modifications withfavourable forming properties.

Whether sweeping or painstaking: diverse design success brings in the harvest

Metal on stone – that grates! Inhard agricultural use such loadingtests are a daily event.

No wonder that developers ofagricultural machinery employ the most robust and most durablematerials, which of course havealso to hold their ground in thehard cost competition: boron-alloyed steels from HoeschHohenlimburg.

Sound base for these products isthe production train for narrowstrip. Not only several mill standsbut rather an interlinked plantmade up of furnaces, reversingmill, thermal tunnel, finishingtrain, cooling line and coiling plantprovides, highly automated, fordefined results. In order that thequalitative lead remains maintai-ned permanently, the latest state-

Assembly: Agricultural machinery/cutting tools

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Ploughshare Grade: HLB 40

Chaff cutter bladeGrade: HLB 20/22

Driving shaftagricultural machine

Grade: HLB 22

HHO-05.085

For many mobile fields of employmentboron-alloyed steels are the firstpreference. All design requirements with regard to stability and reliability are certainly capable of realisation.

In daily practice

down times are a catastrophe.

Permanent reliability shows its strength here!

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Very nearly unlimited possibilities

of-the-art is realised with significantinvestment volumes – most recentlywith the new coiling plant and thesecond walking beam furnace.

Permanent quality control is a factorwhich, with HHO, is not only certifiedby the most up-to-date qualitymanagement system. Innovations for on-line testing and monitoring are being continuously developedand implemented – such as the newrolling information service or coilingshape measurement. Entirely withinthe sense of optimum customersatisfaction.

Spring collet Grade: HLB 37

It all depends on solid consistency.

Diamond-steel bladeGrade: HLB 27

Reaper blade Grade: HLB 37

On the complete line:Support for optimum results

Economical fine blanking

Boron-alloyed steels, depending on the qualityand application, can have economic fine blankingeven without previous annealing treatment.Ask us for details!

Versatile cold-forming

Already in the hot-rolled state, boron steels show good forming properties. Dependent onthe annealing treatment and structural conditioneven the most difficult cold-forming is thuspossible.

Welding without problem

Due to its low carbon content compared withnormal heat treatable steels, boron steels aresignificantly better suited for welding.

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Boron-alloyed steels – Ideal for further processing

In full attendance from the start – or detailed questions first at a later date?

Decide yourself at which point in time and to whatextent you wish to make use of our comprehensivecustomer service.

We support you completely individually and practically:

• advice on the selection of materials

• further development of materials according to your requirements

• support with optimisation of your fabrication

• laboratory investigation.

Simply talk to us – our technical customer service isthere for you!

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Hoesch Hohenlimburg GmbH

D-58119 HagenTel.: +49 (0) 23 34/91-23 91 or 91-0Fax: +49 (0) 23 34/91-33 69

Technical Customer Service: Tel.: +49 (0) 23 34/91-3253

-2271-2295

Fax: +49 (0) 23 34/91-33 58E-Mail: info.hoesch-hohenlimburg@thyssenkrupp.comInternet: www.hoesch-hohenlimburg.de

Oeger Strasse 120