Phase transition due to pressure
The state of a substance depends not only on the temperature but also on the pressure. An example of this is skating on ice.
The whole process is augmented by a temperature effect: The sliding friction of the blades on the ice results in a very small amount of heating, which allows the ice to melt even more readily.
Information and ideas:
Ice researchers still do not always agree absolutely in which cases pressure is the dominant effect when skating on ice and in which cases friction. Scientific studies are still being carried out on this subject.
Assignment: Students should explain the melting process due to pressure using the p-T diagram.