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CONCLUSIONS |
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All the evidence that I have presented in this report has pointed to the conclusion that the steel used in the Titanic hull plate is not acceptable by modern standards. The tests and analysis tecniques that have been used to form this conclusion were developed long after the Titanic was built in the early 1900's, and the science of metallurgy has advanced considerably since then. The main source of evidence that the Titanic steel does not match up to todays standards is the comparision with ASTM A36 steel, both chemically and physically. A36 steel was shown to have a more suitable chemical composition, that made it much harder to fracture, at high and low temperatures. The graph of impact energy against temperature comparing Titanic hull plate and A36 steel demonstrates that A36 would have been a much better steel to build the Titanic with, as at a temperature of -2 degrees celcius, (seawater temperature at the time of the collision), it had more than 3 times the impact strength of the Titanic steel. This is strong indication that the metallurgy of the steel played a large part in the sinking of Titanic, as the impact strength of the steel was clearly not large enough to withstand the impact energy enforced when an iceberg that was 3 to 6 times its own mass collided with it. It is not possible to say whether or not the Titanic would have sank, had it been constucted of a steel with the same metallurgical properties as ASTM A36 steel. Although, I think it is likely that even if it had been constructed of todays 'best' steel, that the Titanic would have sank, because the power and impact of the iceberg were so huge, that even the metallurgical advances of today would not be able to compare with them.
It is important to remember what William Garzke of Gibbs and Cox and his collaborators emphasized in their report of the Titanic steel; |
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'The steel used in the Titanic was the best available in 1909-1914 when the ship was built.'
No modern ship, not even a welded one, could have withstood the forces that the Titanic experienced during her breakup.' |
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These quotes from Garzke re-enforce my own conclusions about the Titanic steel. I think what Garzke is saying is a valid, non-biased point, and I cannot find any other information that contradicts his theory that the Titanic steel was the best available at the time. Therefore, I conclude that although new metallurgical techniques have shown that by modern standards, the Titanic hull plate steel was not suitable for its purpose, it was the best steel available when the Titanic was built. |
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So how would metallurgists treat the problem of designing the material for the Titanic's hull today? The answer to this question comes from my comparisons of Titanic steel with a much more suitable steel, ASTM A36. By modern standards, a steel that would be suitable for building Titanic's hull plate would have a high Mn:S ratio, ideally 15:1. It should have a lower nitrogen content than 0.0035, 0.0032 would be more suitable. The phosphorus content should be kept to a minimum, 0.01 as opposed to 0.05. The steel itself should have a low average grain diameter to make it difficult for cracks to propagate. Most importantly, the mechanical properties of the steel should be intensely tested using modern tensile testing and Charpy impact tests. The steel should be able to withstand the largest impact energys possible without fracturing, over a wide range of temperatures, from -50 to 100 degrees celcius, as the temperature of the Atlantic ocean can fluctuate over a large range.
A steel built to these regulations would certainly match up to todays high safety standards, but still, as I mentioned previously, would most likely not be able to withstand an iceberg such as Titanic was faced with. This shows that although metallurgical advances have progressed a long way since 1912, they still have a long way to go, before anyone can say that accidents at sea will never happen. |
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This is the end of my designer materials coursework. To get back to the first page, click on the following link. |
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