Atlas of continuous cooling transformation (CCT) diagrams applicable to low carbon low alloy weld Metals (matsci

AN ATLAS OFCONTINUOUS COOLINGTRANSFORMATION (CCT)

DIAGRAMS APPLICABLE TOLOW CARBON LOW ALLOY

WELD METALS

AN ATLAS OFCONTINUOUS COOLINGTRANSFORMATION (CCT)

DIAGRAMS APPLICABLE TOLOW CARBON LOW ALLOY

WELD METALS

ZHUYAO ZHANG and R.A. FARRARDepartment of Mechanical Engineering

University of Southampton, U.K.,S0171BJ

THE INSTITUTE OF MATERIALS

Book 638Published 1995 by

The Institute of Materials1 Carlton House Terrace

London SW1 Y 5DB

© The Institute Materials 1995

ISBN 0901716944

Typeset, printed and bound byBourne Press LtdBournemouth, UK

An Atlas of CCT Diagrams Applicable to Low Carbon Low Alloy Weld Metals 1

I. Introduction

Since the pioneering studies on continuous cooling transformation (CCT) diagramscarried out by Christenson et al:' were published almost 50 years ago, many hundredsof CCT diagrams have been constructed throughout the world to describe the y-atransformation kinetics of most grades of commercial steels. Because most of themetallurgical processes occurring in steels involve continuous cooling before thefinal microstructure is obtained, the use of CCT diagrams to present the "I-atransformation reactions has obvious practical advantaget!smpared with othermethods such as the well-known time temperature transfor tion (TTT) diagrams.

The initial CCT diagrams were constructed for wrought steels and these cannotusually be directly applied to the cooling cycles experienced in welding situations.By employing modified reaustenitising procedures, the method was applied to theweld ability of steels and consequently, several CCT diagrams applicable to the coarsegrained region of the weld heat affected zones (HAZ) were published.r" However,since mid-1970s, increasing demands for weld metals of high toughness at lowtemperatures with the appropriate microstructures has produced the requirementfor a more systematic and detailed study of transformation kinetics and mechanicalproperties of low alloy weld deposits. This resulted in a number of CCT diagramswhich were directly applicable to weld metals and these have significantly improvedour understanding of weld metal microstructural development and the effects ofdifferent factors, such as chemical composition, oxygen content (thus size distributionand population of inclusions), welding parameters (e.g. cooling rate) and prioraustenite grain size, on the "I-a transformation behaviour of weld metals."?'

It is therefore of both practical as well as academic importance to draw togetheran atlas of CCT diagrams applicable to low carbon low alloy weld metals. It is hopedthat these diagrams will be of assistance to welding engineers, welding metallurgists,welding-consumables designers in industry. At the same time, they will also proveuseful to those in academia who are involved into investigations of steel weld metalphase transformation kinetics.

2. Microstructural terminology for low carbon low alloy weld metals

The microstructural constituents commonly found in low carbon low alloy welddeposits can be classified as follows, arranged in the order of decreasingtransformation temperature-A"

(1) Primary ferrite (or polygonal ferrite);(2) Ferrite side-plates (or Widmanstatten ferrite);(3) Fine grained acicular ferrite;(4) Lath structure (lath ferrite or bainite, or lath martensite).

Within the large number of investigations, however, there has been considerableinconsistency among various classification schemes used to define the different

2 An Atlas of CCT Diagrams Applicable to Low Carbon Low Alloy Weld Metals

transformation phases. It is therefore necessary to briefly compare these differentschemes. Table 1 summarises some earlier schemes used for low carbon low alloyweld metals.

Table 1. Review of microstructural terminology used for low carbon lowalloy steel weld metals, after The Japan Welding Society" and others.

CA. Dube28H. I. Aarronson29 JapaneseR. C Cochrane30 T. G. Davey31 D. J. Abson32 Others15, 25, 26,33-41 researchersta 42-49

Allotriomorphic Proeutectoid ferrite; Grain boundary Proeutectoid ferrite; Proeutectoid ferrite;(polygonal) ferrite; ferrite; Grain boundary Grain boundary

ferrite; ferrite.Polygonal ferrite; Polygonal ferrite;Blocky ferrite;

True grain boundaryPolygonal ferrite Ferrite islands. ferrite;

Polygonal ferrite.

Primary and Lamellar component Ferrite with aligned Ferrite sideplates; (Widmannstatten)secondary ferrite (product). MAC; Widmannstatten Ferrite sideplates;sideplates. Upper bainite. ferrite sideplates; Lath like ferrite.

Lath ferriteSide grain boundaryferrite.

Intragranular ferrite Acicular ferrite. Acicular ferrite; Acicular ferrite; Acicular ferrite.plates. Fine bainite ferrite. Needle-like ferrite;

Fine grained ferrite;Labelled intregranularferrite;Intragranular ferrite.

Massive ferrite; Granular ferrite.

Microphases

Pearlite; Ferrite-carbide Pearlite;aggregate;

Lath martensite; Martensite. Martensite; Martensite; Martensite;Twinned martensite; M-A constituent M-A constituent; M-A constituent;Retained austenite; Lath ferrite; High carbonUpper (occasionally Upper bainite; martensite;lower) bainite Lower bainite & Upper bainite.

Martensite

Efforts have been made by The International Institute of Welding (IIW) to developa standard scheme for the identification of ferritic weld metal microstructures.Y"Harrison and Farrar14,16,17 used a terminology similar to that of the IIW proposal, butalso considered the morphologies of various types of ferrite present in low carbonlow alloy welds. This allowed them to describe satisfactorily the microstructures inC-Mn and C-Mn-Ni weld metals. More recently, Zhang and Farrar21-24 employed a modified terminology which extended the Harrison and Farrarscheme. 14, 16, 17 Table 2 lists this terminology and the description for each constituentalong with the equivalent terminology 'proposed by the IIW. Some examples of thedifferent microstructures are illustrated in Fig.I.

An Atlas of CCT Diagrams Applicable to Low CarbonLow Alloy Weld Metals 3

Table 2. Definition of microstructural terms used by the currentauthors and the equivalent terminology under the IIW scheme. 22-32

Transformation product General description(Z. Zhang andR. A. Farrar22-24)

Equivalent terminology in IIWscheme

Polygonal fenite(PF) Polygonal or equiaxed at low cooling Primary ferrite (PF) or (PF(G»rates;Grain boundary allotriomorph at highercooling rates.

Pearlite (P) Pearlite or pearlitic carbides. Ferrite-carbide aggregate(FC(P»

Ferrite with non-aligned Ferrite completely surrounding eithersecond phase (FS(NA» (i) microphases which are

approximately equiaxed and randomlydistributed or (ii) isolated laths ofacicular ferrite.

Ferrite with non-alignedsecond phase (FS(NA»

Ferrite sideplates (FSP) Sideplate structures growing directly Ferrite with second phasefrom polygonal ferrite or grain boundary (FS(SP»allotriomorphs, i.e. Widmannstattensecondary sideplates.

Acicular ferrite (AF) Acicular ferrite (AF)

Coarse acicular ferrite(CAF)

Intragranular product of fineinterlocking ferrite grains separated byhigh angle boundaries, and aspect ratiofrom ,..,3:1-10:1.Refers to the intra granular productformed at slower cooling rates thanacicular ferrite with larger grain size andmay be associated with carbides.

Acicular ferrite (AF)

Lath ferrite (LF) Ferrite with second phase(FS(B»

Refers to a predominantly intragranularproduct resembling bainite whichsometimes forms amongst acicularferrite or sideplate structures.Carbides mayor may not be present.

Martensite (M) Lath martensite Martensite (M(L»

In this monograph, the terminology of most of the CCT diagrams will beessentially in line with the scheme of Table 2. However, the microstructuraldescriptions employed by some other authors, which are not clearly defined bythose authors, such as Homma et al." are respected and retained in their CCTdiagrams, and the equivalent terminology to these may be found either from Tablelor Table 2.

4 An Atlas ofCCT Diagrams Applicable to Low Carbon Low Alloy Weld Metals

a. PF andCAF

c.AF

e. FS(NA)

b.FSP

d. AF with PF an FSP

f.M

Fig. 1 Definitions of weld metal microstructural constituents used in CCT diagrams:(a) PF and CAF; (b) FSP; (c)AF; (d) AF with PF and FSP; (e) FS(NA); (f) M.


3. Construction of CCT diagrams for low carbon low alloy weld metals

Continuous cooling dilatometry technology is by far the most commonly usedmethod of producing CCT diagrams applicable to welding. In the case of steels, thetransformation temperatures for corresponding microstructural products can oftenbe obtained by locating the temperature at which the dilation versus temperaturecurves start to deviate from linearity. The CCT diagram can then be constructed byplotting temperature versus time. This procedure is shown schematically in Fig. 2.54

(a)

(b)

ee)

(d)

P, PsFs

TEMPERATURE ---+

LDGTlME -

Fig. 2 The normal procedure of producing a CCT diagram for steel."(a) Schematic length versus temperature plots for four different coolingrates; (b) schematic CCT diagram produced from data in (a).

Although for low carbon low alloy weld metals, especially at cooling ratesexperienced under welding conditions (typically 1-30 Ks-l, ~T 800-500 °C), thetransformed microstructure from the parent austenite (A) usually consists of differentforms of ferrite phase, i.e. polygonal ferrite (PF), ferrite side-plates (FSP), acicularferrite (AF) and sometimes lath ferrite (LF). These do not lead to a very cleardilatometric resolution (deviation from linearity) unless some martensite (M) forms.In these cases, quantitative metallography is used to locate the temperature at whicheach ferrite phase transforms. The transformation order of these ferritic structuresare known.P" and assuming that the contribution of each amount of transformationto the volume change of the sample is the same, it is possible to calculate the microstructural constituent start temperatures as shown in Fig. 3.54 The correspondingCCT diagram can then be constructed accordingly. This dilatometry-metallographymethod has recently been completely verified by Farrar and Zhang 55using systematicstep-quenching and detailed metallographic examination.


t

IIi

I~ozW-J

TEMPERATURE

Fig. 3 Construction to determine transformationtemperature for any percentage transformation.

The dilatometry method clearly has many advantages in constructing CCTdiagrams applicable to welding and CCT diagrams have been shown to be veryhelpful in studying weld metal transformation behaviour, in particular, themicrostructural development in reheated regions in multi-pass welds. However,the application of these CCT diagrams to real as-deposited weld are not withoutlimitations. The major problem is that this technique obtains transformation datafrom reheated weld metal rather than from the original deposit which hasexperienced the full solidification reaction. To overcome this limitation, someattempt" has been made to produce CCT diagrams for weld metals by directlyquenching the joint before the normal termination of the welding pass. Thetemperature-time data in this case was obtained from a thermocouple directlyplanted into the weld beads. The principal problem of this procedure lies in theaccuracy of matching the measured temperature with each precise microstructuralregion and the complicated nature of the technique in practice, These problemstherefore substantially limit the application of this direct quenching technique.

Most of the CCT diagrams included in this monograph were produced using thereheating dilatometry technique. There are, however, a few diagrams which wereproduced from the direct quenching technique.


Annotations: 1. In the CCT diagrams, 4.1.4-4.1.8, 4.2.13, 4.4.1, and 4.10.1 wereproduced by direct cooling method, whilst the rest of the diagrams wereconstructed using dilatometry technique.

2. In 4.1.4-4.1.8, 4.2.13, 4.4.1 and 4.10.1 diagrams, the grain size ofthe weld structures (i.e. average columnar grain width) were around1-600J1m respectively.

3. In the CCT diagrams, nd = not determined. NA = not available.

Acknowledgements

In this monograph, we have freely adapted the weld metal CCTdiagrams producedby many other researchers. We are grateful to these authors for their permission toallow these diagrams to be included in this atlas, which we believe will provide aneasy access to CCT diagrams applicable to low carbon low alloy weld metals, andwill therefore benefit welding industry and research. Particular thanks are due toall welding metallurgy research students who have worked at SouthamptonUniversity, for their enormous input of painstaking experimental work.



4. CCT diagrams applicable to low alloy weld metals

4.1 C-Mn

4.2 C-Mn-Ni

4.3 C-Mn-Ni-Mo

4.4 C-Mn-Mo

4.5 C-Mn-Nb

4.6 C-Mn-Si

4.7 C-Mn-Si-Ti

4.8 C-Mn-Si- Ti-B

4.9 C-Mn-Ti

4.10 C-Mn-V



Section 4.1

C-Mn



1200~------------------~------------~

• Dilatometry

o Metallography

Austenitised: 1400°C 10see

Grain size: ASTM 5.8

1000

800

~Q)

~1\1 600"-CDa.E

~

400 M

•

200Cooling rate800-500DC

Estimated

00.1 1

500(I) I(I)

---------_ IQJzl:a. 250 I~> I<U IJ: I

0

weldingwindow

10 100 1000 10000

Time, sec

Chemical composition of the weld metal (wt% )

4.1.1 C(O.06%)-Mn(O.7%) manual metal arc (MMA) weld (source: Harrision" and

Harrison and Farrar")


1200~--------------------------------~

800

o0

cD...::s

+'" 600asCDa.E

~

400weldingwindow

M

~

200

Cooling rateaoo-soo-c

--- Estimated

00.1 1

500enenQ)z

250CCl.,"E>caJ:

0

1000

Austenitised: 13S0°C 1Osee


10000

• Dilatometry

o Metallography

4.1.3 C(O.07%)-Mn(2.1%) MMA weld (source: Harriston" and Harrison andFarrar'")

10 100 1000

Time, sec

Chemical composition of the weld metal (wt %)


1,200~------------------------------~

• PF start

200

FSP II

o ",/'/"",--------"'"

1,000

800

0°CD:;.•... 600asCDa.E{E.

400I 0II

!

• FSP start

o Carbide start

----- Ferrite finish

a0.1 1 10 100 1,000 10,000

Time (800-500°C), sec

z 500I IIQ.. I

> I II Ien

250I II I

UJ - --t- II IQ)c: I II

.....,"0ns I II IJ: 0

Chemical composition of the weld metal (wt%)

c o004S 0.0126

4.1.4 C(O.05%)-Mn(1.45%) tungsten inert gas shielded (TIG) weld (source:

Kenny, Kerr, Lazor and Graville")


1,200 ,-------------------,

1,000

800

0°a>L..

:::s•... 600as~CDa.E

~

400

IIIIIII,IIIII • PF start

• FSP start

• IG SFP start

o Carbide start

.---- Ferrite finish

200

o~------~------~------~------~------~0.1 1 10 1,000100

Time (800-500°C), sec500~----~'--~I~!~I----!--~i~--------~

- - -t---tW--lJ' I I I: 'I I II I II I I I I II I I I I Io ~ ~I~ __ ~I_~I~I __ ~l~ __ ~l ~


10,000

0.0087

c0.11

o

4.1.5 C(O.11%)-Mn(2.10%) TIG weld (source: Kenny, Kerr, Lazor and Craville")


1,200~------------------------------~

• PF start

A AF start

• FSP start


200

1,000

800

Q)•....:l•..es•....Q)Q.

E~

600 AF+FSPI

I

//

--,'"..-------,"'...-

400

o~----~------~------~------~------~0.1 1 10 100 1,000 10,000

Time (800-500°C), sec

500 I I I I I, :I J I II I I I t I

---~, IIill~t I I I' I ,II t I I

(I)

enQ)zC:Q. 250~'E>coJ: o


c o0.08 0.08S0

4.1.6 C(O.08%)-Mn(1.2S%) flux cored wire (FCW) weld (source: Kenny, Kerr,Lazor and Craville")

An Atlas ojCCY Diagrams Applicable to Low Carbon Low Alloy Weld Metals 19

1,200 ,.----------------------.

• PF start

• FSP start

A. AF start

• IG FSP start

200

PF

1,000

800

0°q)L-

::Jas 600L-ena.E{!

400

iII

,/r=:':/II

.- - - _. Ferrite fin ish

00.1 1 10 100 1,000 10,000

Time (800-500°C), sec

500 I 1 J I :(I) I(I) I I I I I4)z 250 - - --r--t--+-+--JCo.'E> I Ica I I I I I:I:

0 J I I J I


c o0.08 0.0110

4.1.7 C(O.08%)-Mn(1.48%) FCW weld (source: _~enny, Kerr, Lazor and Craville")


1,200~------------------------------~

800

200• PF start

• FSP start

A AF start

1,000

CD~::J1ii 600~CDa.E

~

400


o~----~------~------~------~------~0.1 1 10 100 1,000 10,000

Time (800-S000e), sec500 I: I I I :

I I I I I I---~I i I I

I I --r--t-t----4I I I I I Io~----------_I~I--~I--I~~I_~I------------~


c o0.12 0.0360

4.1.8 C(0.12%)-Mn(1.41 %) FeW weld (source: Kenny, Kerr, Lazor and Craville")


1,200~------------------------------~

1,000

Austenitised: 1350°C 1sec

Grain size: NA

800

oo

0>L..

::J1U 600CDa.Et!

400

200Cooling rate

aoo-soo-c

o~------~------~------~------~------~0.1 1 10 100 1,000

Time, sec

2 500 I I : , I I ; IQ. I I I I

> ----------~':: I: : I~ 250 - I , I I I I.§ I I I Icu I I I I I I I I:I: 0 I I I I I I I 1


10,000

4.1.9 C(O.09%)-Mn(l.35%) submerged arc (SA) weld (source: Homma, Ohkita,

Matruda and Yamamoto")


1,200~------------------------------------~


Grain size: approx. 100llm

1,000 ~

800-~

PF00

AF-'~ai~•.. 600-asCDa.E{E

400~

200~

o~------~------~------~------~----~0.1

• PF start

• AF start

• Ferrite finish

I I I I

1 10 100 1,000 10,000

Time (800-500°C), sec


c Mn N o0.049 0.68 0.0073 0.1132

4.1.10 C(O.05%)-Mn(0.68%) Metal arc inert gas shielded (MIG) weld (source:

Bannister")


1,200 ~------------------,

1,000 -

Austenitised: 13S0°C 10see

Grain size: approx. 100J]m

800~ ...----...-U0 PFa)•...

~

:la; 600~ AF•...Q)a.E

~

400---

200 r-

O~------~------~------~------~------~0.1

• PF start•. AF start

• Ferrite finish

I 1 I I

1 10 100 1,000 10,000

Time (800-500°C), sec


c o0.0447 0.0447

4.1.11 C(O.05%)-Mn(O.69%) MIG weld (source: Bannister")


• PF start

£. AF start

• Ferrite finish

I I I I

1 10 100 1,000 10,000

Time raoo-soo-ci, sec

1,200~------------------------------~


Grain size: approx. 100pm

1,000r-

800 r-

~0

AF-+~

a

cD:5as 600 f-a;a.E

~

400 r-

200 r-

o~------~------~------~------~------~0.1


N

0.1140

c Mn

0.00530.049 0.69


o


1,200~--------------------------------~

200 • PF start

.•. AF start

• Ferrite finish

°0.1 1 10 100 1,000 10,000Time (800-500°C), sec


Grain size: approx. 100Jlm

1,000

800

o.>;:

°0>AF-+~

~:::J.•.. 600as~Q)0-E{E.

400


c Mp N 9

0.043 0.98 0.0308 0.0657



1,200 ,...----------------------,

1,000

Austenitised: 1350°C 1Osee


800~

0 PF°a> AF7'•..:Jas 600•..Q)Q.

E{!

400

200 • PF start

~ AF start

• Ferrite finish

00.1 1 10 100 1,000 10,000

Time (800-500°C), sec

Chemical composition of the weld metal (wt % )

N

0.0663

c Mn

0.01120.049 1.58

4.1.14 C(O.Os%)-Mn(1.S8%) MIG weld (source: Bannister")

o


1,200~--------------------------------~


Grain size: approx. 100J,lm

1,000 ~

800~

0~0

0) ..:; *-. -*-"Tas 600~AF~CDa.

E{!

400~

200~

o~------~------~------~------~------~0.1

• PF start

A AF start

• Ferrite finish

I I I I

1 10 100 1,000 10,000

Time (800-500°C), sec


c o0.02 0.0539

4.1.15 C(O.04%)-Mn(1.30%) MIG weld (source: Bannister")


200 • PF start

~ AF start

• Ferrite finish

00.1 1 10 100 1,000 10,000

Time (800-S00°C), sec

1,200~--------------------------------~

1,000


Grain size: approx. 100JIm

800

0 ~° PF0)a-::J *"T.•...•

600asAF~a-

0)C.E

{E.

400


c0.03070.07

4.1.16 C(O.07%)-Mn(1.36%) MIG weld (source: Bannister")

o


1,200~--------------------------------~

1,000



800

0~°0>•... ...::J ... * *otJ 600as

AF~•...0)a.E{Eo

400

200 • PF start

.6. AF start

• Ferrite finish

00.1 1 10 100 1,000 10,000

Time (aOO-SOOOe), sec


N

0.0779

c0.0089

~n0.069 .51

4.1.17 C(O.07%)-Mn(l.Sl %) MIG weld (source: Bannister")

o


1,200 .---------------------.

1,000


Grain size: approx. 100Jlm

800

0 ~°a> .& a.t. • ..•••...::1•. 600 AF

~as•...Q)a.E

~

400

200 • PF start

A. AF start

• Ferrite finish

00.1 1 10 100 1,000 10,000

Time (800-500°C), sec


0.0438

c0.08

4.1.18 C(0.08%)-Mn(1.S3%) MIG weld (source: Bannister")

o


1,200~--------------------------------~

800-



1 ,OOO~

o°

400~

200~

o~------~------~------~------~------~0.1

• PF start

~ AF start

• Ferrite finish

I I I I

1 10 100 1,000 10,000

Time (800-500°C), sec


c~n

N o0.078 .s3 0.OOS2 0.0462

4.1.19 C(O.08%)-Mn(1.S3%) MIG weld (source: Bannister")


200 • PF start

'" AF start

• Ferrite finish

00.1 1 10 100 1,000 10,000


1,200~------------------------------~

1,000



800~

0 PF°0)

AF~:;10 600CD0.E{!

400


c N

0.07000.035

4.1.20 C(0.04%)-Mn(1.60%) MIG weld (source: Bannister")

o


Section 4.2

C-Mn-Ni



1200~--------------------------------~

800

o0

cD:5•.. 600asCDa.E ,,"

~ "< LF+AF,,,400 ,, •

"M

• •200

Cooling rate800-500°C

--- Estimated

00.1 1

1000

Ausrenitised: 1350°C 1Osee


weldingwindow

• Dilatometry

o Metallography

10 1000 10000100Time, sec

500 ------------~I-----------~I--~!I----~I~I~-I~I ------~I I I I ~ I

----- I : I I I I~ ----rr-----.------.+I __ ~l -l ~ !I I I -r-t---J: :! l I !

250

oChemical composition of the weld metal (wt %)

4.2.1 C(O.05%)-Mn(O.98%)-Ni(O.06%) MMA weld (source: Harrison" and



1200~--------------------------------~

1000

800

o0

cD~::J+-I 600esCDa.E{E. --------

400M

200

Austenitised: 13S0°C 1Osee


o~------~------~--------~------~------~0.1

• ••

welding

window

~

Cooling rateaOO-SOOaC

--- Estimated

• Dilatometry

o Metallography

1 100 100010

Time, secz 500Q.

> ---- ----.en250U)

GIC

"0a;:x:

0


10000

4.2.2 C(O.05%)-Mn(1.68%)-Ni(O.95%) MMA weld (source: Zhang-' and Farrar

and Zhang23)


1200~---------------------------------'

800

~cD:5•... 600asCDa.E{Eo

400 M

,,/,

.... ""-----,... ..•

200Cooling rate Msoo-soo-c

--- Estimated

00.1 1

z 500Q..

> -------ui250In

CItc:"EasJ: 0

1000

Ausrenitised: 1350°C 10seeGrain size: ASTM 5.5

10000

weldingwindow

4.2.3 C(O.04%)-Mn(1.20%)-Ni(1.lO%) MMA weld (source: Harrison14 andHarrison and Farrar")

• Dilatometry

o Metallography

10 1000100Time, sec



1200~----------------------------~

800

00

Gi•...::s.•... 600as•...Q)a.Et!

400M

200Cooling rate

BOO-SOOGC

---- Estimated

00.1 1

500tntnQ)z

250Cc..'E>cUJ:

0

1000


Grain size : ASTM 5.50

weldingwindow

~

• Dilatometry

o Metallography

10 10000100 1000Time, sec


4.2.4 C(O.04%)-Mn(1.67%)-Ni(2.48%) MMA weld (source: Zhang'? and Farrar

and Zhang23)


1200~------------------------------~

1000



800

o0

0)t-:::sas 600t-O)a.E~

400M

weldingwindow

~

• Dilatometry

o Metallography

10 100 1000 10000

200

Cooling ratesoo-soo-cEstimated

·00.1 1

500(I)CI)

4Jz

250C:o."E>cuJ:

0

Time, sec


4.2.5 C(O.05%)-Mn(1.18%)-Ni(2.52%) MMA weld (source: Harrison" and



1200.---------------------------------~

800

00

~:::J+J 600CdOia.Ee -...-----

400M

-------_/•200

Cooling rateBOO-500DC

._- Estimated

00.1 1 10

1000



CAF

weldingwindow

• Dilatometry

o Metallography

100 1000Time, sec

2 500Q.. I I> -----~ ..iii 250(/)

CDc-a~:I: 0


10000

4.2.6 C(0.04%)-Mn(O.85%)-Ni(2.56%) MMA weld (source: Zhang" and Farrar

and Zhang")

1200~----------------------------~An Atlas of CCT Diagrams Applicable to Low Carbon Low Alloy Weld Metals 41

1000



200

800

00

cD:5.•.. 600(\1'-Q)a.E{J1

400 weldingwindow

Cooling rateaOO-500°C • Dilatometry

o Metallography--_. Estimated

o~------~------~--------~------~------~0.1 1 10 100 1000

Time, sec(/)(/)

CUzCo.."E>lUJ:


10000

4.2.7 C(O.06%)-Mn(O.67%)-Ni(3.32%) MMA weld (source: Zhang" and Farrarand Zhang23)


1200~----------------------------~

800

o0

cD:;as 600CDa.E~

400 •M ~• welding

• ~ window

~

•

~200Cooling rate • Dilatometry800-500°C

Estimated 0 Metallography

00.1 1 10 100 1000 10000

Time, sec500

C1)C1)

"'z 250Ca.."E>co:I: a

1000




4.2.8 C(O.04%)-Mn(1.29%)-Ni(3.S8%) MMA weld (source: Harrison" and



1200~----------------------------~

800

o0

cD:5a; 600•...Q)a.Ef2

•400 AF+LF iM

weldingwindow

200Cooling rate

Dilatometryaoo-soo-c •Estimated

o Metallography

00.1 1 10 100 1000 10000

Time, sec500

(I)(I)

CUz 250c~"E>co::I: 0


1000



4.2.9a C(O.OS%)-Mn(O.78%)-Ni(S.S3%) MMA weld (source: Farrar, Zhang,

Bannister and Barritte" and Zhang")


1200~------------------------------~

800

00

cD•..::3•.. 600as•...Q)0-E{!

400 AF+LF

200


--_. Estimated

00.1 1

500(t)(I)

Q)zCo. 250~>"'J:

0

1000

Austenitised: 1350°C 85secGrain size: ASTM 2.87

M

weldingwindow

• Dilatometry

o Metallography

10 100 100001000Time, sec


4.2.9b C(O.Os%)-Mn(O.78%)-Ni(S.S3%) MMA weld (source: Farrar, Zhang,Bannister and Barritte" and Zhang")


1200~--------------------------------~

1000


800

o0

~~•.. 600asI-

ma.E{E.

400M

200welding OOOOC\l=

window lKJCooling rateaOO-500°C • Dilatometry

o Metallography---. Estimated

o~------~--------~------~--------~------~0.1 1 100 100010

Time, sec

500 r I I I I I !

250 :--------------:--H--LLJjI I I I I I II I I I I I I

a ~------------------.I--~II--~I--~I~-~I~I--------~Chemical composition of the weld metal (wt%)

10000

4.2.9c C(O.05%)-Mn(O.78%)-Ni(5.53%) MMA weld (source: Farrar, Zhang,

Bannister and Barritte" and Zhang")


1200r---------------------------------~

800

00

~::J•...

600as~Q)0..

E{E.

400M

200Cooling rateBOO-SOO°C

a0.1 1

500"GOCUzCo. 250~>ftIl:

0

1000

Austen itised: 1350°C 1OseeGrain size: ASTM 5.06

10000

• Dilatometry

o Metallography

4.2.10 C(0.08%)-Mn(0.96%)-Ni(O.90%) TIC weld (source: Zhang" and Farrar and

Zhang")

10 100 1000Time, sec



1200.---------------------------------~

1000

- - - Esti mated

800

o0

cD...::l«1 600'-Q)c.E

~

400 M

200Cooling rateaOO-500°C


• Dilatometry

o Metallography

O~----~~----~------~-------L------~0.1 1 100 100010

Time, sec


10000

4.2.11 C(O.08%)-Mn(1.33%)-Ni(O.73%) TIG weld (source: Zhang22)


1200~------------------------------~

1000

---- Estimated

800

o0

a)~.. 600asL-

CD0..

Et!

400 M

200Cooling rateaOO-500°C

Austenitised: 1350°C 1OseeGrain size: ASTM 5.06

• Dilatometry

o Metallography

o~------~------~--------~------~------~0.1 1 100 100010

Time, sec


10000

4.2.12 C(O.10%)-Mn(O.89%)-Ni(1.2S%) TIG weld (source: Zhang22)


1,200~------------------------------~

1,000

800

0°a>:s

PF+FSPas 600'-Q)a.EfE.

400

• PF start

• FSP start

200 .A. IG FSP start

0 Carbide start


o~------~------~------~------~------~0.1 1 10 100 1,000 10,000

Time (800-500°C), sec


c Mn o0.09 1.61 0.0072

4.2.13 C(O.09%)-Mn(1.61%)-Ni(2.0%) TIG weld (source: Kenny, Kerr, Lazor and, Craville")


1200~------------------------------~

200Cooling rateaOO-50ODe

00.1 1

500(/I(/I4IzCQ. 250'E>tU:r:

0

1000

800

oo

cD:;~ 600CD0.E

~

400

Austenitised: 1350DC 10secGrain size: ASTM 4.92

o

~CAF+(M-A)

M

• Dilatometry

o Metallography

10 100 100001000Time, sec


4.2.14 C(0.07%)-Mn(1.26%)-Ni(2.25%) TIG weld (source: Zhang" and Farrar and

Zhang")


1200~----------------------------~

800

00

~:J•.. 600«1~CDc.E

{Eo

400M

200Cooling rate

800-500°C

00.1 1

500f)f)

4»z 250c:~'E>«IJ:

0

1000

Austenitised: 1270°C/sec


• Dilatometry

o Metallography

10 100 1000 10000Time, sec


4.2.15 C(O.09%)-Mn(l.05%)-Ni(3.32%) TIG weld (source: Zhang" and Farrar andZhang24)


1,200~------------------------------~

1,000

Austenitised: 1350°CGrain size: NA

800

o°0>~.•... 600asCDa.E

{E-

M400

200

o~------~------~------~--------~----~0.1 1 10010 1,000

Time (800-500°C), sec

z 500a..>en

250 -II)Q)c"ECGJ: 0

: I : I lI I I I I

___ ~III II I I I II I I II I I I II I I I I


10,000

4.2.16 C(O.06%)-Mn(1.40%)-Ni(O.14%) submerged fluxcored arc (SFCAW) weld(source: Kluken, Onsoien, Akselsen and Rorvik")


1200~----------------------------~

Ms = 447°C

Mf = 335°C

200

Austenitised: 1350°C

Grain size: NA

1000

800

0°cD~:J•... 600as~CDc.E

~

400 M

o~------~------~------~------~------~0.1 1 10 100 1000 10000



4.2.17 C(O.06%)-Mn(1.55%)-Ni(2.00%) SFCAW weld (source: Kluken, Onsoien,Akselsen and Rorvik")



Section 4.3

C-Mn-Ni-Mo



1200~--------------------------------~

800

0ocD...:l+-' 600ca...Q)a.E

~

400M

weldingwindow

[!]200

Cooling rate • Dilatometry800-500°C o Metallography

a0.1 1 10 100 1000 10000

Time, secz 500e,>u;

250CDCDC"0as~ 0

1000

Austenitised: 1350°C 10seegrain size: ASTM 5.38


4.3.1 C(O.06%)-Mn(1.s%)-Ni(1.0%)-Mo(O.2S%) MMA weld (source: Zhang22)


1200~------------------------------~

200Cooling rate800-500°C

Estimated

00.1 1

500(t)fI)

Q)zCo.. 250'E>C'CIJ:

a

1000

800

00

Q)L-~•.. 600asL-

CDa.E{!

400


Mweldingwindow

• Dilatometry

10 100 100001000Time, sec


4.3.2 C(O.05%)-Mn(l.72%)-Ni(l.87%)-Mo(O.31 %) MMA weld (source:Harrison")


1200~----------------------------~

200

Cooling rateaOO-50ODe

00.1 1

500tI)tI)CUz

250CQ."E>tUJ:

0

1000

800

0

0a):5.•.. 600asCDc.E

~

400

Austenitised: 1350DC 1Osee


M

welding ~_----,window \2°C/sec I

• Dilatometry

o Metallography

10 1000 10000100Time, sec


4.3.3 C(O.06%)-Mn(1.7s%)-Ni(2.73%)-Mo(O.20%) MMA weld (source:Zhang22)



Section 4.4

C-Mn-Mo



1,200~------------------------------~

• PF start

• FSP start

o Carbide start


200

1,000

800

0°0>~:l•... 600co~CDa.E{E.

400

00.1 1 10 100 1,000 10,000


z 500 II r I I IQ., --~>,n 250 •... I I I I I." I IGIC I I I I I I't:J«i : : I : : ~J: 0

Chemical composition of the weld metal (wt%)c o

0.11 0.0094

4.4.1 C(O.11%)-Mn(1.S0%)-Mo(O.3%) TIG weld (source: Kenny, Kerr, Lazor andCraville")



Section 4.5

C-Mn-Nb

66 An Atlas of CCT Diagrams .Applicable to Low Carbon Low Alloy Weld Metals


1200~----------------------------~

1000

800

00

~::las 600~(I)a.E{!!.

400

200



Carbide start.:--- -~J-~o~--~~~~'~t ~

AF\Xe1 :~!~~;\

• ~ ~CD

~/ ~--------------~~~ ~

M


Estimated

• Dilatometryo Metallography

• Thermal analysis

o~------~------~--------~------~------~0.1 1 100 1000010 1000

z 500~ ~------------~

Time, sec

! 250c~:z:


4.5.1 C(O.09%)-Mn(1.32%)-Nb«O.Ol%) MMA weld (source: Harrison, Watsonand Farrar" and Harrison")


1200~--------------------------------~

1000



4.5.2 C(O.lO%)-Mn(l.37%)-Nb(O.03%) MMA weld (source: Harrison, Watsonand Farrar" and Harrison")


1200~------------------------~--~

1000

800

o0

cDL-

::la; 600L-Q)c.E~

400

200

Austenitised: 1400°C 10seeGrain size: ASTM 5.1

Mweldingwindow

".'~"",,""" Q)_- U)-------------- g

Cooling rateeoo-soo-cEstimated

• Dilatometry

o Metallography

9 Thermal analysis

00.1 1 10 100 1000 10000

Time, sec

2 500Q.

>,,;250fA

CDc:'E••J:

0


4.5.3 C(O.09%)-Mn(1.05%)-Nb«O.Ol%) MMA weld (source: Harrison, Watsonand Farrar" and Harrison")


1200~------------------------------~

800

o0

0)~::l•.. 600asCDa.E{E.

400M

",,/----------*""'-'200


Estimated

00.1 1

z 500Q.

>0 250'"atI:

"0•X 0

1000


weldingwindow

• Dilatometry

o Metallography

o Thermal analysis

10 100 1000 10000

Time, sec


4.5.4 C(0.08%)-Mn(0.97%)-Nb(O.02%) MMA weld (source: Harrison, Watsonand Farrar" and Harrison")


Section 4.6

C-Mn-Si



1200~--------------------------------~

1000


Grain size: NA

800

oo

cD~::J~ 600Q)a.E~

400M

200

O~------~------~------~-------L------~0.1 1 100 100010

Time (from Ac3), sec


10000

4.6.1 C(O.09%)-Mn(O.81 0/0)-Si(O.110/0)MIG weld (source: Ito, Nakanishi andKomizo")

74 An Atlas ofCCY Diagrams Applicable to Low Carbon Low Alloy Weld Metals

1200


Grain size: NA

1000

Ac3 = snoc

800

00

ai•...::l•.. 600as•...Q)Co

E~

400

200

00.1 1 10 100 1000 10000

Time (from Ac3). sec


C Mp I Si I S I p I Cu I N 0

0.11 0.14 0.09 0.013 0.016 0.12 0.0050 0.010

4.6.2 C(0.11%)-Mn(O.74%)-Si(O.09%) MIG weld (source: Ito, Nakanishiand Komizo")


Section 4.7

C-Mn-Si-Ti



1200~--------------------------------~

800Ac1 = 717°C

00

Q):s•.. 600as••...Q)a.E

~

400

1000

200


Grain size: NA

Ac3 = 910°C

o~------~------~------~------~------~0.1 1 100 1000 1000010



4.7.1 C(O.11%)-Mn(1.09%)-Si(O.40%)-Ti(O.05%) MIG weld (source: Ito, Nakanishi

and Komizo'")


1200


Grain size: NA

1000Ac3 = 8B6°C

800Ac1 = 70BOC

00

CD:5•.. 600asQ)a.Et!

400

200

o~------~------~------~------~------~0.1 1 10 100 1000 10000



4.7.2 C(O.12%)-Mn(O.80%)-Si(O.2s%)-Ti(O.027O/o) MIG weld (source: Ito,Nakanishi and Komizo")


Section 4.8

C-Mn-Si- Ti-B



1200


Grain size: NA

1000

Ac3 = 877°C

800Ac1 = 708°C

00

cD~::J.•.. 600asGia.E

~

400M

200

o~------~------~------~------~------~0.1 1 100 100010



10000

4.8.1 C(O.11% )-Mn(O.960/0)-Si(O.220/0)-Ti(O.029% )-B(O.0026%) MIG weld (source:

Ito, Nakanishi and Komizo")


1200~--------------------------------~

1000

800

00

cD'-::l.•..• 600as'-Q)a.E{Eo

400

200


Grain size: NA

o~------~------~------~------~------~0.1 1 10010 1000 10000



4.8.2 C(O.09% )-Mn(l.lO% )-Si(O.27O/o)- Ti(O.038% )-B(O.0027O/o) MIG weld (source:Ito, Nakanishi and Komizo")


1200


Grain size: NA

1000Ac3 = 88SOC

800

00

a>•...::l•... 600asCiic..E

~ .....

400M

200

00.1 1 10 100 1000 10000

Time (from Ac3), secz 500Q.

>vi 250II)CDc'ECIIX

O!Chemical composition of the weld metal (wt %)

4.8.3 CeO.1I °/0)-Mn(I.16°/0 )-Si(O.29°/0)- Ti(O.043°10)-B(O.0034 °/0) MIG weld (source:Ito, Nakanishi and Komizo")



Section 4.9

C-Mn-Ti



1,200Austenitised: 1350°C 1sec

Grain size: NA

1,000

Ac3 = 862°C

800

00

0)~::l.. 600as~CDc.E{!

400

200

Cooling rateeoo-soo-c

00.1

z 500Q..>g)

2500)CDc'0:ax 0

Q,;89 Mn1.43

1 10 100 1,000

Time, sec


10,000

4.9.1 C(O.089%)-Mn(1.43%)-Ti(O.028%) SA weld (source: Homma,Ohkita,

Matruda and Yamamoto")



Section 4.10

C-Mn-V



1,200 r-----------------------,

00.1 1 10 100 1,000 10,000

Time (800-500°C), sec

z 500 J 1 I -r Ia. --l++-LJ> I I I I I0 250 - r r II/)CJ) I I ,cL) I 1 I I I:uI 0 I : III

1,000

800

o°

400

200

~ AF start

• PF start

• FSP start



0.0099c Mn

0.095 1.62o

4.10.1 C(O.095%)-Mn(1.6%)-V(O.1%) TIG weld (source: Kenny, Kerr, Lazor andGraville")



References

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2 C.L.M. COTTRELL,,. Iron Steel Inst., 174 (1953), p17.

3 E.F. NIPPES,W.F. SAVAGEand R.T. ALLIO,Weld. J. Res. Suppl., 36 (1960), p40.

4 M. INAGAKIand H. SEKIGUCHI,Trans. Natl. Res. Inst. Met. (Ipn), 2 (1960), p40.

5 F. WATKINGSONand R.G. BAKER,Br. Weld. f., 14 (1967), p603.

6 A. BROWNINGand R. BOELEN,IIW Doc., IIW-1976-MTC, 1976.

7 H. SEKIGUCHI,in Fundamental Research on the Welding Heat-Affected Zone of Steel,The Nikkan Kogyo Shimbum Limited, Tokyo, 1976.

8 K. YAMAMOTO,S. MATSUDA,T. HAZE,R. CHIJIIWAand H. MIMURA,in Proc. Con!Residual and Unspecified Elements in Steel, Edited by A.S. Melilli and E.G.Nisbett, Bal Harbour, FL, Nov. 1987, American Society for Testing and Materi-als, Philadephia, 1989, pp. 266-284.

9 D.J. ABSONand R.E. DOLBY,Weld. Inst. Res. Bull., 19 (1978), pp. 202-207.

10 D.V. DORLING,P.E.L.B. RODRIGUESand J.H. ROGERSON,in Proc. Can! Trends inSteels and Consumables for Welding, London 13-16 Nov. 1978, The WeldingInstitute, Abington, p351.

11 P.L. HARRISON,M.N. WATSONand R.A. FARRAR,Welding and Metal Fab., 49(1981), pp. 161-169.

12 G.S. BARRITTE,PhD Thesis, Cambridge University, 1982.

13 Y. ITO,M. NAKANISHIand Y. KOMIZO,Metal Constr., 14 (1982), pp. 472-478.

14 P.L. HARRISON,PhD Thesis, University of Southampton, 1983.

15 B.G. KENNY,H.W. KERRand B. GRAVILLE,Metal Constr., 17 (1985), pp. 374R-381R.

16 P.L. HARRISONand R.A. FARRAR,Metal Constr., 19 (1987), pp. 392R-399R.

17 R.A. FARRARand P.L. HARRISON,Metal Constr., 19 (1987), pp. 447R-450R.

18 S.R. BANNISTER,PhD Thesis, University of Southampton, 1987.

19 H. HOMMA,S. OHKITA,S. MATSUDAand K. YAMAMOTO,Weld. f. Res. Suppl., 66(1987), pp. 301s-309s.


20 A.O. KLUKEN,M.I. ONSOLEN,O.M. AKSELSENand G. RORVIK,Joining Science, 1(1991), pp. 14-22.

21 R.A. FARRAR,ZHUYAOZHANG,S.R. BANNISTERand G.S. BARRITTE,J. Mater. Sci., 28(1993), pp. 1385-1390.

22 ZHUYAOZHANG,PhD Thesis, University of Southampton, 1994.

23 R.A. FARRARand ZHUYAOZHANG,in Proc. 6th International Conference of Joiningof Materials, The European Institute of Joining of Materials, 4-6 April 1993,Helsingor, Denmark, pp. 397-404.

24 R.A. FARRARand ZHUYAOZHANG,in Proc. 2nd European Conference on JoiningTechnology, Italian Institute of Welding, 16-18 May 1994, Florence, Italy, pp.169-179.

25 C.L. CHOLand D.C. HILL, Weld. J. Res. Suppl., 57 (1978), pp. 232s-236s.

26 0. GRONGand D.K. MATLOCK,Inter. Metal Rev., 31(1986), pp. 27-48.

27 COMMITTEEOFWELDINGMETALLURGYOFJAPANWELDINGSOCIETY,1983, IIW Doc.,IX-1282-83.

28 C.A. DUBE,H.I. AARONSONand R.F. MEHL,Rev. Met., 55 (1958), p201.

29 H.I. AARONSON,The Decomposition ofAustenite by Diffusional Processes, Editedby V.F. ZACKAYand H.I. AARONSON,Interscience, New York, 1952, p389.

30 R.C. COCHRANE,CEGB Report T/PDM/46211/77.C.

31 T.G. DAVEYand D.J. WIDGERY,IIW Doc., IIA-389-76, 1976.

32 D.J. ABSONand R.E. DOLBY,'A Scheme for the Quantitative Description ofFerritic Weld Metal Microstructures', IIW Doc., IXJ-29-80.

33 R.J. PARGETER,IIW Doc., IXJ-37-80, 1980.

34 M.N. WATSON,P.L. HARRISONand R.A. FARRAR,Welding and Metal Fabr., 49(1980), pp. 101-108.

35 E. LEVINEand D.C. HILL,Metal Constr., 9 (1977), pp. 346-353.

36 E. LEVINEand D.C. HILL,Met. Trans., A8 (1977), pp. 1453-1463.

37 J.M. SAWHILL,Climax Moly., Rep. No. L176-115, 1973.

38 A.G. GLOVER,J.T. McGRATH,M.J. TINKLERand G.e. WEATHERLY,Weld. J. Res.Suppl., 56 (1977), pp. 267s-273s.

An Atlas ofCCY Diagrams Applicable to Low Carbon Low Alloy Weld Metals 95

39 A.J. PACEYand H.W. KERR, Welding and Metal Fabr., 46 (1978), pp. 613-615.

40 D.J. ABSON,R.E. DOLBYand P.H.M. HART,in Proc. Conf Trends in Steels andConsumables for Welding, London, 13-16 November 1978, The Welding Insti-tute, Abington, Paper 25.

41 L-E. SVENSSON and B. GRETOFT,Weld. J. Res. Suppl., 69 (1990), pp. 454s-461s.

42 Y. ITOand M. NAKANISHI,Yosetsu Gakkaishi, 44 (1975), p728.

43 Y. ITOand M. NAKANISHI,Yosetsu Gakkaishi, 44 (1975), p81S.

44 N. WTABABEand K. KOJIMA,Yosetsu Gakkaishi, 49 (1980), p772.

45 N. Mont, H. HOMMA,S. OHKITAand M. WAKABAYSHI,IIW Doc., IX-1196-81, 1981.

46 Y. Krr<UTA,T. ARAKIand M. YONEDA,Zairyo, 29 (1980), p556.

47 Y. KIKUTA,T.ARAKI,M. YONEDA,M. YOSHIDAand H. KABATA, IIW Doc., IX-1162-80, 1980.

48 Y. ITO,M. NAKANISHIand Y. KOMIZO,Yosetsu Gakkaishi, 50 (1981), p1211.

49 Y. ITO,M. NAKANISHIand Y. KOMIZO,Yosetsu Gakkaishi, 51 (1982), pl l l.

50 "Guidelines for Classification of Ferritic Steel Weld Metal MicrostructuralConstituents Using the Light Microscope', IIW Doc., (1983) IXJ-78-83.

51 'Guidelines for Classification of Ferritic Steel Weld Metal MicrostructuralConstituent Using Light Microscope', IIW Doc., (1985) IX-1377-85.

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53 'Guide to the Light Microscope Examination of Ferritic Steel Weld Metals',IIW Doc., (1988) IX-1533-88/IXJ-123-87 Revision 2, June 1988.

54 P.L. HARRISONand R.A. FARRAR,Inter. Mater. Rev., 34 (1989), pp. 35-51.

55 R.A. FARRARand ZHUYAOZHANG,,. Mater~ Sci. Leii., 12 (1993)f pp. 1606-1611.

Books on Welding fromThe Institute of Materials

B557 Metallurgical Modelling of Welding0ystein Grong

This book gives graduate students, engineers and researchers an in-depthinsight into the field of welding metallurgy, providing a broad overview of

fundamental principles.In recent years, significant progress has been made in the understanding ofthe chemical and physical processes which take place during welding. Thistext brings together all the basic components necessary to reach the goal offaster process developments, optimisation of process and properties and the

possibility of developing new and more weldable alloys.600pp ISBN 0 901716 37 5 £85

B533 Mathematical Modelling of Weld PhenomenaH. Cerjak and K. E. Easterling (eds)

'Technically, it is the first comprehensive publication on mathematicalmodelling and contains an impressive collection of papers on heat flow,

melt turbulence, solidification structures and physical metallurgy. Further,exposition of the underlying principles is very clear, so that it covers muchof the existing basic knowledge on welding. Several papers are definitive

and the book should become a standard reference in every welding library.'A. T. Price, Ironmaking and Steelmaking

384pp ISBN 0 90 1716 16 2 £65

B594 Mathematical Modelling of Weld Phenomena 2H. Cerjak (ed.), H. K. D. H. Bhadeshia (series ed.)

The second in the Institute's new Materials Modelling Series. Theproceedings of a conference held under the auspices of the InternationalInstitute of Welding Commissions IX and IXB and the Dept. of Materials

Science and Welding, Technical University of Graz.288pp ISBN 0 901716 63 4 £65

Documents

Atlas of continuous cooling transformation (CCT) diagrams applicable to low carbon low alloy weld Metals (matsci