Overview

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Overview
Selection
Control
Properties
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1.1 Properties

• Nature of properties
• Intrinsic
• Extrinsic
• Anisotropic
• Types of properties
• Mechanical
• Thermal
• Chemical
• Surface vs bulk

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1.2. Mechanical properties

• Youngs modulus E
• Yield strength ?y
• Work hardening
• Ductility
• Necking and necking strain
• Friction, wear and lubrication
• Fracture toughness

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1.3. Thermal properties

• Thermal expansion
• Thermal stress
• Thermal distortion
• Thermal shock
• Melting of metals
• Glass transition of polymers
• B-D transition in BCC metals

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1.4. Chemical properties

• Electro-chemical corrosion
• Bimetal corrosion
• Corrosion prevention
• Oxidation
• Purposes of alloying

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2.1 Control of properties

• Chemical methods
• Mechanical methods
• Thermal methods
• Surface vs bulk properties
• Timing

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2.2 Chemical methods

• C in steels
• C in cast iron
• Cr in stainless steels
• Cu in Al
• Carburization and nitriding
• Ni, Mn in steels
• Phase stabilizers

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2.3. Mechanical methods

• Work-hardening
• Effect on yield strength, ductility, etc
• Surface hardening
• Texture of metals
• Texture of polymers

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2.4. Thermal methods

• Age hardening
• Quenching of steels
• Surface heat treatments
• Timing, order of treatment

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2.5. Surface vs bulk properties

• Surface chemical change
• Surface cooling rate
• Surface work-hardening

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3.1 Selection of materials useful properties

• Selection for stiffness
• Selection for high yield strength
• Selection for low weight
• Selection for thermal conduction
• Performance indexing, guidelines and charts

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3.2 Failure and prevention

• Selection against thermal stress
• Selection against thermal shock
• Selection against corrosion
• Selection against oxidation
• Selection against friction
• Selection against wear
• Selection against brittle failure

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3.3 Case studies

• Cantilever
• Columns
• Mirror base
• Fly wheels
• Fans/compressor blades
• Turbine blades
• Springs and hinges
• Pressure vessel

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Case studies

• Car body
• Stamping die
• Exhaust system
• Corrosion prevention
• Oxidation prevention
• Wear prevention

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4.1 Materials

• Basic classification
• Structure of materials
• Property territories property charts
• Handbooks, status
• Designations, names and temper
• A basic repertoire

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4.2 Repertoire of metals

• Steels
• Stainless steels
• Al alloys
• Ti alloys
• Cast iron
• Cast Al
• Sheet metals, texture

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Basic properties of metals

• Density
• Modulus
• Yield strength
• Melting temperature
• Corrosion and oxidation
• Work hardening
• Ductility
• Property control/treatment

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4.3 Repertoire of polymers

• Thermoplastic vs thermoset
• PE (HDPE, LDPE, UHMWPE)
• PS
• PVC (plasticized vs unplasticized)
• PFTE
• PMMA, PC

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Basic properties of polymers

• Modulus
• Thermal properties
• Density
• Yield strength
• Ductility
• Degradation/durability
• Wear and friction

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4.4 Nature of material selection

• Divergence in property consideration
• Convergence in material selection
• Manipulation of properties