上游充通大率 SHANGHAI JIAO TONG UNIVERSITY Principles of Materials Processing Part Ill 全属材料热处理原理 Heat Treatment Principles of Metals Lecturer:Ke Chen 2017-05-05
Principles of Materials Processing Part III - 金属材料热处理原理 Heat Treatment Principles of Metals Lecturer: Ke Chen 2017-05-05
Outline for PMP-HT 高 上游充道大粤 SHANGHAI JIAO TONG UNIVERSITY Chapter 8:Intro to Phase Transformation in Solids Chapter 9:Eutectoid and Reverse Eutectoid Chapter 10:Shear Transformation Chapter 11:Precipitation transformations K.Chen 8
K. Chen Chapter 8: Intro to Phase Transformation in Solids Chapter 9: Eutectoid and Reverse Eutectoid Chapter 10: Shear Transformation Chapter 11: Precipitation transformations Outline for PMP-HT 8
h 上游充通大粤 SHANGHAI JIAO TONG UNIVERSITY Planned Schedule 5/4/2017 Date WeekChapter Content Notes 1 5-May Fri. 11 Ch8 Intro to Phase Transformation in Solids 2 9-May Mon. Ch8 12 Intro to Phase Transformation in Solids 3 11-May Wed. Ch9 Reverse Eutectoid 4 16-May Mon. Ch9 Reverse Eutectoid Eutectoid 5 18-May Wed. 13 Ch9 Eutectoid 6 19-May Fri. Ch10 Martensitic Transformations(10.1) > 23-May Mon. Ch10 Martensitic Transformations in Steels(10.2) 14 8 25-May Wed. Ch10 Bainite Transformations(10.3) 9 30-May Mon. Dragon Boat Festival (Observed) 10 1-Jun Wed. 15 Ch10 Bainite Transformations(10.3) 11 2-Jun Fri. Quiz&Ch 8 TTT/CCT Additional Topics 12 6-Jun Mon. 16 Ch11 Precipitation and Aging 13 8-Jun Wed. Ch11 Tempering of Ferrous Martensite 14 TBA 17 Final Exam K.Chen 9
K. Chen 9
General Info 上浒充通大粤 SHANGHAI JIAO TONG UNIVERSITY > Grading:homework (20%)+quizzes (20%)+final exam (60%) ■One HW/week(~4HWs) ■ Quizzes:randomly given(~5 quizzes)-Basic consepts (listen in classroom review after class) Final exam:similar to HW questions Reading assignment: Book chapters related to HW UNIVE Additional useful information > Glossary K.Chen 10
K. Chen Grading: homework (20%) + quizzes (20%) + final exam (60%) One HW/week (~4 HWs) Quizzes: randomly given (~ 5 quizzes) - Basic consepts (listen in classroom + review after class) Final exam: similar to HW questions Reading assignment: Book chapters related to HW Additional useful information Glossary General Info 10
Outline for Chapter 8 上游充道大粤 SHANGHAI JIAO TONG UNIVERSITY Chapter 8:Intro to Phase Transformation in Solids 8.1 Classification of Phase Transformations in Solids 8.2 Features of Phase Transformations in Solids 8.3 Thermodynamics for Phase Transformation in Solids IAO TONG 8.4 Kinetics for Phase Transformation in Solids K.Chen 11
K. Chen Chapter 8: Intro to Phase Transformation in Solids 8.1 Classification of Phase Transformations in Solids 8.2 Features of Phase Transformations in Solids 8.3 Thermodynamics for Phase Transformation in Solids 8.4 Kinetics for Phase Transformation in Solids Outline for Chapter 8 11
Classification 上游充通大学 SHANGHAI JIAO TONG UNIVERSITY Based on whether there are "thermally activated atomic movements": Diffusional transformations>Majority of transformations! Diffusionless transformations>Martensitic transformation Diffusional transformations: induced by a change of temperature ■ in a solid-state alloy of a fixed bulk composition AO TONG K.Chen 12
K. Chen Based on whether there are “thermally activated atomic movements”: Diffusional transformations Majority of transformations! Diffusionless transformations Martensitic transformation Diffusional transformations: induced by a change of temperature in a solid-state alloy of a fixed bulk composition Classification 12
Classification 上游充通大兽 SHANGHAI JIAO TONG UNIVERSITY Diffusional transformations can be divided into: ■Precipitation reactions(脱溶沉淀) ■ Eutectoid transformations(共析转变) Ordering reactions(有序化转变) ■ Massive transformations(块状相变) ■ Polymorphic changes(同素异构转变（多形性转变）》 AJ JIAO TONG UNIV K.Chen 13
K. Chen Diffusional transformations can be divided into: Precipitation reactions (脱溶沉淀) Eutectoid transformations (共析转变) Ordering reactions (有序化转变) Massive transformations (块状相变) Polymorphic changes (同素异构转变(多形性转变)) Classification 13
Precipitation reactions 上游充通大粤 SHANGHAI JIAO TONG UNIVERSITY Precipitation reactions a+B a+B A (i) B A Gii) B A (ii) B a'is metastable supersaturated solid solution ■ B is a stable (or metastable)precipitate ■ a is a more stable solid solution with the same crystal structure as a',but with a composition closer to equilibrium K.Chen 14
K. Chen Precipitation reactions α’ is metastable supersaturated solid solution β is a stable (or metastable) precipitate α is a more stable solid solution with the same crystal structure as α’, but with a composition closer to equilibrium Precipitation reactions 14
Eutectoid transformations 上浒充通大粤 SHANGHAI JIAO TONG UNIVERSITY Y→a+β A Replacement of a metastable phase (y)by a more stable AC mixture of two other phases (a+β) ⊕ Eg.in steel::Y→a+Fe,C >Pearlite reaction in Fe-C Alloys K.Chen 15
K. Chen Replacement of a metastable phase (γ) by a more stable mixture of two other phases (α + β) Eg. in steel: γ→α+Fe3C Pearlite reaction in Fe-C Alloys Eutectoid transformations 15
Ordering Massive 上海充夏大￥ SHANGHAI JIAO TONG UNIVERSITY Ordering reactions a(disordered)a'(ordered) (i) B (i) Disordered dered ●Cu OAu Massive transformations B→a Original phase decomposes into one or more new phases which have the same composition as the parent (i) phase,but different crystal B (ii) B structures Stable a Metastable a K.Chen 16
K. Chen Ordering reactions Massive transformations Ordering & Massive 16 Original phase decomposes into one or more new phases which have the same composition as the parent phase, but different crystal structures Stable α Metastable α Disordered Ordered