- •1. TABLE OF CONTENTS
- •2. MATERIAL PROPERTIES
- •2.1 TERMINOLOGY
- •2.2 MICROSTRUCTURES
- •2.2.1 Atomic Structures
- •2.2.1.1 - Crystal Structures
- •2.3 IRONS AND STEELS
- •2.3.1 Types of Steel
- •2.3.1.1 - Alloying Elements
- •2.3.2 Making Steels
- •2.3.2.1 - The Ores
- •2.3.2.2 - Coke
- •2.3.2.3 - Flux, Slag
- •2.3.3 The Blast Furnace - How To Make Pig Iron
- •2.3.4 How To Make Steel
- •2.3.4.1 - Electric Furnaces
- •2.3.5 Forming The Steel
- •2.3.6 Stainless Steel
- •2.4 NONFERROUS METALS AND ALLOYS
- •2.4.1 Aluminum
- •2.4.2 Titanium
- •2.5 HEAT TREATING
- •2.6 PAUL JOHNSON NOTES FOR EGR 250
- •2.6.1 Atomic Bonding and Structure
- •2.6.1.1 - Atomic Structure
- •2.6.1.2 - Periodic Table
- •2.6.2 Ideal Crystal Structure
- •2.6.3 Crystal Imperfections
- •2.6.4 Diffusion
- •2.6.5 Mechanical Properties of Metals
- •2.6.6 Dislocations and Strengthening Mechanisms
- •2.6.7 Phase Diagrams
- •2.6.8 Phase Transformations
- •2.6.9 Metal Alloys
- •2.6.10 Ceramics
- •2.6.11 Electrical Properties
- •2.6.12 Thermal Properties
- •2.6.13 Magnetic Properties of Materials
- •2.6.14 Optical Properties of Materials
- •2.7 PRACTICE PROBLEMS
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2.Electroluminescence (LED)
a.Electron - hole recombination at p-n junction can produce photon of light b.Optical range of emission
1.1.8eV - red LED's (GaAs)
2.3.1eV - blue/violet LED's (Diamond) 3.Photoconductivity
a.Activation of electrons from valence band to conduction band b.Increase in carriers increases conductivity
2.7 PRACTICE PROBLEMS
1.Are anisotropic properties important in a material? Can a manufacturing process change whether a material is anisotrpoic?
2.Some materials (such as lead and tin) will recrystalize near room temperature. How does this affect design and manufacturing considerations?
3.A bimetallic cable is made of two types of wire strands. The 1” dia. cable is 40% mild steel, 50% aluminum, and the remainder is empty air. What is the combined stiffness of the cable?
4.The amount of heat generated when working a metal is proportional to the plastic deformation. Show how the work can be found using a stress strain diagram.
5.Describe how the cooling rate of steel affects the phases of metal structures. Why does cooling slowly result in a larger grain structure? What do phase structures contain dissimilar types of material?
6.What components will increase the strength of aluminum?