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This is the conclusion of David Pye's blog on the time-temperature-transformation (TTT) curve.

The observation of the iron-carbon equilibrium diagram can only be a guide to the process temperature selection simply because the diagram is based only on iron and carbon without any additional alloying elements (in equilibrium). Alloy additions to the alloy steels will disturb what is observed from the iron-carbon equilibrium diagram, and no industrial process is in equilibrium.

Time waits for no man. Time cannot be saved. Time only moves on, even as we speak. The process temperature will determine what microscopic transformation will occur (including grain growth). Transformation is the resulting metallurgical effects of the process time and temperature selected (Fig. 1).

David Pye's series on the Titanic and its tragic sinking concludes.

Something to be aware of is that any transatlantic crossing was always a fast crossing. Now we have the factor of the increased vessel speed, at approximately 21 knots, becoming an influencing factor.

David Pye's series on the Titanic continues with a discussion of the riveters.

It is just short of 110 years since the tragic sinking of the unsinkable ship, the RMS Titanic. During construction, some 2,000 hull plates were used along with approximately 3 million rivets to join the hull plates together.

Conduct the temperature uniformity survey (TUS) on the furnaces each week. Be sure to remember to conduct the TUS anytime that a repair has been completed on the furnace. 

Temperature uniformity within a furnace can be defined as: “a uniform temperature set to operate within a specific tolerance band to create conditions under which a final uniform resulting metallurgy will be accomplished in the treated component.”

If the objective of the hardness test is to measure the depth of case, it will be necessary for the test operator to understand the definition of case depth. Case depth is the formed case that has occurred to whatever depth was specified.