Development of new rail material · 2018. 7. 4. · EN13674-1:2011 Available and in all rail profiles Full weldability Used in any kind of traffic type fine-lamellar HE Perlite R400HT

voestalpine Schienen GmbH voestalpine Schienen GmbH www.voestalpine.com/schienen

Development of new rail material

Dr. Sören Röhrig voestalpine Schienen InnoRail – Workshop Hilversum, 14th June 2018

P1824

voestalpine Schienen GmbH | |

The rail

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The characteristics of a rail

Rail profile

Geometry and dimensions

Rail as load carrier

Rail/Wheel contact condition

Widerstandsfähigkeit des Werkstoffs

(Schiene als Fahrbahn)

InnoRail


The rail

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Light microsope The characteristics of a rail

Rail profile


Rail as load carrier Rail/Wheel contact condition

Rail steel grade

Microstructure and mechanical figures

„Strength“ and resistivity of the materialfüge und mechanische Kennwerte

Widerstandsfähigkeit des Werkstoffs (Schiene als Fahrbahn)

InnoRail


The rail

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The characteristics of a rail

Rail profile


Rail as load carrier Rail/Wheel contact condition

Rail steel grade

Microstructure and mechanical figures

„Strength“ and resistivity of the materialfüge und mechanische Kennwerte

Widerstandsfähigkeit des Werkstoffs (Schiene als Fahrbahn)

SEM image

InnoRail


Load between Rail and Wheel

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Load in the Rail/Wheel system

Normal- und tangential forces

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Q Y

InnoRail



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Slip and slip forces

» Longitudinal Slip due to acceleration and break

» Transversal slip due to flange contact

» Spinning slip due to geometrie

InnoRail



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InnoRail



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R260

Pmax = 1385 MPa

Rm = 900 MPa






Load in the Rail/Wheel system is

beyond the material strength

InnoRail



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Load in the Rail/Wheel system is

beyond the material strength

Cyclic compression and shear

in the contact area

InnoRail


How does the material react?

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The reaction of rail material due to load

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High shear deformation of the

rail material at and below the

surface

All the mechanical figures of

the bulk material break down


Example R260

Cold deformation 200%

Elongation -90%

Fracture toughness -85%

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surface




InnoRail


Microstructure of the bulk material

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surface




InnoRail


Highly deformed microstructure

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surface


the bulk material break down.


InnoRail

voestalpine Schienen GmbH | | 14.06.2018 16



surface.



Highly deformed area is origin

of rail damage


InnoRail


Common rail material and how to improve.

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lammellar

Perlite R260

Improving the resistance of rail material

Lamellar microstructure of two

phases

Basically suited to defeat high

contact load, wear and rolling

contact fatigue

As-wolled R260 Perlite as starting

point for further development

(as an essential reaction due to the

steadily increasing load)

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lammellar

Perlite R260

fine-lamellar

Perlite R350HT


Fine microstructure

Fining due to heat

treatment

Higher density of

lammelars enhancing

the resitance against

deformation

Big scale production

since early 1990

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fine-lamellar HE

Perlite R400HT

Fine and strengthend microstructure


lamellarer

Perlite R260

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Fining due to heat

treatment in combination

with strengthening due to

HE-concept.

Improved phase equilibrum

for highest resistance.

Big scale production

since 1999

InnoRail


Non-alloyed rail steel

grade according to

EN13674-1:2011

Available and in all

rail profiles

Full weldability

Used in any kind of

traffic type

fine-lamellar HE

Perlite R400HT

Fine and strengthend microstructure

Increasing the resistance of rail material

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lamellar

Perlite R260

fine-lamellar

Perlite R350HT

fine-lamellar HE

Perlite R400HT


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Fine microstructure Fine and strengthend microstructure



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Cold-hardening of the sub-

surface material is a indicator

of the disruption of the

microstructure.

Rail steel grade R400HT

= More stable microstructure

= Lower degree of deformation

= Less depth of deformation

R400HT

R350HT

R260

InnoRail


Increasing of hardness vs.

Improving of resistance

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Increasing of hardness

» Some developments had/have

the target just to increase the

hardness

1. alloying with Chromium as indicated by nomenclature

» R260 R320Cr

» R350 R370CrHT

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0,15% to 0,30%

450 HBW 400 HBW





hardness

2. alloying with other elements

making extra hard test rails

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hardness

2. alloying with other elements

making extra hard test rails

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hardness

3. „Vanadium“ steel grades » increased hardness

» no influence on weldability

» no performance benefit

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hardness

1. Adding Chromium

2. Extra hard test rails

3. Vanadum

InnoRail


Performance in track

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Performance in track: Wear

R350HT R400HT

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Schienenprofilmessungen im Gleis, zeitliche Entwicklung 2007 - 2010

High strength rail grade R400HT

provides:

Low side wear

Expanded lifetime

Low guiding forces in curves

due to a high profile conservation

and thus a preferable contact

geometry

InnoRail

voestalpine Schienen GmbH | | 14.06.2018 InnoRail 32

Bogeninnenschiene

(Low Rail)

Bogenaußenschiene

(High Rail)

Performance in track: Wear


Performance in track: Corrugation

gemessen nach jeweils 1 Jahr in Betrieb

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provides:

Reduced corrugation growth

Less maintenance needed

Less noise and vibration

InnoRail


Performance in track: Rolling Contact Fatigue (RCF)

2,2 mm

1,2 mm

0,44 mm

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provides:

Lowest RCF damage depth

Less maintenance needed

InnoRail


Bring-home message

InnoRail 14.06.2018 35


Innovative steel design

Improved and strenghened rail

material (100% perlitic) – R400HT

Less deformation and cold-hardening

in the surface area

Showing less deterioration

Best Performance in track

Just increasing the hardness without a

metallurgical concept is not a valuable

concept

14.06.2018 InnoRail 36

voestalpine Schienen GmbH voestalpine Schienen GmbH www.voestalpine.com/schienen

THANK YOU! Sören Röhrig Product Management +43 664 88322677 [email protected]

Documents

Development of new rail material · 2018. 7. 4. · EN13674-1:2011 Available and in all rail profiles Full weldability Used in any kind of traffic type fine-lamellar HE Perlite R400HT