Metallurgy

Code:

EM0017

Acronym:

MM

Keywords
Classification	Keyword
OFICIAL	Materials

Instance: 2007/2008 - 1S

Active?	Yes
Responsible unit:	Materials and Technological Processes Group
Course/CS Responsible:	Master in Mechanical Engineering

Cycles of Study/Courses

Acronym	No. of Students	Study Plan	Curricular Years	Credits UCN	Credits ECTS	Contact hours	Total Time
LEM	0	Plano de estudos de transição para 2006/07	2	5	5	56	133
MIEM	202	Syllabus since 2006/2007	2	-	5	56	133
		Plano de estudos de transição para 2006/07	2	-	5	56	133

Teaching language

Portuguese

Objectives

The discipline of Mechanical Metallurgy has as main objectives to give students a general view about the metallurgical variables affecting the mechanical behaviour of metallic materials. Both mechanical and metallurgical aspects of the following topics are studied:

1)Metal structure and crystallization
2)Inelastic deformation
3)Strength mechanisms
4)Constitution of metallic alloys and phase diagrams
5)Mechanical testing

Program

I -Metal structure and crystallization

1. Resistance of Materials. Basic Assumptions
2. Elastic and plastic behaviours
3. Stress and strain concepts
4. Tension versus compression strains
5. Ductile vs. fragile behaviour
6. Introduction to the tensile test
6.1. Elastic behaviour: stiffness of a material. Resistance to plastic deformation and fracture. Ductility. Resilience and toughness.
6.2. Parameters for mechanical properties: practical
6.3. Engineering and true stress-strain curves. Strain Hardening exponent.
7. Crystals geometry
8. Structure cells. Miller indices
8.1. Miller Indices for planes and directions.
8.2. Linear, planar and volumetric packing factors
8.3. Interplanar distances
8.4. Planes and directions on the close-packed hexagonal crystallographic system


II – Monocrystalline Plastic Deformation

1. Crystal imperfections: point, linear and surface defects
1.1. Linear lattice defects: edge and screw dislocations
1.2. Planar defects: stacking faults
2. Deformation by slip
3. Critical resolved shear stress for slip
4. Deformation by slips versus deformation by twinning
5. Deformation bands
6. Microdeformation
7. Strain hardening behaviour in single crystals


III –Plastic Deformation in Policrystals

1. Importance of grain boundaries in plastic deformation: Petch Hall Law
2. Yield Point phenomena
3. Strain Hardening ageing
4. Effect of temperature: Portevin-Le Chatelier Effect

IV – Phase Diagrams
1. Constitution of alloys: Pure metals, intermediate phases, intermetallic and interstitial compounds and solid solutions.
2. Free energy for binary phases in equilibrium conditions. Gibb´s law. Application of the lever Rule.
3. Phase Diagrams types
3.1. Unlimited solubility in solid state
i) Relative quantities of phases
ii) Thermal analysis
iii) Superstructures
3.2. Insolubility in solid state. Eutectic reactions without terminal solid solutions
i) Normal and abnormal eutectics
ii) Intermetallic compounds

3.3. Parcial solubility in solid state: eutectic reaction with terminal solid solutions. Peritectic reactions
3.4. Other reaction types in phase diagrams
3.5. Solid state reactions. Eutectoid and peritectoid reactions
4. Non-equilibrium cooling. Origin of coring


V – Hardening Mechanisms

1. Solid solution hardening
2. Deformation of composites. Particulate and fibrous reinforcement .
3. Age hardening processes. Heat treating Aluminium alloys.
4. Martensitic reaction hardening. Heat treatments of steels.
5. Cold worked microstructures
5.1. Annealing of cold worked structures: recovery and recristalysation
5.2. Preferred orientation: crystallographic and mechanical textures
VI – Mechanical Behaviour
1. The hardness test: Brinell, Vickers and Rockwell tests. Elastic hardness tests: Shore.
2. Dynamic toughness tests. Classic impact tests: Charpy and Izod tests
2.1. General conditions
2.2. Transition temperature concept
2.3. Factors promoting fragility
2.4. Fractography of fragile and ductile materials
3. Cyclic properties: fatigue tests
3.1. Introduction to fatigue of metal alloys
3.2. Material characterization in fatigue crack initiation: fatigue limit within the Woehler curves
3.3. Fatigue crack initiation based on strain measurements: Manson-Coffin and Basquin laws. Mean stress effects in fatigue initiation Notch effects in fatigue initiation
3.4. Propagation in fatigue: the Paris’ law. The stress intensity amplitude factor threshold in fatigue
3.5. Fatigue failure analysis: effects of type of loading, nominal and residual stress levels and stress raisers. Surface hardening by thermochemical treatments like carburizing and nitriding
4. Mechanical behaviour at high temperatures: creep tests
4.1. Basic creep strain vs time curves: deformation and rupture curves.
4.2. High temperature material characterization: master curves using the Larson-Miller and Manson-Haferd parameters.
4.3. High

Mandatory literature

Smith, William F.; Principios de ciência e engenharia dos materiais. ISBN: 972-8298-68-4
Dieter, George E.; Metalurgia mecânica

Complementary Bibliography

Askeland, Donald R.; The science and engineering of materials. ISBN: 0-534-55396-6
Barralis, Jean; Prontuário de metalurgia. ISBN: 972-31-1106-3

Teaching methods and learning activities

Mechanical Metallurgy is organized in theoretical and practical classes dealing with the following topics:
1 -Cristallography
2 –Mechanical Behaviour
3 –Equilibrium Diagrams
4 – Tools supporting Metallurgy

- temperature control
- metallography
- mechanical tests

Experimental work will be carried out on topics given in theoretical classes, with emphasis on metallography, mechanical tests and heat treatments that promote alloy hardening.

Evaluation Type

Distributed evaluation without final exam

Assessment Components

Description	Type	Time (hours)	Weight (%)	End date
Subject Classes	Participação presencial	56,00
Exams	Exame	4,00		2007-12-21
Experimental Studies	Trabalho escrito	30,00		2007-12-21
	Total:	-	0,00

Amount of time allocated to each course unit

Description	Type	Time (hours)	End date
Study	Estudo autónomo	45	2007-12-21
	Total:	45,00

Eligibility for exams

Class attendance (minimum 75%)

Calculation formula of final grade

Average of experimental studies marks (20%) + average of two tests (80%)

Special assessment (TE, DA, ...)

Final written exam

Classification improvement

Final written exam