The Effect of Aluminum in Shielded Metal
Arc C-Mn Steel Multipass Deposits
Hardness and toughness are most affected by varying levels
of aluminum in the weld metal
BY G. M. EVANS
ABSTRACT. The effect of varying the aluminum content of an E7018-type electrode on weld metal composition, microstructure and properties has been studied.
This investigation found that aluminum
modified the as-deposited and reheated
microstructure and changed the composition of the nonmetallic inclusions. The
weld metal hardness and tensile properties increased with increasing aluminum,
and optimum impact properties, for both
the as-welded and the stress-relieved condition, were exhibited at zero aluminum
and somewhat less favorably at an intermediate aluminum content of approximately 350 ppm.
Introduction
This investigation forms part of a joint
program, within Subcommission IIA of the
international Institute of Welding, to study
the factors affecting the microstructure
and properties of multipass shielded metal
arc welds. Previous work has examined
the process parameters (Ref. 1) and considered the relative effects of the main elements occurring in mild steel weld metal,
namely carbon (Refs. 2, 3), manganese
(Refs. 1-3), silicon (Ref. 4), sulfur (Ref. 5)
and phosphorus (Ref. 5). The influence of
weld metal aluminum content has now
been evaluated as one of the initial steps
in the process of understanding the role of
residual elements in multipass weldments.
Aluminum is introduced into SMA welds
either by dilution from the base plate or
from the coating and the core wire. Continuous cast wires, in particular, are a
possible source of aluminum and, since
the cost advantage and availability of
"rimmed" steel produced by the ingot
G. M. EVANS is with Welding Industries Oerlikon Buhrle Ltd., Zurich. Switzerland.
Paper presented at the 71st Annual AWS
Meeting, held April 22-27, 1990, In Anaheim,
Calif.
32-s | JANUARY 1991
route are being progressively eroded, it is
of practical importance to quantify the effect of the element.
Experimental Procedure
Electrodes
A balanced range of nine experimental
basic iron powder-type electrodes was
prepared by progressively increasing the
amount of aluminum powder in the coating, up to a maximum of 7%. The consumables were of the C type, according to
a previous designation (Refs. 1-4), and
yielded weld metals with a nominal composition of 0.08% C, 1.4% Mn and 0.35%
Si. The rimmed core wire employed was
4-mm (0.16-in.) diameter and the coating
factor (D/d) was 1.68.
Weld Preparation
The joint geometry was that specified in
ISO 2560, 1973. Welding was done in the
flat position and three beads per layer
were deposited (Ref. 1). The total number
of runs required to fill the individual joints
was 27. Direct current (electrode positive)
was employed, the amperage being 170
A, the arc voltage 2 1 V and the nominal
heat-input 1 k j / m m (25 kj/in.). The interpass temperature was standardized at
200°C (392°F).
KEY WORDS
Effect of Aluminum
E7018 Electrode
Aluminum in E7018
Inclusion Composition
Nonmetallic Inclusions
Al Effect on Impact
Multipass SMA Welds
Residual Elements
Microstructure Effects
IIW Subcommission IIA
Mechanical Testing
Two subsize all-weld-metal tensile specimens were machined and tested for each
of the different deposits. Also, approximately 35 Charpy V-notch specimens
were struck, so as to obtain a full transition
curve. The impact specimens were in the
as-welded condition, whereas the tensile
specimens were given a hydrogen removal treatment at 250°C (484°F) for 14
hours.
Metallography
Transverse sections were prepared, and
detailed examination was carried out on
the top beads and on the adjacent supercritically reheated zones, as described
previously (Refs. 1-4). Nonmetallic inclusions in six of the weldments were chemically analyzed using an SEM-based automatic image analyzer, and the mean threedimensional particle diameter was determined (Ref. 6).
Results
Chemical Composition
The chemical analyses of the nine allweld-metal deposits studied are given in
Table 1. Carbon was essentially constant,
but manganese and silicon tended to be
unbalanced for the last three weldments
of the series. As expected, increasing
amounts of aluminum were transferred
into the deposits, as shown in Fig. 1. Titanium was successfully balanced and, rather
fortunately, oxygen remained invariable.
On the other hand, residual and total
nitrogen contents decreased with increasing aluminum, as depicted in Fig. 2.
Metallographic Examination
General—Macro examination of the
weldments revealed no essential differences with regard to segregation or the
degree of recrystallization, which was approximately 70-80% at the Charpy V-
Table 1 - -Chemical Composition of Weld Deposits1*'
Code
Aluminum in
coating, %
0
1
2
3
4
5
6
6.5
7
P
—
Q
R
—
S
(a)
(b)
(c)
(d)
(e)
C
Mn
Si
0.069
0.073
0.078
0.080
0.080
0.076
0.078
0.076
0.079
1.36
1.39
1.39
1.41
1.42
1.36
1.31
1.30
1.32
0.30
0.33
0.32
0.33
0.37
0.37
0.44
0.51
0.57
S
P
A|(b)
TiC)
OM
0.007
0.007
0.007
0.006
0.006
0.005
0.005
0.005
0.004
0.009
0.008
0.009
0.009
0.009
0.009
0.008
0.008
0.008
<5
20
44
78
120
190
340
490
610
37
39
42
43
43
36
36
43
38
432
427
436
432
439
422
431
423
422
N(d)
N(e)
Total
Residual
67
66
66
61
54
54
52
50
48
33
n.d.
n.d.
34
n.d.
24
18
17
18
ppm
%
Nb, V, 8 < 5 p p m .
ICP-AES.
BALZERS
LECO;.
T W I . ref. 7.
notch location (Ref. 1). However, the average columnar grain width in the top
beads was observed to differ, firstly increasing with increasing aluminum, then
decreasing and finally increasing again, as
indicated in Fig. 3.
As-Deposited Weld Metal —lop beads
of six chosen deposits were optically examined and metallographic measurements
were made, following the current guidelines (Ref. 8) of IIW Subcommission IX I, to
quantify the major microstructural components, namely: primary ferrite (PF), ferrite with second phase (FS) and acicular
ferrite (AF).
The point count results obtained are
plotted in Fig. 4 and reveal a complex situation. Initially, aluminum induced a decrease in the volume fraction of acicular
ferrite before increasing the amount and
then subsequently decreasing it again. The
changes were compensated for by a
reverse trend in the volume fraction of
ferrite with second phase, the amount of
primary ferrite remaining relatively constant.
Photomicrographs of as-deposited columnar regions of welds containing 5, 78,
340 and 610 ppm Al - designated P, Q, R
fine-grained reheated regions became
more duplex in character, and increasing
difficulty in measurement, at the recommended (Ref. 9) magnification of 630X,
was encountered. The same problem has
been reported on adding major alloying
elements, such as M o (Ref. 10) and Cr
(Ref. 11), to the C-Mn system.
More detailed examination, using the
scanning electron microscope (SEM), revealed that the microphases associated
with the equiaxed ferrite grains were
martensite/austenite (M/A) and cementite films. Little change in microphase morphology could be detected with increasing aluminum, and the volume fraction increased only marginally from 8 up to
approximately 10%. The grain boundary
cementite films, however, were perceptibly thicker and possibly more continuous
at high aluminum contents, as seen on
comparison of the t w o micrographs
shown in Fig. 10.
and S, respectively —are shown at X100
magnification in Fig. 5. Of note, even at
this low magnification, is the coarse structure exhibited at the highest level of
aluminum investigated. Further detail, illustrating columnar regions, is shown in
Fig. 6. Ferrite with second phase is particularly evident in S, and coarsening of the
acicular ferrite laths and the associated
microphases is seen to have occurred.
Reheated Weld Metal—Examination of
the high-temperature regions directly
below the top beads revealed similar
changes to those encountered in the
as-deposited metal, as shown in Fig. 7. In
the extreme case (S), ferrite envelopes still
delineated the prior austenite grain boundaries, but ferrite with aligned second phase
had replaced approximately 50% of the
fine acicular structure within the grains.
Modifications were also observed in
the low-temperature reheated regions, as
seen in Fig. 8, on comparison of the t w o
extreme aluminum levels, P and S. Grain
size measurements (Ref. 9) are plotted in
Fig. 9 and indicate grain refinement up to
approximately 300 ppm Al and thereafter
a slight grain coarsening. At high aluminum contents, however, the so-called
1
i
1
1
Nonmetalic Inclusions
Six deposits were examined (Ref. 6) at
SINTEF (Norway) to determine the composition of the inclusions and the mean
i
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RESIDUAL
100 200 3 0 0 400 5 0 0 6 0 0
ALUMINIUM IN WELD. ppm.
700
Fig. 1 — Plot of aluminum in electrode coating
against aluminum in weld metal.
1
0
1
!
1
1
100 200 3 0 0 4 0 0 5 0 0 6 0 0
ALUMINIUM IN WELD. ppm.
1
700
100 2 0 0 300 4 0 0 5 0 0 600
ALUMINIUM IN WELD.ppm.
Fig. 2 —Plot of residual, free and total nitrogen
content against aluminum in weld metal.
700
Fig. 3 —Effect of aluminum on the average columnar grain width (top bead).
WELDING RESEARCH SUPPLEMENT 133-s
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Fig. 5 — Photomicrographs
100 200 300 400 500
ALUMINIUM IN WELD.ppm.
Fig. 4 - Effect of aluminum on the
ture of as-deposited weld metal.
of top beads (different aluminum
Al)
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34-s | JANUARY 1991
x
630
3 (610
oi top beads (different aluminum
Al)
contents).
three-dimensional particle diameter. The
analytical results are plotted in Fig. 11 and
show that M n O and Si02 were progressively replaced by AI2O3. The data are superimposed on the tertiary Al203-MnOSi02 diagram in Fig. 12. The Si to Mn
ratio in the deoxidation products was relatively constant and significantly higher
than that of stoichiometric Rhodonite
(MnO • Si02>. At the zero aluminum level,
some pure silica inclusions were identified,
but otherwise most particles contained
measurable amounts of both sulfur and
copper.
Histograms of inclusion size distributions, based in each case on measurement
of 500 particles, are presented in Fig. 13.
The arithmetic mean three-dimensional
diameter was virtually independent of the
weld metal aluminum content, varying at
the most between 0.32 and 0.38 (im. Also,
it was ascertained that the average aspect
ratio of the particles, determined as being
approximately 1.2, was essentially independent of the aluminum level.
Examination of replicated inclusions in
the scanning transmission electron microscope (STEM) revealed that high-aluminum-containing inclusions were rarely acting as nucleation sites for acicular ferrite
formation in as-deposited weld metal. Examples for the two extremes are shown in
Fig. 14. At low aluminum, the inclusion is
typically a nucleating M n O • Si02 particle
associated with surface compounds containing Mn, Cu, S and sporadically a high
local concentration of Ti. The high aluminum example in Fig. 14 is an inert A l 2 0 3
inclusion. Manganese, copper and sulfur
were found near the surface, but little
trace of titanium could be detected. Of
note, at high aluminum contents, was a
tendency for the inclusions to cluster and
even impinge in some cases.
Mechanical Properties
Hardness Testing — Average hardness
values obtained for the top beads are
plotted in Fig. 15. Apart from a slight initial
and final drop, a generally increasing trend
5*5 '
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x
P (-=5 A l )
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Fig. 7-- Photomicrographs of the high-temperature reheated regions (low- and high-aluminum contents).
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120
190
340
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610
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540
543
549
564
560
570
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Fig. 8-• Photomicrographs of the low-temperature reheated regions (low- and high-aluminum contents).
in hardness is depicted with increasing
aluminum.
Tensile Results — The tensile test data
are presented in Table 2. The yield and
tensile strengths are plotted against weld
metal aluminum content in Fig. 16 and
show a generally increasing but nonlinear
trend. The change, however, is slight and
possibly influenced by the imbalance in
silicon (Ref. 4).
Impact Results — Charpy V-transition
curves obtained for six of the nine weldments are drawn in Figs. 17 and 18 for the
as-welded and the stress-relieved condi-
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100 200 300 400 500 600
ALUMINIUM IN WELD. ppm.
I
700
Fig. 9 — Effect of aluminum on the grain intercept in the low-temperature reheated region.
Stress-Relieved (2 h/580°C)
El
N/ nm2
468
475
478
478
480
485
491
485
491
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Table 2— Mechanical Test Results
Aluminum
in Weld.
ppm
S (610 A l )
RA
TE
32.6
33.4
30.4
31.2
29.0
31.4
28.2
25.2
29.2
TR
El
N/mm2
%
80.7
80.7
78.9
80.7
78.9
79.8
78.9
78.9
77.0
393
387
398
391
397
403
409
417
443
RA
%
500
493
499
504
518
519
528
528
550
31.8
32.5
32.8
31.8
31.0
29.1
31.0
29.0
29.4
77.0
80.7
80.7
78.9
79.8
78.9
78.9
78.9
76.0
WELDING RESEARCH SUPPLEMENT 135-s
In order to study the role of aluminum
in isolation, an attempt was made in the
present investigation to balance the weld
metal composition. This was achieved by
progressively reducing the amount of
manganese and ferro-silicon in the coating, as aluminum was added. The deoxidation potential was maintained and weld
metal oxygen remained constant. The
amount of titanium in the welds was additionally balanced, and by a judicious
choice of raw material (Ref. 17), the background level of Nb, V and B was kept low
(<5 ppm). The total nitrogen content,
however, tended to decrease, due presumably to dilution by aluminum vapor in
the arc atmosphere. The residual nitrogen
also decreased, whereas, the free nitrogen remained essentially unchanged.
Thus, in accord with the work of Terashima and Hart (Ref. 18), it can be concluded that aluminum nitride formation
does not occur at the cooling rates inFig. 10— Microphases in the low-temperature reheated regions (low- and high-aluminum contents). volved.
SIO,
Cu
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0
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0.02
0.04
0.06
Aluminium In Weld Metal, wt%
MnO
20
40
wt% Al 2 0 3
60
80
AI2O3
•-
Fig. 11 — Effect of aluminum on weld metal inclusion composition.
Fig. 12 — Ternary system with superimposed
inclusion compositions.
tion, respectively. The test temperatures
corresponding to absorbed energies of
100 and 28 j (74 and 21 ft-lb) are plotted
in Fig. 19. It is seen that optimal toughness
was exhibited at the lowest aluminum
level and that stress relieving was generally beneficial; the lateral shift for 100 J
ranging between —8° and —15°C.
The temperatures corresponding to 100
J are reconsidered in Fig. 20 against the
ALO ratio. Three distinct domains are evident, increasing aluminum being first deleterious, then beneficial, as the ratio increased from 0.2 to approximately 0.8,
and finally deleterious again as the value
exceeded 0.8.
deposits is governed by nonmetallic inclusions and that the efficacy of these small
particles varies with size and composition.
Efficacious ferrite nucleants can be produced by achieving an appropriate balance of aluminum and oxygen in the
welds, and thus in the inclusions, or by introducing a sufficient level of Ti. An excess
of aluminum was considered detrimental,
even in the presence of a significant level
of Ti, and it was postulated that a dearth
of Al is not deleterious when sufficient Ti
is present. Harrison (Ref. 13) further reviewed the factors influencing the toughness of line pipe welds and concluded,
from the work of Thewlis (Ref. 14), that an
optimum ALO ratio of 0.84 is desirable,
i.e., corresponding to the stoichiometry of
galaxite (AI2O3 • MnO). Similarly, from the
data of Saggese, ef al. (Ref. 15), and of
Bonnet and Charpentier (Ref. 16), it was
proposed that the Ti:0 ratio be optimized
at 0.1.
Discussion
In reviewing the relevant literature,
which deals almost exclusively with submerged arc welding, Abson (Ref. 12) concluded that the microstructure of weld
36-s | JANUARY 1991
Metallographic examination of top
beads revealed that aluminum induced a
change in the average columnar grain
width, initial coarsening being followed by
refinement and subsequently by coarsening again above 200 ppm. According to
Kluken, et al. (Ref. 19), nonmetallic inclusions play a critical role in the development of the columnar grain structure by
acting as inert substrates for nucleation of
delta ferrite ahead of the advancing interface. The modifications to the prior austenite grain size were accompanied by
equivalent changes in the volume fraction
of ferrite with second phase, a minimum
being attained at 200 ppm Al. Complex
austenite grain size/transformation temperature characteristics have recently
been reported by Thewlis (Ref. 20) as due
largely to changes in inclusion composition. It was proposed that TiO/TiN and
galaxite are particularly active substrates
for increasing the propensity to intragranular ferrite formation. Several interrelated
effects are operative, and at this stage, it
can only be surmised that the TiO/TiN
present on the surface layers of manganese silicate particles was progressively
modified. Initially, acicular ferrite decreased as aluminum was added and the
formation of complex spinels is assumed,
as encountered on adding sulfur (Ref. 5).
At the stage at which the prior austenite
grain size decreased, it is concluded that
galaxite became an active component. Finally, with increasing AI2O3, transformation was modified, and increasing difficulty was encountered in promoting acicular ferrite. Of interest is the fact that the
change in average composition of the inclusions was not accompanied by a difference in size distribution.
The hardness of the top beads generally
increased with increasing aluminum, apart
from a slight initial and final drop. The
former could possibly be associated with
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inclusions.
Fig. 14 —STEM micrographs of replicated inclusions in low- and high-aluminum-containing
welds.
WELDING RESEARCH SUPPLEMENT | 37-s
P
240 f
a microstructural change but no explanation other than scattering can be put forward for the location of the latter. The
bulk tensile properties generally increased
monotonically with aluminum content,
with little evidence of microstructural dependence. The change was slight and
overshadowed to a certain extent by
variations in C, M n and Si. Postweld heat
treatment resulted in a reduction of the
tensile parameters, especially the yield
stress. The change was substantially
greater than that encountered previously
(Ref. 3), due to the absence of Nb and V
in the present instance.
Q
M-
600
5 Kg Load
180
300
100 200 300 4O0 500 600
ALUMINIUM IN WELD, p p m
700
Fig. 15 —Hardness of top bead plotted against
weld metal aluminum content.
0
• AS WELDED
STRESS RELIEVED
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ALUMINIUM IN WELD. ppm.
Fig. 76 — Yield and ultimate tensile strengths
plotted against weld metal aluminum content.
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STRESS RELIEVED
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Fig. 17—Charpy V-notch transition curves (as- Fig. 18 — Charpy V-notch transition curves
(stress-relieved condition).
welded condition).
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ALUMINIUM IN WELD. ppm.
700
Fig. 19 - Effect of aluminum on the Charpy Vnotch test temperature corresponding to 100
and 28 J.
38-s | JANUARY 1991
The lowest impact transition temperature was obtained for the aluminum free
deposit. On increasing aluminum, the
notch toughness depreciated rapidly but
then improved above 80 ppm Al. Subsequently, a second reversal occurred, and
the situation deteriorated again above an
aluminum content of about 350 ppm.
Three domains are thus indicated, the
first coinciding well with the microstructural change encountered in the as-deposited metal. The final reversal, however, corresponding to an ALO ratio of
0.8, was displaced to a higher concentration than that encountered for the maximum degree of acicularity. The Charpy Vnotch was located in the bulk of the deposit, which had undergone recrystallization, and evidently other factors, not
directly linked with acicular ferrite, were
operative at high aluminum content. The
reason is not understood but could be due
either to differences in the amount of ferrite with aligned second phase in the
high-temperature reheated regions or to
grain boundary carbide morphology in
the low-temperature reheated regions.
Of note is the fact that the grain size measurements in the latter region failed to distinguish any difference between 200 and
350 ppm Al. Apart from one instance,
postweld heat treatment improved notch
toughness, and the same trend was exhibited as for the as-welded condition.
The lateral shift induced by grain boundary carbide formation (Ref. 3) was substantial and enhanced by the absence of
vanadium in the present case.
For the aluminum-free electrode, less
than 5 ppm Al was found in the deposit.
On the basis of the impact data, it is predicted that dilution with aluminum-containing base metal, in a root situation, for
example, would have a deleterious effect.
Similarly, the evidence suggests that the
use of an aluminum-containing continuously cast core wire would also have a
negative influence on notch toughness.
The amount of aluminum introduced
would probably not exceed 80 ppm and,
0-5
10
in consequence, the situation could only
be alleviated by additionally introducing
(%AI)/(*0)
aluminum via the coating. Unfortunately,
Fig. 20 — Charpy V-notch test temperature corAl powder detrimentally affects the runresponding to 100 J plotted against ALO ratio.
ning characteristics of the electrodes, and
a c o m p r o m i s e is r e q u i r e d in practice.
T h e present study is limited t o t h e
e x t e n t that the results are specific t o a
w e l d metal o x y g e n c o n t e n t o f 4 3 0 p p m
a n d , c o n s e q u e n t l y , o t h e r degrees o f d e o x idation are currently being e x p l o r e d , so as
t o d e f i n e t h e A l - O system. In a d d i t i o n ,
since the titanium level in t h e present case
w a s standardized, f u r t h e r w o r k is envisaged t o characterize the Al-Ti system. By
this means, it is i n t e n d e d t o separate the
individual roles of a l u m i n u m a n d titanium
and clarify the influence of nonmetallic inclusion interfaces o n solidification substructure, prior austenite grain size a n d
acicular ferrite f o r m a t i o n . T h e basis f o r the
w o r k has already b e e n set, t h e M n - O syst e m having b e e n studied (Ref.17) in the
absence of b o t h a l u m i n u m and titanium.
Conclusions
For a balanced basic l o w - h y d r o g e n
e l e c t r o d e , of a specific slag base t y p e , the
f o l l o w i n g o c c u r r e d o n increasing f r o m
z e r o the a m o u n t of a l u m i n u m in t h e coating:
1) T h e m i c r o s t r u c t u r e o f as-deposited
w e l d metal w a s m o d i f i e d , w i t h t h e v o l u m e fraction of acicular ferrite initially d e creasing, t h e n increasing a n d finally d e creasing again.
2) T h e m e a n c o m p o s i t i o n o f t h e n o n metallic inclusions c h a n g e d , M n O and
Si02 being progressively r e p l a c e d b y A b
o3.
3) T h e hardness of as-deposited metal
t e n d e d , in t h e m a i n , t o increase.
4) T h e tensile p r o p e r t i e s of the d e p o s its marginally increased.
5) O p t i m u m n o t c h toughness characteristics w e r e exhibited at the z e r o alumin u m level.
6) F o l l o w i n g d e g r a d a t i o n f r o m z e r o alum i n u m , a small r e c o v e r y in toughness w a s
e n c o u n t e r e d at an a l u m i n u m c o n t e n t of
350 p p m .
Acknowledgments
T h e a u t h o r is i n d e b t e d t o M r . R. Zullig
f o r assistance w i t h the c o n v e n t i o n a l m e t allographic part o f t h e w o r k . Thanks are
also e x t e n d e d t o Dr. M . Es-Souni, G.K.S.S.,
f o r c o n d u c t i n g the e l e c t r o n m i c r o s c o p i c
studies, a n d t o D r . A. O . Kluken and Prof.
0. G r o n g , SINTEF ( N o r w a y ) f o r investigating the nonmetallic inclusions u n d e r c o n tract.
References
1. Evans, C. M. 1983. Factors affecting the
microstructure and properties of C-Mn allweld-metal deposits. Weld. Research Abroad,
WRC, 28 (1):1-69, also IIW Doc. 11-983-82.
2. Evans, C. M. 1983. The effect of carbon
on the microstructure and properties of C-Mn
all-weld-metal deposits. Welding Journal 62
(11):313-s to 320-s.
3. Evans, G. M. 1986. The effect of stressrelieving on the microstructure and properties
of C-Mn all-weld-metal deposits. Welding Journal 65 (12):326-s to 334-s.
4. Evans, C. M. 1986. The effect of silicon on
the microstructure and properties of C-Mn allweld-metal deposits. Metal Construction 18
(7):438R-444R.
5. Evans, C. M. 1986. The effect of sulfur
and phosphorus on the microstructure and
properties of C-Mn all-weld metal deposits.
Metal Construction 18 (10):631R-646R.
6. Kluken, A. O., Grong, 0 . , and Hjelen, J.
1988. SEM based automatic analysis of nonmetallic inclusions in steel weld metals. Mat. Sci.
Techn., 4:649-654.
7. Stevens, S. M. 1989. Derivation of a procedure for determining free nitrogen in ferritic
steels. Welding Institute Members Research
Report, 406.
8. Guidelines for classification of ferritic steel
weld metal microstructural constituents using
the light microscope. 1986. Weld, in the World,
(7/8)24:144-149;also IIW Doc. IX-1377-85.
9. Davey, T. C , and Widgery, D. |. 1976. A
technique for the characterization of weld
metal microstructures. IIW Doc. II-A-389-76.
10. Evans, C. M. 1988. The effect of molybdenum on the microstructure and properties of
C-Mn all-weld-metal deposits. Joining and Materials 1(5):239-246.
11. Evans, G. M. 1989. The effect of chromium on the microstructure and properties of
C-Mn all-weldmetal deposits. Welding and
Metal Fab. 57(7): 346-358.
12. Abson, D.). 1987. Small particles in weld
m e t a l s - a review. IIW Doc. IX 1-122-87.
13. Harrison, P. L. 1989. Factors influencing
the toughness of submerged arc welded line
pipe welds. The Welding Institute Bulletin, pp.
12-15 and 64-67.
14. Thewlis, G. 1986. The influence of pipe
plate and consumable chemistry on the composition, microstructure and toughness of weld
metal. Proc. Conf. Welding and Performance of
Pipelines. The Welding Institute, London, England, pp. 205-227.
15. Saggese, M. E., Bhatti, A. R., Hawkins,
D. N., and Whiteman,). A. 1983. Factors influencing inclusion chemistry and microstructure
in submerged arc welds. Proc. Conf. The Effects
of Residual, Impurity and Micro-Alloying Elements. The Welding Institute, London, England,
Paper 15.
16. Bonnet, C., and Charpentier, J.-P. 1983.
Effect of deoxidation residues in wire and of
some particular oxides in CS fused fluxes on the
microstructure of submerged-arc weld metals.
Ibid, Paper 8.
17. Abson, D. |., and Evans, G. M. 1989. A
study of the manganese-oxygen system in lowhydrogen M M A all-weld-metal deposits. Second International Conf. Trends in Welding Research, Gatlinburg, Tenn.
18. Terashima, H., and Hart, P. H. M. 1983.
Effect of flux TiC>2 and wire Ti content on tolerance to high Al content of submerged arc
welds made with basic fluxes. Proc. Conf. The
Effects of Residual, Impurity and Microalloying
Elements, The Welding Institute, London, England, Paper 27.
19. Kluken, A. CV, Grong, 0 . , and R^rvik, G.
Solidification microstructures and phase transformations in Al-Ti-Si-Mn deoxidized steel weld
metals. Report N ° . STF 34 A 89110, SINTEF,
Trondheim, Norway.
20. Thewlis, G. Transformation kinetics of
weld metal. British Steel technical report, to be
published.
WRC Bulletin 353
May 1990
Position Paper on Nuclear Plant Pipe Supports
T h i s p o s i t i o n p a p e r r e c o m m e n d s d e s i g n m e t h o d s w h i c h r e p r e s e n t t h e c o l l e c t i v e " b e s t m e t h o d s " of t h e
i n d u s t r y . T h e s e e n h a n c e d design m e t h o d s are d e v e l o p e d by r e v i e w i n g t h e issues t h a t h a v e a d d e d t o t h e
c o m p l e x i t y of d e s i g n a n d f a b r i c a t i o n of p i p i n g s y s t e m s .
P u b l i c a t i o n o f t h i s r e p o r t w a s s p o n s o r e d b y t h e T a s k G r o u p o n N u c l e a r P l a n t P i p e S u p p o r t s of t h e
T e c h n i c a l C o m m i t t e e o n P i p i n g S y s t e m s of t h e P r e s s u r e V e s s e l R e s e a r c h C o u n c i l of t h e W e l d i n g R e s e a r c h
C o u n c i l . T h e p r i c e of W R C B u l l e t i n 3 5 3 is $ 2 5 . 0 0 p e r c o p y , p l u s $ 5 . 0 0 f o r U.S., o r $ 1 0 . 0 0 f o r o v e r s e a s ,
p o s t a g e a n d h a n d l i n g . O r d e r s s h o u l d b e s e n t w i t h p a y m e n t t o t h e W e l d i n g R e s e a r c h C o u n c i l , 3 4 5 E. 4 7 t h
St., R o o m 1 3 0 1 , New York, NY 1 0 0 1 7 .
W E L D I N G RESEARCH S U P P L E M E N T | 3 9 - s
WRC Bulletin 343
May 1989
Destructive Examination of PVRC Weld Specimens 202, 203 and 251J
This Bulletin contains three reports:
( 1 ) Destructive Examination of PVRC Specimen 202 Weld Flaws by JPVRC
By Y. Saiga
( 2 ) Destructive Examination of PVRC Nozzle Weld Specimen 203 Weld Flaws by JPVRC
By Y. Saiga
( 3 ) Destructive Examination of PVRC Specimen 251J Weld Flaws
By S. Yukawa
The sectioning and examination of Specimens 202 and 203 were sponsored by the Nondestructive
Examination Committee of the Japan Pressure Vessel Research Council. The destructive examination of
Specimen 251J was performed at the General Electric Company in Schenectady, N.Y., under the
sponsorship of the Subcommittee on Nondestructive Examination of Pressure Components of the
Pressure Vessel Research C o m m i t t e e of the Welding Research Council. The price of WRC Bulletin 343 is
$24.00 per copy, plus $5.00 for U.S., or $8.00 for overseas, postage and handling. Orders should be sent
with payment to the Welding Research Council, Room 1 3 0 1 , 345 E. 4 7 t h St., New York, NY 10017.
WRC Bulletin 354
June 1990
The two papers contained in this bulletin provide definitive information concerning the elevated t e m perature rupture behavior of 2V4Cr-lMo weld metals.
( 1 ) Failure Analysis of a Service-Exposed Hot Reheat Steam Line in a Utility Steam
Plant
By C. D. Lundin, K. K. Khan, D. Yang, S. Hilton and W. Zielke
( 2 ) The Influence of Flux Composition of the Elevated Temperature Properties of Cr-Mo
Submerged Arc Weldments
By J. F. Henry, F. V. Ellis and C. D. Lundin
The first paper gives a detailed metallurgical failure analysis of cracking in a longitudinally welded hot
reheat pipe with 184,000 hours of operation at 1050°F. The second paper defines the role of the welding
flux in submerged arc welding of 2V4Cr-lMo steel.
Publication of this report was sponsored by the Steering and Technical Committees on Piping Systems
of the Pressure Vessel Research Council of the Welding Research Council. The price of WRC Bulletin 3 5 4
is $50.00 per copy, plus $5.00 for U.S. and $10.00 for overseas postage and handling. Orders should be
sent with payment to the Welding Research Council, 345 E. 4 7 t h St., Room 1 3 0 1 , New York, NY 10017.
40-s | JANUARY 1991