Which of the following is the weakest phase in amalgam reaction?
The voids phase
The trace element phase
The mercury phase
The interphase
The mercury phase is the weakest phase in the product mass, and when it exceeds a certain volume limit, there will be a drastic drop in the strength and hardness properties of amalgam, in addition to increase in flow and creep of the restoration.
Reference: Marzouk Operative dentistry, pg-106