The Failure of the Titanic

The Failure of the Titanic

3.24.2004

Hadi Sattari

Armando Colimodio

According to Marrian Webster’s dictionary the primary definition of failure is: “1. a state of inability to perform a normal function.” The Titanic was a method of transportation for passengers and mail from Europe to North America. During the first quarter of the 20^th century steamships were the primary method for transatlantic voyages. The Titanic was to be the largest and most awesome steamship in the world. It cost $7.5 million dollars to build. It had a length of 882.5 ft, weighed 46,329 tons, and would burn 650 tons of coal per day to fire the 29 boilers and the 159 furnaces, and able to produce 51,000 hp. A ship of this magnitude had to be well designed and engineered. So why was this unsinkable ship unable to withstand the force of the iceberg that struck it’s hull?

When the titanic collided with the iceberg it was punctured causing a 100 meters gash and an area of 1.2 meter squared. Should the hull of the unsinkable ship been able to withstand the impact of this iceberg? The steel of the Titanic must be studied to analyze if it was sufficient for its use. The steel of the ship was recovered by University of Missouri-Rolla and the composition was determined. Shown below:

*Table II. The Composition of Steels from the Titanic, a Lock Gate, and ASTM A36 Steel*
	C	Mn	P	S	Si	Cu	O	N	MnS: Ratio
*Titanic* Hull Plate	0.21	0.47	0.045	0.069	0.017	0.024	0.013	0.0035	6.8:1
Lock Gate*	0.25	0.52	0.01	0.03	0.02	—	0.018	0.0035	17.3:1
ASTM A36	0.20	0.55	0.012	0.037	0.007	0.01	0.079	0.0032	14.9:1
*Steel from a lock gate at the Chittenden ship lock between Lake Washington and Puget Sound, Seattle, Washington.

(JOM Journal)

The analysis of the composition yield high levels of Phosphorous, nearly four times that of modern steels. Sulfur levels were found to be nearly twice as high as steels used today. Nitrogen content was also found to be low. According to JOM (The Member Journal of
The Minerals, Metals & Materials Society) article, this implied that the steel construction did not use the Bessemer process. This caused the steel to become very brittle at low temperatures. The metal was forged in Glasgow, in the UK, and was likely produced in an acid-lined open hearth furnace. This would cause MG:S ratio of 6.8:1, which causes insufficient metal properties, which made the ship unable to withstand such an impact. Another effect of the low phosphorous levels was that it increased the probability of fractures. Also low manganese levels result in less ductile properties and therefore more vulnerable to fracture. Samples from the Titanic hull show that the transition from ductile to brittle temperatures was in the vicinity of 32 deg C. Today’s steels undergo this transition at temperatures of around minus 27 deg C. Considering temperatures of the Atlantic are below freezing this gives question to the cause of failure for the Titanic. The steels seem to be clearly insufficient for the purpose they were used for.

Another material property affected by the higher manganese content and low sulfur content is the impact energy property versus temperature. Again this is a result of the high temperature transition from ductile to brittle. We can see in the graph below that the specimens made from ASTM A36 steel have the best impact properties. The ductile-brittle transition temperature determined at an impact energy of 20 joules is -27°C for ASTM A36, 32°C for the longitudinal specimens made from the Titanic hull plate, and

56°C for the transverse specimens. That shows that the steel used for the hull was not suited for low temperatures.

(JOM journal)

It is clear to see that the reasons for the Titanic’s failure were due weak and improper metal properties. The engineering just was not what it should have been for a ship of that size and task.

By today’s metals it is clear to see in hindsight that the properties were sub par. However, at the time there were probably not many metals that were any better. According to the JOM article the metals that constructed the hull of the Titanic were some of the best of the time. They were unable to withstand the impact however, and therefore this was a mechanical failure. One wonders if today’s metals would have been able to save the unsinkable ship. The new metals and the better properties would have saved some lives if not all.
References

Bruzel, Alan. Analysis of Steel from The Titanic. http://dwb.unl.edu/Teacher/NSF/C10/C10Links/chemistry.about.com/library/weekly/aa022800a.htm 02/28/00.

Felkins, Katherine. H.P. Leighly Jr and A. Jankovic. The Royal Mail Ship Titanic: Did a Metallurgical Failure Cause a Night to Remember? http://www.tms.org/pubs/journals/JOM/9801/Felkins-9801.html#ToC6 . Journal appears in JOM 50 (1) (1998), pp. 12-18.

Merriam-Webster's Collegiate Dictionary. 10th ed. 1999.