RMS Titanic: A Metallurgical Problem
H.P. Leighly, B.L. Bramfitt and S.J. Lawrence, RMS Titanic: A Metallurgical
Practical Failure Analysis, Vol 1 (No. 2), Apr 2001,
On 14 April 1912, at 11:40 p.m., Greenland Time, the Royal Mail Ship Titanic on its maiden voyage was proceeding westward at 21.5 knots (40 km/h) when the lookouts on the foremast sighted a massive iceberg estimated to have weighed between 150,000 to 300,000 tons at a distance of 500 m ahead. Immediately, the ship's engines were reversed and the ship was turned to port (left) in an attempt to avoid the iceberg. In about 40 seconds, the ship struck the iceberg below the waterline on its starboard (right) side near the bow. The iceberg raked the hull of the ship for 100 m, destroying the integrity of the six forward watertight compartments. Within 2 h 40 min the RMS Titanic sank. Metallurgical examination and chemical analysis of the steel taken from the Titanic revealed important clues that allow an understanding of the severity of the damage inflicted on the hull. Although the steel was probably as good as was available at the time the ship was constructed, it was very inferior when compared with modern steel. The notch toughness showed a very low value (4 joules) for the steel at the water temperature (-2 deg C) in the North Atlantic at the time of the accident.
Nonmetallic inclusions; Passenger ships; Ship plate; Steel making
(Nonresulfurized carbon steel)
One evening in early 1907, Lord William James Pirrie, managing
director and controlling chairman, Harland and Wolff, Shipbuilders, Belfast,
Northern Ireland, entertained at dinner J. Bruce Ismay, chairman, Oceanic
Steam Navigation Company. This latter company was better known as the White
Star Line, named after the company pennant, a white star on a red field. The
White Star Line was owned by the International Mercantile Marine Company,
which was controlled by J.P. Morgan. After their meal, the two men planned
the future of the White Star Line.
At that time, the chief competitor to the White Star Line was the Cunard
Steamship Company, which had the two largest and fastest passenger ships in
the world, the RMS Lusitania and the RMS Mauretania, each having a gross tonnage
of 31,000 tons with a maximum speed of 26 knots (50 km/h). It was decided
that the White Star Line should establish a three-ship weekly steamship service
for passengers and mail between Southampton, England, and New York.
Harland and Wolff agreed to build three ships for the White Star Line,
each having a gross tonnage of 46,000 tons; the RMS Olympic, the RMS Titanic,
and the RMS Gigantic. (The name of the third ship was changed to the RMS Britannic
after the RMS Titanic tragedy.) These ships were to be built on a cost-plus
The White Star Line did not intend to compete in speed with the RMS
Lusitania and the RMS Mauretania (23 knots vs. 26 knots)(45 km/h vs. 50 km/h),
but rather to have more elegant accommodations and facilities than the Cunard
ships. In order to build such large ships, Harland and Wolff would have to
rebuild their shipyard replacing three smaller ways with two larger ones and
install new gantry cranes having greater load carrying capacity.
The keel of the RMS Olympic was laid on 16 December 1908, with the ship
being launched on 20 October 1910. The keel for the RMS Titanic was laid on
31 March 1909, followed by its launching on 31 May 1911. The RMS Titanic was
fitted out and ready for sea trials in early April 1912. There had been a
delay in the completion of the RMS Titanic because the RMS Olympic, on its
fifth voyage, and the British cruiser HMS Hawke collided in the Solent off
Southampton harbor on 20 September 1911.
The RMS Olympic was damaged on the starboard side 25 m forward of the stern.
The main damage was a gaping hole through the hull plates. After emergency
repairs were made in Southampton, it proceeded to Belfast for permanent repairs
at the shipyard of Harland and Wolff. Shipyard workers normally assigned to
work on the RMS Titanic were diverted to the RMS Olympic in order to return
it to service with as little delay as possible.
After two days of sea trials in the Irish Sea, the RMS Titanic tied
up at Ocean Dock in Southampton on 4 April 1912. The days before the scheduled
departure day, 10 April, were used to allow the workmen from the shipyard
to complete the outfitting of the ship, to permit the loading of provisions
on board for the voyage, to secure an adequate supply of coal because of a
miners strike, and to conclude the hiring of the hotel staff and the ship's
Shortly before noon on Wednesday, 10 April, the lines holding the RMS
Titanic to Ocean Dock were cast off and the RMS Titanic started down the Southampton
Water into the Solent, then into the English Channel. As the RMS Titanic passed
a neighboring dock where the SS New York was moored, a surge of water from
the RMS Titanic caused the SS New York to break its cables so that it drifted
toward the RMS Titanic. Skilled seamanship and the intervention by tug boats
prevented the ships from making contact with each other.
Cherbourg was the first port of call. The RMS Titanic arrived in the
port during the evening of the first day. Because the RMS Titanic was too
long for the dock, the passengers and mail were transferred from the dock
to the ship by the two White Star Line tenders, the SS Nomadic and the SS
Traffic. Many of the first class passengers came on board at Cherbourg after
having spent the winter in the South of France, on the Greek Isles, or in
The next morning, the RMS Titanic called at Queenstown (now Cobh), Ireland,
where the two tenders, the SS America and the SS Ireland, brought aboard about
130 passengers, mostly immigrants in steerage class, and 1400 sacks of mail,
much of which had been brought by train from London across southern England
and by boat across the Irish Sea the night before.
After leaving Queenstown, the Titanic headed west on a great circle
route toward “the corner,” which is located in the Grand Banks
of Newfoundland. At the corner, the direction would have been changed to a
straight course line toward Sandy Hook, which is located 25 km south of Manhattan
Island, New York. The Irish coast was left behind at dusk on Thursday, 11
The next morning, Friday, 12 April, the weather was sunny but cold.
Shortly after noon the French liner, SS La Touraine, sent advice by radio
of ice in the shipping lanes. This was almost 60 hours before the RMS Titanic
collided with the iceberg. In April, ice in the shipping lanes was not unusual;
however, during the spring of 1912, the amount of ice in the North Atlantic
was unusually large.
As the RMS Titanic continued westward on its course, more frequent and
more urgent radio messages were received repeating the warning of ice ahead
in the western North Atlantic. Twice Captain Edward Smith of the RMS Titanic
ordered the ship to a more southerly course but he failed to reduce the speed.
After the sinking of the RMS Titanic, it was determined on the basis of several
reports that a very large icefield about 120 km long stretched on a northeast-southwest
axis across the shipping lanes. It was estimated to be about 20 km wide.
It was a moonless night on 14 April with no wind so the sea was dead
calm. At 11:40 p.m., Greenland time, the lookouts in the crow's nest on the
foremast spotted a huge iceberg, estimated to have weighed between 150,000
and 300,000 tons, about 500 m ahead. The bridge was alerted. The officer of
the watch, First Officer William Murdoch, ordered the engines to be reversed
and the ship be turned hard to port. Within 40 seconds, the RMS Titanic collided
with the iceberg, the point of impact being on the starboard side, just behind
the bow, about 3 m above the keel and 8 m below the water line. The iceberg
raked the hull of the Titanic for 100 m, cracking hull plates and popping
rivets, thus destroying the integrity of the first six of 16 watertight compartments
formed by the transverse bulkheads. Captain Smith and Thomas Andrews, a managing
director and chief designer for Harland and Wolff, together surveyed the ship.
Their findings revealed that the ship could not survive long because it had
been fatally damaged.
It was originally assumed that the collision developed a continuous
crack 100 m long in the hull; however, Edward Wilding,
a design engineer for Harland and Wolff, calculated on the basis of the rate
of flooding reported by survivors that openings in the hull totaling 1.115
had caused the RMS Titanic to sink. Recent computer calculations
by Hackett and Bedford
same survivors' information, but allocating the damage to the first six individual
compartments, is given in
. Their calculated total area of openings in the hull is 1.171 m2
Table 1 Summary of damaged areas in the hull by compartments
Computer Calculations (m2)
Cargo Hold 1
Cargo Hold 2
Cargo Hold 3
Boiler Room 6
Boiler Room 5
The compartments are listed in
order from the bow toward the stern.
Reproduced with permission of the
Journal of Metals.
gave the order to abandon ship. It was difficult to persuade many of the passengers
that the RMS Titanic was really sinking. In keeping with the British Board
of Trade regulations of 1894, the RMS Titanic carried 16 lifeboats, the minimum
allowable number. In addition, it carried four Engelhardt collapsible lifeboats.
The total capacity of all these lifeboats was about 1100 persons, approximately
half the number of people on board the ship. Very few of the lifeboats were
loaded to their designed capacity before being lowered away, and only 706
persons were saved.
The fraction of those on board who were saved was greatest among the
first class passengers, next were the second class passengers, and last were
the steerage passengers, the crew, and the hotel staff. Because the voyage
took place early in the sailing season, the RMS Titanic was not filled to
capacity. It could have taken another 1000 passengers.
At 2:20 a.m., 15 April, the RMS Titanic sank below the surface of the
North Atlantic. It went bow down at about a 350 angle. The stern section broke
from the bow and drifted away to sink separately. The bow, being full of water,
sank very quickly, burying itself 19 m into the mud on the bottom of the ocean.
The stern sank more slowly. Both major pieces now sit in 3,700 m of water
about 600 m apart with a debris field between them. Both sections are in the
The Manufacturing of Steel Plate
To determine the possible contribution the hull steel made to the demise
of the RMS Titanic, the following factors will be considered: the chemical
composition, the microstructure, and the mechanical properties, mainly the
notch toughness as determined by the Charpy Impact Test.
The steelmaking process can have an important effect on these factors.
Steelmaking between the time of the construction of the RMS Titanic, 1909
to 1911, and current steelmaking practice are vastly different. It has been
suggested that Harland and Wolff used less expensive and inferior steel; however,
there was no incentive to use such steel — as pointed out previously,
they had a cost-plus fixed-fee contract with the White Star Line to build
the three ships of the RMS Olympic class.
Ship Plate Manufactured for the RMS Titanic
It is believed that the main source of the steel plate used for the
construction of the RMS Titanic was the steelworks of David Colville and Company
located in the Borough of Dalzell in Motherwell, Scotland.
Evidence to support the supposition that the steel used in the Titanic was
provided by David Colville and Company is a piece of channel beam with “Dalzell”
embossed on it that was retrieved during the 1996 expedition. An earlier expedition
recovered another small piece
of the hull of the RMS Titanic. The hull plate used in this study was recovered
in August 1996 from the debris field located between the bow and stern sections
on the bottom of the ocean.
According to Davis
of the steel produced in Britain in 1910 was made in acid-lined open hearth
installed a 50
ton acid-lined open hearth furnace in 1906. An acid-lined open hearth furnace
utilized acid refractories such as silica, fireclay, and ganister as the lining
for the furnace. An acid slag practice was employed. Because of the use of
acid lining in the open hearth furnace and the acid slag practice, phosphorus
and sulfur could not be removed during the steelmaking process. Low sulfur
steel could be produced if a low sulfur pig iron was used, such as that smelted
from low sulfur iron ore obtained from Sweden. This was a common source of
iron ore used in Britain in the late 19th and early 20th century.
However, Swedish iron ore contained about 15% titanium dioxide, which requires
more fuel and a higher blast furnace operating temperature because it is more
difficult to reduce the ore to iron.
Colville continued to use cold pig iron and steel scrap to make steel
in an acid-lined open hearth furnace until 1919.
From the composition of the steel used to construct the RMS Titanic given
, namely the high
sulfur and high phosphorus content, it is apparent that it was made in an
acid-lined furnace. The low nitrogen content precludes the possible use of
a Bessemer converter in making this steel.
Table 2 Chemical analysis of the RMS Titanic and modern steel
The open hearth furnace was tapped into a ladle after
the steel was melted and refined. The low silicon and high oxygen content
indicates that there may have been only limited deoxidation as the tapping
occurred. The steel was teemed into ingot molds and allowed to solidify. The
molds were stripped and the ingots were reheated in a soaking pit. They were
rolled into 2.54 cm thick plates and allowed to air cool.
Modern Ship Plate Manufacturing Practice
To provide a comparison between the properties of the steel used in
the RMS Titanic and modern steel, 1.25 cm hot-rolled plate manufactured by
the Bethlehem-Lukens Plate Division of the Bethlehem Steel Corporation was
obtained. The steel had been melted using steel scrap in an electric furnace.
After melting and refining, the molten steel was tapped into a ladle. Through
a porous plug in the bottom of the ladle, argon gas was bubbled through the
molten steel to assist in mixing the alloy additions, such as carbon, manganese,
and silicon, and to partially purge dissolved gases, such as hydrogen and
oxygen. The silicon was added to provide deoxidation of the steel. Phosphorus
and sulfur were reduced by the use of a special molten slag of basic composition
placed on the top of the molten steel in the ladle. The gas removal was completed
by placing the ladle in a chamber that can be evacuated that substantially
lowered the oxygen and hydrogen content in the steel.
After these procedures were performed, the steel was continuously cast
to produce a solid slab, which was cut to the desired lengths. During the
casting, care was taken to shield the molten steel from contact with the atmosphere.
A tundish located directly above the continuous casting mold trapped inclusions
and slag that floated in the molten stream of steel. The slabs were heated
to the desired rolling temperature to produce a plate 1.25 cm thick.
Two steel plates provided the material for the following experimental
A piece of the hull plate
of the RMS Titanic 1.60 cm thick was recovered in August 1996 from the debris
field at the bottom of the North Atlantic Ocean between the bow and stern
sections of the ship. Bringham and Lafreniere
had calculated that the hull plate retrieved in 1991 from the RMS Titanic
had been originally 2.54 cm thick prior to the sinking and that salt water
corrosion had reduced its thickness to 1.60 cm during the intervening years
between 1912 and 1996.
A plate 1.25 cm thick was produced in December 1998 at
the Bethlehem-Lukens Plate Division of Bethlehem Steel Corporation according
to the American Bureau of Shipping (ABS) grade A and the American Society
for Testing and Materials (ASTM) A 131 grade A specifications.
Tensile tests were conducted according to the ASTM E 8 standard test.
Duplicate specimens were prepared from both plates in the longitudinal direction.
Notch Toughness Tests
Standard V-notch Charpy test specimens were machined from the central
thickness for both plates in the rolling direction and in the transverse direction
according to ASTM E 23. The Charpy test was developed during the early 1900s.
Although the test had been developed before
the construction of the RMS Titanic, it had not been standardized. The ASTM
established their first Provisional Standard for the Charpy Impact Test in
Light and Scanning Electron Microscopy
Optical metallographic examination of the microstructure was conducted
to determine the volume percentage of pearlite, acicular ferrite, the grain
size, and the volume percentage of inclusions.
Scanning electron microscopy (SEM) was used to examine the fracture
surfaces of the Charpy specimens tested at various temperatures. With this
instrument, one can determine the mode of fracture as a function of test temperature,
i.e. to identify fracture in the upper and lower shelves and in the transition
regions of the absorbed energy vs. temperature curve. Energy dispersion spectroscopy
(EDS) was used to obtain chemical analysis of the nonmetallic inclusions lying
on the fracture surface. For more detailed chemical analysis of selected inclusions,
electron probe microanalysis (EPMA) using wavelength dispersion spectroscopy
(WDS) was employed.
Results and Discussion
The chemical composition of the hull plate recovered from the wreck
site of the RMS Titanic in 1996, as well as the composition of the modern
steel manufactured in 1998, are given in
. Basically the RMS Titanic plate is a plain carbon steel (0.21%
C) with higher than normal sulfur and phosphorus content. The Mn:S ratio for
the steel recovered in 1996 is 7:1. The modern steel is lower in carbon, oxygen,
sulfur, and phosphorus, all elements that are capable of reducing the notch
toughness of steel, and has a very respectable Mn:S ratio, 39:1. The RMS Titanic
steel would not have met ASTM or ABS chemistry requirements due to the excesses
of sulfur and phosphorus and deficiency in manganese.
As previously pointed out, the first ASTM Provisional Standard for Charpy
Impact Testing was established in 1933. Before that time, the only mechanical
properties for evaluating steel were the measurement of the yield strength,
the ultimate tensile strength, and the percent elongation on a 200 mm gage
length. For the steel to be used in the RMS Titanic, Harland and Wolff required
a design tensile strength of 34 to 45 ksi (234 to 310 MPa).
The tensile strength for the steel recovered in 1996 would have met their
requirement, as given in
. The modern steel plate also would have met the requirements of ASTM
Table 3 Tensile properties of the RMS Titanic and modern plates
193 (28 ksi)
417 (61 ksi)
338 (49 ksi)
441 (64 ksi)
The Charpy impact test results for specimens oriented in the longitudinal
and transverse directions for both the RMS Titanic steel and the modern hull
plate are plotted in
Not surprisingly the modern steel shows very
superior results. As a point of reference, it should be noted that the sea
water temperature at the time of the collision was -2 °C (29 °F).
The impact energy for the RMS Titanic steel at this temperature was 4 joules
(3 ft-lbs.) in both the longitudinal and the transverse directions. The ductile-brittle
transition temperature for the impact energy vs. temperature curve for specimens
taken from the RMS Titanic and oriented in the longitudinal direction was
30 °C. Those specimens oriented in the transverse direction had a transition
temperature of 42 °C.
Fig. 1 Longitudinal and transverse toughness of the 1996 RMS Titanic plate
compared with that of modern steel plate. Reproduced with permission of the
Iron & Steelmaker.
For the modern steel, the impact energy at -2 °C for the longitudinal
direction is 325 joules (240 ft-lbs.) and in the transverse direction the
impact energy is 100 joules (73 ft-lbs.). The ductile-brittle transition temperature
for the modern steel is -42 °C in both the longitudinal and transverse
The low notch toughness of the RMS Titanic steel of 4 joules (3 ft-lbs.)
at the temperature of the sea water (-2 °C) at the time of the collision
with the iceberg means that the steel would have been prone to brittle fracture.
Certainly brittle fracture of the steel hull plate contributed to the sinking
of the ship. The low manganese: sulfur ratio of 7:1 for the 1996 RMS Titanic
steel will allow the formation of iron sulfide or mixed iron-manganese sulfides
in preference to the formation of manganese sulfides. Iron sulfides tend to
be less plastic and more brittle than manganese sulfides. In order to have
only manganese sulfide present, the Mn:S ratio must be at least 20:1. The
modern steel used in this study has a Mn:S ratio of 39:1, hence yielding a
high notch toughness and the low ductile-brittle transition temperature.
It has been suggested that the sinking of the RMS Titanic was due exclusively
to the fracture of the rivets holding the hull plates together. The rivets
were made from wrought iron. This implies that fracture of the plates would
not have occurred as the iceberg raked the hull for 100 m. There were examples
of fracture with no ductile behavior observed on the edges of the plates recovered
during the 1996 expedition. Because the bow of the ship had plunged so deeply
into the mud at the bottom of the ocean (19 m), it will never be possible
to examine the nature and extent of the damage to the hull caused by the collision
with the iceberg.
The RMS Titanic plate from the 1996 expedition was prepared metallographically
to reveal the microstructure on the longitudinal and transverse directions,
as shown in
. The longitudinal
section shows pearlite and acicular ferrite. Because the direction of rolling
is parallel to the horizontal orientation of
, one observes banding of the pearlite colonies, and elongation
of the sulfide particles and silicate particles. The microstructure is fairly
typical of a 0.21% C steel. The percentage of pearlite is about 15% of the
microstructure. The acicular ferrite, about 5%, is the result of air cooling
of a steel having a large austenite grain size through the Ac3
temperature. The average grain size is 22.7 µm (ASTM 7.6). The transverse
section shows very little or no banding.
Fig. 2 The general microstructure of the (a) longitudinal and (b) transverse
planes of the RMS Titanic plate. (4% picral + 2% nital etch — 100×)
The microstructure of the modern steel plate is shown in
, both longitudinal and transverse sections. There
is no evidence of banding in either of the sections. For comparison, the same
magnifications are used in
. The microstructure
consists of ferrite and a small amount of pearlite, 8.5%, which is expected
because the carbon content is 0.09% in this steel. The grain size of the modern
steel is 20 µm (ASTM 7.9), somewhat smaller than the RMS Titanic steel.
Fig. 3 The general microstructure of the (a) longitudinal and (b) transverse
planes of the modern steel plate. (4% picral + 2% nital etch — 100×)
Analysis of the Non-metallic Inclusions
Optical microscopic examination of a well polished but unetched RMS
Titanic steel specimen revealed the non-metallic inclusions.
shows a typical worst field view (ASTM E 45)
of inclusions at 500times;, for the transverse plane. The dark gray inclusions
are silicates, whereas the light gray inclusions are sulfides. The elongated
and rounded particles of a large silicate and several sulfides are shown in
. The composition of the sulfide
particles determines its plasticity. Manganese sulfide particles are more
plastic than iron sulfides. The presence of iron in the manganese sulfide
reduces the plasticity of the particles.
Fig. 4 Typical worst yield view of inclusions at magnification of the RMS
Titanic steel plate in the transverse plane. (Unetched — 500×)
Fig. 5 View of a large silicate inclusion (dark gray) and smaller sulfides
(light gray) of the RMS Titanic plate in the tranverse plane. (Unetched —
100×. Reproduced with permission of the Iron & Steelmaker.
Because the RMS Titanic steel has a Mn:S ratio of 7:1, the MnS particles
will have a varying amount of iron replacing manganese. The silicate particles
(slag) are the result of their entrapment in the molten steel during teeming
into an ingot mold. By modern standards, the RMS Titanic steel is “dirty
steel.” It would not be acceptable by current standards. The RMS Titanic
steel (1996) has 0.396 vol.% sulfides and 0.133 vol.% silicates, as compared
with modern steel having 0.021 vol.% sulfides and 0.014 vol.% oxides and mixed
oxides and sulfides. From these data, it is apparent that the modern steel
is much cleaner than the RMS Titanic steel.
The characteristic X-rays emitted by the large silicate particle shown
are mapped in order
to identify the elements present. The resulting images are shown in
. The dominant and most uniformly
distributed element present is silicon, which is to be expected. Manganese
is nearly uniformly distributed, while the oxygen and silicon have a similar
density. This indicates that they co-exist as manganese silicate present in
copious amounts in the slag inclusion. The sulfur is confined to small regions
on the slag inclusion, which appear as “droplets” on the slag
particle shown in
silicon and oxygen have parallel concentrations while the sulfur concentration
is complementary to the silicon and oxygen concentration, i.e. where there
is a high concentration of silicon and oxygen, there is little or no sulfur
and vice versa. The small amount of titanium in the slag offers confirmation
to the idea suggested above that titanium bearing low sulfur iron ore from
Sweden was probably used to make the RMS Titanic steel in order to minimize
the sulfur in the steel produced in an acid open hearth furnace.
Fig. 6 X-ray maps showing the elements contained in the large silicate inclusion
Fig. 5. The maps are of
the same field shown in the BEI of
Fig. 7. Reproduced with permission of the Iron & Steelmaker.
Fig. 7 The back scattered image (BEI) of the large silicate particle in
Fig. 5. The arrows, 1, 2, and 3,
point to constituents analyzed by WDS. Reproduced with permission of the Iron
is a back scattered
electron image (BEI) of the slag particle shown in
. (Note that
images of the slag particle.) The arrows 1, 2, and 3 point to constituents
analyzed by wavelength dispersive spectroscopy (WDS). The dark appearing matrix
(arrow 1) is basically manganese silicate with a small amount of titanium
and no iron. The titanium is dissolved in the manganese silicate. Arrow 2
points to a dark gray particle that appears to be a mixture of manganese silicate,
MnS, FeS, and titanium. The presence of sulfide in the silicate slag suggests
that the sulfide, at high temperatures, is soluble in the slag but it becomes
immiscible at lower temperatures. The rounded particles, arrow 3, are essentially
MnS containing a small concentration of iron. This would be the product of
the rejection of the sulfide from the silicate caused by declining temperatures.
The Fracture Surfaces
SEM photomicrographs were taken of the fracture surfaces of several
broken Charpy specimens made from the plate from the RMS Titanic recovered
in 1996. Those in
from longitudinal Charpy specimens fractured at temperatures on the upper
and lower shelves, respectively. Those in
are similar specimens in the transverse direction. The specimen
broken in the upper shelf temperature range shows ductile fracture with inclusions
in the voids created during fracture. The Charpy specimens broken in the temperature
range of the lower shelf show cleavage fracture typical of low temperature
failure of steel.
Fig. 8 SEM micrographs showing fracture surfaces of longitudinal Charpy
specimens from the RMS Titanic plate tested at (a) 120 °C and (b) -32
°C. Reproduced with permission of the Iron & Steelmaker.
Fig. 9 SEM micrograph showing fracture surfaces of transverse Charpy specimens
from the RMS Titanic plate tested at (c) 148 °C and (d) -34 °C.
Reproduced with permission of the Iron & Steelmaker.
is the fracture
surface of a transverse Charpy specimen. The inclusion labeled B protrudes
from the surface. The EDS spectrum for particle A is substantially MnS with
a smaller amount of FeS while particle B is a nearly equal mixture of Fe and
Mn sulfide. This means that the A particle is more plastic than particle B.
This could account for the protrusion of particle B in that being less plastic,
it could have fractured as the specimen fractured.
Fig. 10 The SEM micrograph shows sulfide inclusions A and B in the fracture
surface of the transverse Charpy specimen from the RMS Titanic plate tested
at -34 °C. Reproduced with permission of the Iron & Steelmaker.
It is quite apparent from the test results and the metallography that
the steel obtained in 1996 from the site of the RMS Titanic was inferior in
mechanical properties to steel commercially available today. A significant
factor is that the last eight decades have shown a marked improvement in steelmaking.
The slag content of the RMS Titanic steel is absent in the modern steel
and the volume fraction of both sulfides and silicates is greater than in
the modern steel. The lack of cleanliness of the steel had a deleterious effect
on the mechanical properties, particularly the notch toughness as demonstrated
by Charpy Impact Tests.
These factors were contributing causes of the rapid sinking of the Titanic.
Omitted in this study have been design faults and poor seamanship, which were
basic to the loss of the RMS Titanic.
The authors wish to thank
Mr. George Tullock, RMS Titanic, Inc., for providing the steel for this study.
They wish to thank Dale Brown and his associates of Laclede Steel Company
for the chemical analysis of the steel plates from the RMS Titanic recovered
in August 1996. They wish to thank the machine shop crews of the School of
Mines and Metallurgy, University of Missouri-Rolla, and the Bethlehem-Lukens
Plate Division for preparing the RMS Titanic and the modern plate steel Charpy
specimens, respectively. Thanks goes to M. Roberson, UMR, for his special
knowledge of the Titanic and its fate. Acknowledgment also goes to Leonard
Salvage for conducting the microprobe analysis. Special acknowledgment goes
to Gavin Thomson, British Steel, plc, for providing historic information on
David Colville and Company.
Bookman Publishing Co., Baltimore,
MD, 1987, p. 32.
Avon Books, New York, 1988, p. 124.
R.B. Ballard with Rick Archbold:
The Discovery of the Titanic,
Warner Books, New York, 1987.
C. Hackett and J.G. Bedford:
The Sinking of the Titanic Investigated by Modern Techniques,
Northern Ireland Branch of the Institute of Marine Engineers and the Royal
Institution of Naval Architects, 26 March 1996.
A Technical Survey of the
Colville Group of Companies,
A. McLeod and D. Cleal, ed., Iron &
Coal Trades Review, London, England, 1957, pp. 6–7, 34–47, 48–55,
R.J. Bringham and Y.A. Lafreniere:
Report 92–32(TR), Materials Technology Laboratories,
CANMET, Ottawa, Canada, 1992.
J. Hist. Met.
1995, vol. 29(1), pp. 34–45.
1892–1895, vol. XXI, pp. 832–67.
and Properties of Iron and Steel,
Hill Publishing Co., New York,
NY, 1907, p. 42.
Report on Impact
Tests of Metals,
Proceedings, International Association for Testing
Materials, Vienna, Austria, vol. 1(5), May 1908 – Feb 1910.
M. Moss and J.R. Hume:
Shipbuilders of the World, 125 Years of Harland and Wolff,
Press, Belfast, Ireland, 1986.
K. Felkins, H.P. Leighly, Jr.,
and A. Jankovic:
1998, vol. 50(1), pp. 12–18.
B.L. Bramfitt, S.J. Lawrence, and
H.P. Leighly, Jr.:
Iron & Steelmaker,
1999, vol. 26(9),
Copyright © 2004 ASM International®. All Rights