Flawed Steel Research Finds Steel Used In Titanic Was High In Sulfur And Prone To Fracturing At Temperatures Of Icy Seawater
Thomas Andrews was a master of detail. As managing director and head of the design department of the British ship-building company Harland and Wolff, he oversaw the construction of the Titanic, then the world’s largest passenger ship, in 1912. From the hull design to the correct number of screws for the hat hooks in the staterooms, nothing escaped his attention.
But 83 years ago, at 2:20 a.m. on April 15, 1912, two hours and 40 minutes after hitting an iceberg, the Titanic sank, taking 1,517 men, women and children with it. Among them was Thomas Andrews.
The last anyone could recall, Andrews was sitting in the first-class smoking room, gazing off into space as if in total disbelief at what was happening.
Andrews could not have known because in his time there was no way to test for it, but the steel comprising the Titanic’s hull was flawed.
Last month at a meeting of the Chesapeake Section of the Society of Naval Architects and Marine Engineers in Arlington, Va., a scientific report based on five years of research on the Titanic was presented. It gave new evidence that the steel used in the ship’s construction, as well as that used on other large ships of the day, was particularly high in sulfur.
Under extremes in temperature the steel was susceptible to a condition called “brittle fracture.” It was brittle fracture, the scientists and engineers now believe, that caused the Titanic’s hull to shatter on impact with an iceberg. It was also brittle fracture that contributed to the cracking apart of the Titanic and its rapid descent, the report asserted.
The details of the sinking of the Titanic have been a subject of controversy from the moment the world learned of the tragedy.
The Titanic had been touted as the world’s safest ship prior to its fatal maiden voyage. Until the remains of the great ship were discovered by oceanographer Robert Ballard of Woods Hole Oceanographic Institution, Woods Hole, Mass., in 1985, all anyone could do was speculate.
Two government investigations had been initiated - one in England, the other in America - soon after the Titanic sank. Using information from those inquiries, most authorities thought that when the great liner hit the iceberg that sealed its fate, a 300-foot gash opened up along the bottom of the ship. They also believed that the ship went to the bottom largely intact.
Ballard’s expedition proved the theory of an intact Titanic wrong. What he found 12,950 feet below the Atlantic was a shattered ship, the stern or back section resting 1,870 feet from the bow and facing the opposite direction.
Some survivors had always contended that the Titanic had split between the third and fourth funnels. This event happened, Ballard believed, at or just below the surface.
But Ballard had not discovered why the ship, designed to be unsinkable, had gone down so fast. In 1987, in his book “The Discovery of the Titanic” (Warner/Madison Press; $29.95; 227 pp.), Ballard wrote that because the bow section of the Titanic is buried deep in the mud, the original impact area of the iceberg cannot be seen.
Harold Reemsnyder, a structural engineer who is Bethlehem Steel Corp.’s senior research consultant on fatigue and fracture of steel, reviewed several of the preliminary papers done for the Titanic study.
As Reemsnyder describes it, most shipbuilding engineers in 1912 would have been unaware of the concept of brittle fracture.
“There was some work being done at that time in the French navy on the problems with the ductility (the amount and type of stress metal can take before it breaks) of steel,” Reemsnyder said.
“But most engineers in 1912 went by what they had a learned in their work. They just had a ‘feel’ for avoiding undue stress. But probably they were unaware of what they were dealing with in something as large as the Titanic.”
The scientific expedition that led to last month’s report began in 1991. Dubbed the “IMAX dive,” it combined science and entertainment. Using two Soviet Mir submersibles that could stay under water for 20 hours, its primary purpose was to make an $8 million, 70 mm movie, “Titanica,” for the six-story-tall screens of IMAX theaters.
But the dive included what Popular Science magazine calls in its February 1995 issue “the first (and so far the only) purely scientific team that has visited the site.”
The scientists were led by Steve Blasco, an ocean-floor geologist with Canada’s Department of Natural Resources. Testing of the Titanic’s metal was done at the Metals Technical Laboratory of Ottawa called CANMET and the Canadian Department of Defense Laboratory in Halifax, Nova Scotia, under direction of the Bedford Institute of Oceanography in Dartmouth, Nova Scotia.
No passenger-related items were retrieved. But on the sub’s last dive it picked up a small chunk of hull steel one-inch thick with three rivet holes, each 1 1/4 inch across.
The scientists wanted to test the steel, but for comparison they needed a piece of the Titanic’s steel that had never been to sea.
By chance, Bud Weatherup, a cook in the cafeteria of the Nova Scotia Research Corp., heard about the search for the Titanic’s steel. He had a paperweight his father had made from a divot, a small piece of steel that had fallen from the Titanic’s rivet holes when the ship was being built in Belfast.
After shaving a small piece off of the paperweight, metallurgists compared it under a microscope with the piece taken from the ocean and determined that the physical composition was the same.
In a test designed to discover brittleness, a piece of steel from the Titanic and a piece of modern ship steel were placed in a bath of alcohol with a temperature of 29 degrees, the same temperature as the sea water the night the Titanic sank.
Removing the modern steel from the bath, a metallurgist placed it in a holder. Then a pendulum 2 1/2 feet long, weighing 67 pounds and electronically able to record details about the force of impact was swung against it. The metal reacted with a thud, bending into the shape of a V.
Then the piece of steel from the Titanic was placed in the holder.
“This time there is no thump,” reports Popular Science. “The pendulum strikes the piece with a sharp ‘ping,’ barely slows, and continues up on the swing while the sample, broken in two, sails across the room to smack a metal wastebasket.”
The tests made it clear to scientists that there was a flaw in the Titanic’s steel. They discovered that by today’s ship-building standards, the sulfur content in the metal was extremely high. This made the steel more subject to fracture.
The Titanic’s steel was manufactured at D. Colville & Company, Motherwell Works, located in Scotland. The company provided much of the metal that went into ships built by Harland and Wolff and other major British ship-building companies from 1900 to 1933. The report notes it was fairly standard steel for that time.
It was not until 1947 that brittle fracture was first recognized as a problem.
“We have to understand that this was not regarded as cheap substandard steel in 1912,” said Peter Hsu, a structural engineer with Techmatics Inc., a naval consulting firm that contributed to the final report. “It met the standards set at that time.”