A SHATTERING TALE

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It was common belief that when the Titanic hit the iceberg that an enourmous 'gash' was ripped into her hull and thus sealing her fate. However, new evidence would seem to suggest otherwise. Testing of metal samples taken from the Titanic wreck have revealed shocking new facts into what really sank the great ship. The following article, taken from the February 1995 edition of Popular Mechanics, explains this:

On the last dive of the trip, one of the Mirs came across a chunk of metal that looked like a part of the hull. The scientists has agreed beforehand that they would bering up no human artefacts; they felt that the site should be considered consecrated as a burial ground, and that retrieval of personal items would smack of grave robbing. But for strictly scientific purposes, they did want to bring up a sample of hull.

And there it was, resting on a ripple of the ocean floor silt as though placed there the previous month: a frisbee size chunk an inch thick, with three rivet holes, each an inch and a quarter across. Back aboard the mother ship, with the surface grime carefully squirted off the piece with a high pressure water jet, researchers were surprised to see remnants of the original paint.

By now, that piece of steel should have been corroded nearly to oblivion. But when a metallurgist saw it later, he had an immediate explanation: "Of course: there's no oxygen down there." Then Blasco pointed out that fish were swimming about, and the metallurgist stopped talking.

Sow how could there have been so little corrosion? "It somehow involves temperature and pressure" says Blasco. "That's not a very good explanation, but it's all we have for now."

Of even more interest to those intriqued by the question of the ship's unseemly rapid sinking was the condition of the edges of the hull piece: jagged, almost shattered. And the metal itself showed no evidence of bending. High quality ship steel, metallurgists know, has a lot more give, more ductility, than most people imagine, and probably wouldn't break. Yet the edges of this sample looked almost as though they were made of broken china.

Three years later, now in the Halifax testing lab, I pick up that hunk of the Titanic from a work table. It's been sitting there among broken gears, split I-beams and ruptured flanges from other ships, representing various naval problems, and it looks like junk. I remind myself that its the only one of its kind in the world. The 80 year old paint is splotchy brown, with an underlying smear of lead oxide, now a pinkish orange.

One edge is ruler straight and shiny, where a strip of metal has been sliced off. A few test pieces, cigarette sized "coupons" have been fashioned from the strip. Some have already been destroyed in preliminary testing in another government laboratory in Ottawa. The last piece will soon by mounted in a device that will conduct what is known as a Charpy test. In the lab are Blasco and another of the Imax team, Duncan Ferguson, a 34 year old mechanical engineer.

The metallurgist in charge is Ken KarisAllen, 35, a government specialist in cracks and corrosion. He's energetic, quick moving, almost taut, and when he speaks of his Charpy machine, he does so with fondness.

A Charpy tests brittleness, he explains, nonchalantly pushing the machine's huge pendulum. Testing is simple: As a coupon is held tightly against a steel holder, the pendulum - 67 pounds and 2.5 feet long - swings down and thumps aginst the sample, sometimes breaking it. The pendulum's point of contact is instrumented, with a readout of forces electronically recorded in millisecond detail.

KarisAllen will test two coupons: one, a sample of standard good quality steel used in modern ships; the other a slice from the Titanic. "If things go as I foresee," he says, "the first piece wil go 'thud.' The second will 'tinkle'."

Both coupons are resting in a bath of alcohol at -1C degrees - to simulate the water temperature of 80 years ago. KarisAllen must rush the test piece from the bath to the holder in five seconds.

He hauls up the weight and locks it in place. "OK?" he asks, and looks around the room. "Here goes."

With a pair of stainless steel tongs, he lifts the first piece from the bath, and whisks it to the holder. He reaches for a red release handle and yanks. The pendulum swings down and thuds to a halt. The test piece has been bent into a "V."

This time there is no thump. The pendulum strikes the piece with a sharp "ping", barely slows and continues up on its swing while the sample, broken in two, sails across the room to smack a metal waste basket.

Traces on the computer screen confirm what the metallurgists suspected and have now seen; the Titanic's hull steel is brittle. When it met the iceberg, the hull plates simply didn't bend inward. They fractured.

The steel is embrittled not from sitting on the ocean floor for most of a century. It was that way when it came from the steel plant, and became even more brittle slicing through that -1C degree water. "To make present day steel that brittle," says KarisAllen, "I'd have to lower the temperature to -60C - -70C degrees."

"Back then nobody understood the concept of brittle fracture," adds Ferguson. "They tested the steel for strength [the maximum stress a material can handle before it breaks], and if it passed, that was that. What they did not know then was the high sulphur content makes for brittleness, and Titanic steel was high even for the times. "It's full of sulphide occlusions called 'stringers,' and it would never get out of the yard today. It wouldn't even make good rebar, which is pretty lousy steel."