Phase Diagrams
Pressure Effects
· Pressure also influences the (p, T) range over which the phases of alloy systems may exist. The diagram illustrates this at three pressures P1, P2, and P3, for the binary A-B alloy system that forms the compound AB3
· As the pressure increases from P1 to P3 the stability of AB3 increases. At P1 the compound decomposes into A + B as the temperature is increased through the lowest invariant reaction temperature. At P2, the transformation at the higher invariant reaction temperature is an incongruent melting to a liquid and solid B. For the pressure P3, the reaction now becomes a congruent melting with the liquid having the same composition as the solid from which it comes.
From: White, "Properties of Materials,"
Oxford University Press (1999)