Titanic: Engineering Facts [video]
youtube.comSurprisingly not mentioned in the video is that the failure mode of the Olympic's hull, when the Hawke collided with it, provide clues to the reason the Titanic sank so quickly. The heads of the rivets holding Olympic's hull plates popped off (metallurgical analysis showed too much slag in the rivets, making them brittle). Recall that Olympic and Titanic were under construction at the same time, in the same shipyard. Most likely when Titanic hit the iceburg, the rivets holding her hull plates also popped loose, creating much larger gaps in the hull than would have occurred simply from a "puncture".
http://www.nist.gov/mml/msed/titanic_021798.cfm http://en.wikipedia.org/wiki/Tim_Foecke#Work http://www.educationworld.com/a_lesson/newsforyou/pdfs/newsf...
Not just in the rivets, in the plates themselves.
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. It is apparent that the steel used for the hull was not suited for service at low temperatures. The seawater temperature at the time of the collision was -2°C.[1]
Ductile-brittle transition wasn't understood at all in 1912. Mass production of steel only goes back to 1886 or so. Before that, good steel was an exotic, expensive material, like titanium is today. The first scientific work on ductile-brittle transition is from the 1920s, years after the Titanic. The Charpy test for brittleness was developed in 1900, but this was before refrigeration, so running a Charpy test on chilled metal was tough unless you were in an very cold climate. One early metallurgist spent a year in a very cold climate to do just such research.
[1] http://www.tms.org/pubs/journals/jom/9801/felkins-9801.html
This was a very enjoyable and well-produced short video.
Just yesterday I spent 2 hours at the Titanic exhibit at the Luxor in Las Vegas. Nothing could have prepared me for seeing the "Big Piece" up close (https://www.youtube.com/watch?v=wuxQ9jV_N8k). It is both deeply fascinating and profoundly sad to stand just inches from it.
Have you watched any of Bill's other videos? His early stuff is full of a lot of corny humor, but really excellent explanations of cool engineering found all around us.
The last few videos have been much higher in production value, and go into much more depth on really fascinating topics.