En ===> liquid + Fo P：转熔点 或 包晶点
Fractional Crystallization
P点包晶反应
钠长石-钙长石相图
完全固溶体相图
碱性长石系列 ？ 斜长石系列 ？
6
（3）二元系加热熔化过程
Equlibrium Melting of Composition
For equilibrium melting the liquid produced on melting stays in contact with the solid being melted, thus the final liquid will have the same bulk composition as the initial solid. For the melting path followed refer to the figure indicated in the above link.
Fractional Melting of Composition
For fractional melting, the liquid produced on melting is removed from the system and is not able to equilibrate with the residual solid.
Pure Fractionation X1→X2→L3→L4→E
Forsterite-Silica system
Forsterite-Silica System
1) Enstatite (En) melts incongruently; 2) Liquid immiscibility at high temperatures for silicarich melts; 3) Effects of increasing pressure are En becomes a congruently melting compound; 4) Increase P results in the disappearance of this liquid immiscibility.
Equlibrium Melting of Composition
Y5 Y3 Y1
7
Fractional Melting of Composition
区域熔炼
作业3 标注相区，并记录图中j’、k’ 组成熔液析晶过程
k’ j’
j
k
8
Phase Diagram for Binary Systems
（1）二元系相图的类型
T T
f = c + p +1
T、×P
T
对于凝聚态
P
A
组成
B
A
B
1
T
L
液相线 A+L
固相线 A+B
A
液相线 L+B
E
B
E：低共熔点
杠杆规则
Lever Rule
化合物类型：一致熔融化合物、不一致熔融化合物
The melting of intermediate compound
8. Complete SS and a maximun
5. Complete Solid Solution, no minimun or maximum
6. Complete SS with a minimun and a solvus
标注相区
L
AB+L
A3B2+L
L+B
AB+B A+L
A+A2B A2B+A3B2 L+A3B2
2
二元系相图类型
不含固溶体体系
二元系相图类型
含固溶体体系
3. No SS, incongruently melting compound
4. No SS, more than 1 incongruently melting compound
二元系相图类型
含固溶体体系
7. Partial SS and a eutectic
1
矿物材料研究方法及相图基础
1.1 矿物材料研究方法 1.2 单元系相图 1.3 二元系相图 1.4 三元系相图简介
主要内容
（1）二元系相图的类型
杠杆规则、相区标注、化合物类型（一致熔融化 合物、不一致熔融化合物）
（2）二元系析晶过程
简单低共熔相图、转熔相图、完全固溶体相图
（3）二元系加热熔化过程
1.3 二元系相图
-Fractional Crystallization
- where the liquid and crystals do not remain in contact, the crystals are prevented from reacting with the liquid. The final liquid composition is not the same as the initial bulk chemical composition.
Congruently Melting Compound
AB2 → L
Incongruently Melting Compound
XY2 → L + Y
二元系相图类型
不含固溶体体系
1. Simple eutectic, no SS
2. No SS, congruently melting intermediate comp源自undA3B2+AB
A3B2+B
A
A2B A3B2 AB
B
3
标注相区
α
A
L
β
B
（2）二元系析晶过程
Equilibrium Crystallization
-where the liquid and crystals remain in contact with each other, and there is no change in the bulk chemical composition as a result of crystallization.
Fe-Fe3C相图
简单低共熔相图
Equilibrium Crystallization
X1
Anorthite
X2 X3
X5 Diopside
4
不完全固溶体+低共熔相图
Fractional Crystallization
X1→X2→ X3→ L3→ X4→L4→X5 Batch Fractionation
镁橄榄石
顽辉石
石英
5
含不一致熔融化合物相图
Simplified Fo-Si System
a single binary eutectic (E) at a temperature = 1543°C
liquid ===> En + Qtz E：低共熔点 a binary peritectic (P) at a temperature = 1557°C.