AEROSPACE MATERIALS

1. Introduction to Materials (2 hour)
1. Types of Materials
2. Relationship among structures, processing and properties
3. Material selection for design
2. Atomic Structure, arrangement of atoms (8 hours)
1. Structure of atom, periodic table, binding energy and bonds
2. Atomic arrangements
1. Crystal and amorphous
2. Crystal geometry
3. Unit cell
4. Lattices, points, directions, planes in a unit cell
5. Millers’ indices
6. Allotropic and polymorphic transformation
3. Imperfections in the atomic arrangement
1. Imperfections
2. Point defects, surface defects, dislocation
3. Deformation by slip and twinning
4. Schmid’s Law
4. Movement of atoms in materials
1. Fick’s First Law
2. Fick’s Second Law
3. Mechanical Properties and their tests (8 hours)
1. Tensile Test
1. Load- Deformation Diagrams
2. Engineering stress-strain diagram for ductile and brittle materials
3. True stress-strain diagram
4. Properties tested from tensile test, temperature effects
5. Brittle behavior and notch effects.
2. Hardness Test
1. Main hardness testing methods
2. Brinell, Rockwell, Vickers, Knoop test
3. Microhardness test, Hardness conversion table
3. Impact Test
1. Toughness
2. Types of impact test, Charpy and Izod test
3. Significance of Transition - Temperature curve, Notch sensitivity
4. Fatigue Test
1. Fatigue failure
2. S-N curve, Endurance limit, Fatigue strength versus fatigue limit
3. Preventions
5. Creep Test
1. Creep failure
2. Creep and stress rupture curve
3. Effect of temperature and stress level on creep life
4. Preventions
4. Deforming process for materials (6 hours)
1. Cold work
1. Cold work and its types
2. Strain Hardening and the stress-strain curve
3. Properties versus degree of Cold-work
4. Microstructure and residual stress in cold worked metals
2. Treatment after Cold-work
1. Annealing
2. Three stages of annealing (recovery, recrystallization and grain growth)
3. Hot-work
1. Hot-work process and its types
2. Comparison between Hot-work and Cold-work
5. Solidification, Phase Relations and Strengthening Mechanism (7 hours)
1. Solidification
1. Nucleation and grain growth
2. Dendrite formation
3. Cooling curve
4. Under-cooling Cast structure
5. Solidification defect
6. Solid solutions, Solid solutions strengthening
2. Phase relations and equilibrium
1. Phase, phase rule
2. Phase diagram containing three- phase reactions
3. Lever rule, four important three phase reactions, and Eutectic phase diagram
3. Strengthening Mechanism
1. Alloys strengthening by exceeding solubility limit
2. Age hardening or precipitation hardening
3. Residual stress during quenching and heating
6. Iron – Iron Carbide diagram and Heat Treatment of Steels (8 hours)
1. Iron – Iron Carbide Diagram
1. Applications and limitations of Iron– Iron Carbide Diagram
2. Different mixtures and phases ( ferrite, austenite, pearlite, martensite)
3. Classification of steels and cast iron referring to Iron- Iron Carbide Phase diagram
2. Simple Heat Treatments
1. Annealing and its types ( Full annealing, homogenizing, spheroidizing), their method, applications
2. Normalizing method and its application, comparison between annealing and normalizing.
3. Quenching ( method and application), quenching medium, hardenability,Jominy test, TTT diagram, CCT diagram
4. Tempering, its types, applications
5. Different types of surface hardening processes, nitriding, carburizing, cyaniding
7. High Performance Aircraft Materials (8 hours)
1. Terminology Relating to Aircraft Materials
2. Non-Ferrous Alloys
1. Aluminum Alloys
2. Magnesium Alloys
3. Copper Alloys
4. Nickel Alloys
5. Cobalt Alloys
6. Titanium Alloys - Properties and Applications
3. Classification of heat resistant materials
4. Inconel Monal& K-Monal, Nimonic and Super Alloys
5. Identification of Failure Debris
8. Design of High Temperature Super-Alloys (4 hours)
1. Refractory metals and their alloys
2. Design of Turbine Blade Materials
3. Thermal Barrier Coating Technology
4. Single Crystal Superalloys
9. Composite Materials (8 hours)
1. Fibers
2. Matrix
3. Mechanics of Composite Materials
1. Macro Mechanical Behavior of a Lamina
2. Micro-Mechanical Behavior of a Lamina
3. Macro-Mechanical Behavior of a Laminate
10. Environmental Effects (1 hour)
1. Galvanic and Stress corrosion, Corrosion protection

Practical:

1. Macro examination of metals: Macrography to determine uniformity of composition, method of manufacture, physical defects.
2. Micro examination (Metallography)
1. Selection and preparation of the specimen.
2. Application of heat treatment (full annealing, normalizing, quenching, tempering), etching, observation through metallurgical microscope to different specimens of ferrous and non-ferrous alloys.
3. Examination of Failure: Fatigue, Creep
4. Tests: Hardness Test (Brinell, Rockwell, Micro-hardness)
5. Mechanical Testing (tensile, compressive, impact) for ceramics and polymers
6. Strength Testing of Adhesives
7. Literature Review on current aviation materials (Individual topics for each students)

References:

1. Tariq Siddiqui, "Aircraft Materials and Analysis" McGraw-Hill Education, 2014
2. Adrian Mouritz, "Introduction to Aerospace Materials" Woodhead Publishing
3. D. R. Askeland, “The Science and Engineering of Materials”, PWS- Kent Publishing Co., Boston,
4. Westerman Table ( IS Standard)

Evaluation Scheme:
The questions will cover all the chapters of the syllabus. The evaluation scheme will be as indicated in the table below: