上游充通大粤 SHANGHAI JIAO TONG UNIVERSITY 9.8 Compounds 1600 1414 Mg:Si L 1200 L+Si 1087 946.7 赵 L+Mg 56.5 800 L+Mg2Si L+Mg:Si 649 638.8 MgSi+Si 1.38 Mg+Mg2Si 400 M 10 20 30 40 50 60 70 80 90 Si w(Si)/% 6
9.8 Compounds 6
1800A 上游充通大￥ 160U叶 SHANGHAI JIAO TONG UNIVERSITY 1400F 1200外 1186 66.3 10.5 B 1000 Points:A:Tm of Pt 800 B:Tm of Ag 600 P:Peritectic point。 400L The alloy at D is called peritectic alloy(包晶合金) (x)/% 2> Line:ACB:liquid phase line ADPB:solid phase line DE:solid solution curce of Ag in Pt PF:solid solution curce of Pt in Ag DPC:horizontal,called peritectic line. The alloys on this line is under peritectic reaction:Lc+pBp Regions:three single phase regione:L、ak、β solid solution of Ag in Pt β：solid solution of Pt in Ag three double phase regions:Ltau、L+β、a+B。 7
A Points：A：Tm of Pt B：Tm of Ag P：Peritectic point。 The alloy at D is called peritectic alloy(包晶合金) Line：ACB：liquid phase line ADPB：solid phase line DE：solid solution curce of Ag in Pt PF： solid solution curce of Pt in Ag DPC：horizontal, called peritectic line. The alloys on this line is under peritectic reaction: LC + αD →βP Regions： three single phase regione： L、α、β α：solid solution of Ag in Pt β：solid solution of Pt in Ag three double phase regions：L+α、L+β、α+β。 B 7
上游充通大粤 e SHANGHAI JIAO TONG UNIVERSITY Usage of phase diagrams 1 al with multi-components system -phase rule -Phase diagrams: 1.equilibrium phases under different conditions 2.What will happen to the phases while the Temp,pressure and/or composition changes 3.The conditions for phase transformation To investigate new materials Critical evidence to analyze the alloy components,chemical composition, and to design the manufacturing and thermal treatment process 8
Usage of phase diagrams 1 To deal with multi-components system -phase rule -Phase diagrams: 1.equilibrium phases under different conditions 2.What will happen to the phases while the Temp, pressure and/or composition changes 3.The conditions for phase transformation To investigate new materials Critical evidence to analyze the alloy components, chemical composition, and to design the manufacturing and thermal treatment process 8
上游充通大￥ SHANGHAI JIAO TONG UNIVERSITY Usage of phase diagrams 2 To purify a material in M 液相 certain region 固溶体 The impurities in the solid is less than in liquids 20B 熔 熔 图5-15区域熔炼示意图 9
Usage of phase diagrams 2 To purify a material in certain region The impurities in the solid is less than in liquids 9
上游充通大粤 SHANGHAI JIAO TONG UNIVERSITY Usage of phase diagrams 3 ·估算热力学数据，如 熔化热 一从相图上查出一定成 分的合金系统中，作 L(T-T) 为溶剂的金属熔点降 XB= 低了多少度，然后用 RTR 稀溶液凝固点下降的 依数性公式，即可估 算溶剂金属的摩尔熔 化焓 10
Usage of phase diagrams 3 10