Att välja material till bärande konstruktioner - SBI · Att välja material till bärande konstruktioner Hasse Groth & Thérèse Sterneland Avesta Research Center. Outokumpu. Älvsjö

Att välja material till bärande konstruktionerHasse Groth & Thérèse SternelandAvesta Research CenterOutokumpu

Älvsjö 2017-10-25

10/30/2017 2

Innehåll

1. Vad är rostfritt stål och olika typer?

2. Duplexa rostfria stål

3. Att välja material

4. Erfarenheter

10/30/2017 3

Vad är rostfritt stål?

Fe + >10.5% Cr“1 mm“

Vykort• Järn med tillsats av minst 10.5% krom

• Naturligt bildad passivfilm

• 20-30 Å = 0.000 002 - 0.000 003 mm

• Självläkande

passivfilm

10/30/2017 4

“Det finns rostfritt……

…. och sen så finns det syrafast”

10/30/2017 5

• Kombinationen av legeringselement ger en mikrostruktur som ger vissa typiska egenskaper. Ståltillverkare gillar denna indelning! (Tillverkning Världen/Sverige)

Olika typer av rostfria stål

Ferritiska stål Krom.Magnetiskt. Vanligt förekommande. (19/1%)

Martensitiska stål Krom + ganska mycket kol.Ej i Eurocode Hög hållfasthet, härdbara. Knivstål.

Duplexa stål Mycket Krom – lite Ni, Mo, N. 50% ferrit-50% austenit Hög hållfasthet. Växer snabbast. (1/29%)

Austenitiska stål Krom + Nickel (Mo, N). Formbarhet, svetsbarhet. Vanligast. (80/70%)

10/30/2017 6

Olika typer av rostfria stål-olika egenskaper

Ferritiska stålLämpliga i mildare miljöer

Martensitiska stålLämpliga i milda miljöer därhårdhet krävs

Austenitiska stålFrån milda till aggressiva miljöer

Duplexa stålFrån milda till aggressiva miljöer, hög hållfasthet

10/30/2017 7

Innehåll




4. Erfarenheter

8

What is Duplex Stainless Steel?• Duplex stainless steel has a ferritic-austenitic

microstructure

• The phase balance is approximately 50% ferrite and 50% austenite

• Duplex stainless steel combines most of the beneficial properties of ferritic and austenitic steels

• The duplex microstructure contributes to high strength and high resistance to stress corrosion cracking

9

Duplex- a long history at Outokumpu

Seawater

Dec 23, 1930

453S (~ASTM 329)Brobeck cooler in grade 453 S

10

History

Second generation Duplex

• Process development (AOD)made it possible to reducethe carbon content and toalloy with nitrogen.

• The nitrogen improved the formation of austenite after welding

• 2205 was invented in the 1970’s

11

History

Third generation Duplex

• Super duplex

Grades with Cr content 25% or more

High levels of Cr, Mo, N and sometimes W give high resistance to localized corrosion

• Lean duplex

Grades with low Ni content often replaced with Mo and N

Forta range

12

13

Product performance comparison

Yield strength vs. corrosion resistance

PRE = % Cr + 3.3 x % Mo + 16 x % N. Yield strength (Rp0.2) uses EN 10088-2 minimum values for cold rolled strip

Forta range Duplex

Positioning of Duplex gradesAn excellent combination of high strength and corrosion resistance

600

550

500

450

400

350

300

250

200

150

Dup

lex

Aust

entic

Core 304L/4307

Supra 316L/4404

Supra 316L/4436

Ultra 317LUltra 4439

Ultra 904L Ultra 254 SMO

Ultra 4565

Forta LDX 2101

Forta DX 2304

Forta DX 2205

Forta SDX 2507Forta LDX 2404

Corrosion Resistance, CPT typical

Stre

ngth

, Rp0

.2 [M

Pa]

Hot coil

Ultra 654 SMO

14

Forta EDX 2304

Duplex products• HRP(P), Quarto Plate: t = 2-100* mm

• CPP(H), coil and plate: t = 4-10* mm

• CR (C), coil, strip & sheet: t = 0.1-6* mm

• Billet, wire rod, bar and rebar

• Welded tube and pipe

• Fittings

• Structural profiles - Duprof™: ≤ 6 m as standard, max 13 m

*Max/min. thickness – grade and width dependent.

15

Duplex = Austenitic + Ferritic structure

16

Ferrite Austenite

Duplex

High Mechanical StrengthSolid Solution hardening

17

Atoms of another size than the pure metal is causing a disorder in the material which leads to hardening.

Nitrogen is an example of a small atom that solutes between the iron atoms in stainless steels.

18

General characteristics of Forta range Duplex products

• High mechanical strength (Rp min > 400 MPa)

• High resistance to localized corrosion (PRE 26 to 43) and stress corrosion cracking

• High wear resistance• Low thermal expansion• High energy absorption• Good fabricability

Cost effective and sustainable solutions

Courtesy of Outotec.

19

• Storage tanks

• Pressure vessels

• Bridge components

• Flexible pipes (Oil & Gas)

• Blast walls (Offshore)

• Thickeners (Mineral processing)

• Water gates

Applications: Forta range duplex

Courtesy of IKM dsc Engineering

10/30/2017 20

Innehåll




4. Erfarenheter

10/30/2017 21

Korrosionsmotstånd, några vanliga stålOutokumpu EN Struktur Cr Ni Mo N PRE*

Moda 4016 1.4016 ferrit 16.2 16

Core 4509 1.4509 ferrit 18.0 18

Core 4307 1.4307 austenit 18.1 8.1 18

Core 4404 1.4404 austenit 17.2 10.1 2.1 24

Ultra 254 SMO 1.4547 austenit 20.0 18.0 6.1 0.20 43

Forta LDX 2101 1.4162 duplex 21.5 1.5 0.3 0.22 26

Forta DX 2205 1.4462 duplex 22.0 5.7 3.1 0.17 35

Forta SDX 2507 1.4410 duplex 25.0 7.0 4.0 0.27 43

*PRE, Pitting Resistance Equivalent,

PRE = %Cr + 3.3 × %Mo + 16 × %N

PRE är ett grovt verktyg för att rangordna olika rostfria ståls motstånd mot punktfrätning

10/30/2017 22

PunktfrätningsegenskaperKritisk punktfrätningstemperatur, ASTM G150

100

90

80

70

60

50

40

30

20

10

0

CPT,

°C

1.40

16

1.45

21

1.44

32

1.44

04

Ultra

904

L (1

.453

9)

Ultra

254

SM

O (1

.454

7)

Fort

aLD

X 21

01 (1

.416

2)

Fort

aD

X 23

04 (1

.436

2)

Fort

aD

X220

5 (1

.446

2)

Fort

aSD

X 25

07 (1

.441

0)

1.43

07

10/30/2017 23

“Det finns “rostfritt”……

…. och sen så finns det “syrafast”

10/30/2017 24

Urgammal tumregel:

“Rostfritt” inomhus

“Syrafast” utomhus

10/30/2017 25

Korrosivitetsklasser (ISO 9223) och erforderliga rostfria stål

ISO Corrosivity Typical environments Grades

C1 Very low Dry or cold zone: Central Arctic/ Antarctica and certain deserts. 1.4016, 1.4307, 1.4162

C2 Low Temperate zone: rural areas and small towns. Dry or cold zone: deserts and subarctic areas.

1.4016, 1.4307, 1.4162

C3 Medium Temperate zone: urban areas and costal areas with low deposition of chlorides. Subtropical and tropical zone: areas with low pollution.

1.4301, 1.4404, 1.4162, 1.4362

C4 High Temperate zone: polluted urban areas, industrial areas, costal areas without spray and exposure to de-icing salts. Subtropical and tropical zone: areas with medium pollution.

1.4404, 1.4162, 1.4362, 1.4462, 1.4539, 1.4410, 1.4547

C5 Very high Temperate and subtropical zone: industrial areas, coastal areas and sheltered positions on coast line.

1.4462, 1.4539, 1.4410, 1.4547, 1.4565, 1.4652

CX Extreme Subtropical and tropical zone: extreme industrial areas, coastal and offshore areas.

1.4410, 1.4547, 1.4565, 1.4652

10/30/2017 26

Eurocode 3: EN 1993-1-4:2006

10/30/2017 27

Eurocode 3:EN 1993-1-4/A1:2015

Corrosion Resistance FactorCRF = F1 + F2 + F3

F1 = Risk of exposure to chlorides from salt water or deicing salts; F2 = Risk of exposure to sulfur dioxide; F3 = Cleaning regime or exposure to washing by rain.

10/30/2017 28

EN 1993-1-4/A1:2015

10/30/2017 29

10/30/2017 30

Effekten av ytfinhetForta LDX 2101®, 2 års exponering vid Bohus Malmön, Svenska västkusten

Ra 0.2 µm Ra 0.5 µm Ra 0.8 µm

Finare ytor – mindre risk för initiering av korrosion

Missfärgning på ytan - Estetiskt, påverkar ej hållfasthet

10/30/2017 31

Påverkan av atmosfären

Chrysler Building, New York, byggd 1930. Paneler i typ 1.4301

10/30/2017 32

Case: Gateway Arch, USA

• Stainless steel load bearing structure made in 1965.

• Arch design included load bearing, welded, stainless steel plate in grade 316 (1.4401).

• Inspection after 50 years – Dirty, but in good shape!

• At that time - Minimal structural research, no duplex

• It was found that structural research was needed!

10/30/2017 33

Hur mycket rostar 1.4404 på ett tak i Stockholm?

1) Hur lång tid tar det innan 1 gram försvinner på en 1 m2 yta takplåt 1.4404?

(Tips: Materialet är beständigt i denna miljö. Det regnar på plåten regelbundet.)

2) En takplåt är normalt 0.5 mm tjock och väger 4 kg/m2. Hur lång tid tar det innan 0.1 mm försvinner?

Källa: Korrosionsinstitutet/KIMAB

10/30/2017 34

Innehåll




4. Erfarenheter

Vanliga duplexstål i broar

• Forta DX 2205, 1.4462

• Forta DX 2304, 1.4362

• Forta LDX 2101, 1.4162

• Forta LDX 2404, 1.4662 – Nytt

Inspection of Duplex bridges• To collect field experience of stainless steel bridges.

• Observe and record the condition and performance of various stainlesssteel components at site.

• Document and inform the designers of future stainless steel structureby providing a reference point for past sucessful applications.

• To provide data for future design standard revisions, EN 1993-1-4, Annex A relating to material selection.

Acknowledgement Sukanya Hägg Mameng och Jan Björk

Sölvesborg, 2013Grade 1.4162

Flen Bridge, 2009Grade 1.4162

Sicklauddsbron, 2002Grade 1.4462

Nynäshamn, 2011Grade 1.4162

Celtic Gateway, 2006Grade 1.4362

Saint Fruitos, 2009Grade 1.4162

Zumaia, 2008Grade 1.4462

Anorga, 2011Grade 1.4162

Puerto Arrupe 2003Grade 1.4362

Cala Galdana, 2005Grade 1.4462

Millenium, 2000Grade 1.4462

Spain

UK

Inspekterade broar

CRC III

CRC III CRC IV

CRC III

CRC II, III

CRC II, III

CRC II, IIICRC II, III

CRC II, III

CRC II, III

CRC IV, V

CRC = Corrosion Resistance Class (EN 1993-1-4 Annex A )

Klassningar

• Risk of exposure to chlorides from sea salt water• M=Distance from the sea

CRC II, III

Low *(M > 10 km)

Medium *(1 km < M ≤10 km)

High*(0,25 km < M ≤1 km)

Very high*(M ≤0,25 km)

CRC III CRC IV/V

Orrhammarvägen Bridge Duplex grade 1.4162

6 years

Añorga BridgeDuplex grade 1.4162

4 years

Millenium Bridge Duplex grade 1.4462

15 years

Puerto Arrupe BridgeDuplex grade 1.4362

12 years

Zumaia BridgeDuplex grade 1.4462

7 years

Cala GaldanaDuplex grade 1.4462

10 years

Note: No information about cleaning and mainternance done was available.

CRC = Corrosion Resistance Class (EN 1993-1-4 Annex A )

General information:- Year constructed: 2002 Location: Sweden- ISO 9223 Class: C3- Above channel, 255 ppm Cl- measured- Rain washed

Sicklauddsbron Pedestrian Bridge

10/30/2017This information is given in good faith and Outokumpu assume no liability for it 39

Materials:Forta DX 2205, beams, flange, handrail- Generally in good condition- Ra 4.0 µm316L, end cover tube of bridge cables- Good condition, some staining due to contamination304, brackets and stanchion- Overall in good condition but isolated pits can be observed

Orrhammarvägen Bridge Location: Flen, Sweden Structure type: Road bridgeCorrosion resistance class: CRC II, III Year of completion: 2009 (6 years)Distance from the salt water: ~60 km Local environmental notes: 8 ppm Cl- measured

Longitudinal beam web Longitudinal beam flangeGrade 1.4162

Longitudinal beam weldER 23 7 NL

Bridge bearing plateGrade 1.4162

Inspection date: 10/06/2015

Orrhammarvägen Bridge

Bottom of beam: Orange stain and contamination Small bolts: Poor condition. Galvanizing was visible on the bolt heads but not the shanks or nuts.

Welded areas: Some accumulation of dirt/dustBridge beams (Ra~5.0 µm): General appearance is in good condition


Sheltered condition Sheltered conditionSheltered condition

1.4162

Spectrum C O Mg Si K Ca Mn Fe TotalSpectrum 1 6.97 42.7 1.72 2.54 0.78 0.72 44.5 100Spectrum 2 8.31 40.6 2.42 2.57 0.93 0.67 0.68 43.9 100Max. 8.31 42.7 2.42 2.57 0.93 0.67 0.72 44.5Min. 6.97 40.6 1.72 2.54 0.78 0.67 0.68 43.9

Bottom of beam: Orange stain and contamination from mild steel after the surface finishing was applied (No chloride ion was found).

Orrhammarvägen Bridge

SEM/EDS-result


1.4162

Añorga Bridge

Handrail poleHandrail cable fittingHandrail tie plateGrade 1.4401

Bridge beam (Ra~8 µm)Grade 1.4162

Arch transition structure top surface (Ra~6 µm)Grade 1.4301

Arch transition structure side surfaceGrade 1.4162

Main arch Grade 1.4162

Arch weldER 23 7 NL

Location: San Sebastian, Spain Structure type: Railway bridgeCorrosion resistance class:Distance from the salt water:

CRC II, III~ 3 km

Year of completion: 2011 (4 years)


Añorga Bridge

Handrail pole, cable fitting and tie plateArch weld

Main arch


1.41621.4401

1.4401

Puerto Arrupe BridgeLocation: Bilbao, Spain Structure type: Footbridge / CyclewayCorrosion resistance class: CRC II, III Year of completion: 2003 (12 years)Distance from the salt water: ~10 km Local environmental notes: 2,400 ppm Cl- measured

Tubular handrailGrade 1.4401

Bridge box side surfaceBridge box finGrade 1.4362

Bridge box side surface at stairGrade 1.4362

Bridge box to fin weldER 22 9 3NL

FinWeld

Bridge box side surface at stair

Handrail

Fin

Fin

Wood


Puerto Arrupe Bridge

Bridge box side surface (Ra ~4 µm), welds and fin: Good condition

Bridge box surface in sheltered area: Some accumulation of dirt and staining. Discoloration is likely due to no washing, fabrication or transportation.

Bridge box side and fins: Orange stain → Fabrication (grinding, spatter from welding). No chloride ion was observed at this point (SEM/EDS)

Welds: Some scratch, dark spot from weld oxide and accumulation of dirt.


Open condition Sheltered condition Sheltered condition

1.4362

1.4362

Puerto Arrupe Bridge

Internal side surface and bridge box side surface at stair: Color painting to covering all scratches, vandalism, accidental contact with bicycles, dog urine, etc.,

Bridge box fins under surface at stair: Orange staining and discoloration

Bridge box fins (Ra 4 µm): Easy to trap water and some green organic matter was growing in this area.


Sheltered condition

1.4362

1.4362

Millennium Bridge

Bridge arch (Ra ~0.3 µm)1.4462

Cable fitting and boltSuspension cable1.4401

Balustrade infill framing1.4301

Handrail1.4401

Balustrade stanchionPainted carbon steel

Balustrade handrail1.4401

Bridge deck kurb1.4401

Location: York, UK Structure type: Pedestrian bridgeCorrosion resistance class: CRC II, III Year constructed: 2000 (15 years)Distance from the salt water: ~60 km Local environmental notes: 20 ppm Cl- measured


Millennium Bridge

Junction between arch and deck:Stain was noted.

Arch (Ra ~0.3 µm): Discoloration is more related to birds (some bird droppings) that evidently perch on the arch. No corrosion was observed.

Mesh frame (Ra~ 0.3 µm) and Infill mesh: Good condition

Handrail design: Easy to trap water and some green organic matter was growing in this area.

Cable: Good condition with some staining and debris were observed.


Open condition Sheltered condition1.4462

1.4462

1.4462

1.43011.4401 1.4401

1.4401

Millennium Bridge

Stanchions - vertical direction: Some staining

Handrail (circular section): Good condition

Fin at the northwestern side: Orange staining consistent with contamination from mild steel. No evidence of structurally concerning corrosion.

Horizontal direction (Ra~2.5 µm): Some staining


1.44011.4401 1.4401

1.4401

Painted carbon steel

Zumaia BridgeLocation: Zumaia, Spain Structure type: FootbridgeCorrosion resistance class: CRC III Year of completion: 2008 (7 years)Distance from the salt water: ~1 km Local environmental notes: 15,200 ppm Cl- measured


Zumaia Bridge

Bridge beamGrade 1.4462

Balustrade top surfaceGrade 1.4462WeldER 22 9 3NL

Bridge beam (Deck facing surface) Grade 1.4462

Balustrade infill bracketGrade 1.4462 Bolt headGrade 1.4401

Checker plate flooringGrade 1.4301

Balustrade end plateGrade 1.4462WeldER 22 9 3NL

WeldWeld

Stiffening angle under handrailGrade 1.4462

Handrail extension plateGrade 1.4462

Fiber glass

(Ra ~ 4 µm)


HandrailWood

Zumaia footbridge

Bridge beam

Balustrade top surface(Ra~5-6 µm)

• General appearance to be in good condition. • No chloride ion (SEM) was found on the surface.

Bridge beamBridge beam (Deck facing surface, Ra~4-5 µm)

Weld

Weld Weld

• Staining and discoloration was observed on the surface. • No corrosion attack were observed


1.4462

1.44621.4462

Zumaia footbridge

Orange stain on the dome nuts and under crevice area .

Balustrade top surface and end plate: Orange stain→ Fabrication (grinding) of carbon steel fence (handrail) beside the bridge

Weld oxide and heat tints


1.4462

1.4462

1.4401

Cala Galdana BridgeLocation: Menorca, Spain Structure type: Road and foot bridgeCorrosion resistance class: CRC IV/V Year of completion: 2005 (10 years)Distance from the salt water: < 250 m Local environmental notes: 17,300 ppm Cl- measured


Cala Galdana Bridge

Balustrade staunchion (Bracket plate and plate)Balustrade infill tube and hand railGrade 1.4462

Bridge deck main beamBridge deck outrigger beamGrade 1.4462

Bridge archGrade 1.4462

Bridge arch infill plateGrade 1.4462

Vehicle barrier tube Bracket base platePlateGrade 1.4401

Main bridge arch weldER 22 9 3NL

Vehicle barrier to arch transitionER 19 12 3 L

Bolt and nutGalvanized steel

Vehicle barrier bracket weldER 22 9 3NL


Cala Galdana Bridge

Main bridge arch, infill plate and weld: General appearance to be in good condition

Infill plate(Ra ~4-5 µm) Weld Weld

Weld

Balustrades (Ra 3-6 µm): Grey staining and discoloration was observed on the surface.


1.4462

1.4462

1.4462

1.4462

Cala Galdana Bridge

Fabrication: Some weld spatter was observed but did not cause any corrosion.

Fabrication: Orange staining at creviced associated with weld joint between two tubes

Bridge deck: Good condition. Staining from water run off

Bolt and nut: Red rust and corrosion


Sheltered condition Sheltered condition Sheltered condition1.4462

1.4462 1.4462

1.4401

Cala Galdana Bridge

1.4401

1.4462 1.4401

1.4462

1.4401

ER 22 9 3NL

ER 19 12 3 L

Galvanized steel


General information:- Year constructed: 2013 Location: Sweden- ISO 9223 Class: C2- Saline Bay, 3997 ppm Cl- in the water- Corrosion resistance class II or III in general depending on frequency of rain washing

Sölvesborg Pedestrian and Cycle Bridge

10/30/2017This information is given in good faith and Outokumpu assume no liability for it 60

Materials:Forta LDX 2101 on arch- Generally in good condition- Ra 3.0 µm316L hand rails, cable fittings- Some orange staining from contamination- Ra 3.0 µm

Resultat

• Fel: Kolstålsavskrap, kapskivesprut, svetssprut, dåligt betade svetsar, kolstålsskruvar, felstålsort

• Inget som påverkar funktionen.

• Materialvalen som gjorts i dessa fall kan bedömas som rätt och överenstämmer i principmed Eurocodereglerna.

• Det allmänna intrycket från inspektionerna är att broarna är i generellt gott skick.

• De flesta anmärkningarna kommer från kontaminering, fabrikation, transport eller“dagligt bruk”.

10/30/2017 62

Tack för uppmärksamheten!

Att välja material till bärande konstruktioner - SBI · Att välja material till bärande konstruktioner Hasse Groth & Thérèse Sterneland Avesta Research Center. Outokumpu. Älvsjö

Documents