Materials Science and Engineering Finals

Materials Science and Engineering Finals

• Corrosion: Destructive electrochemical attack on metals.
• Oxidation: Loss of electrons from a metal atom.
• Reduction: Gain of electrons by a species.
• Galvanic Couple: Two metals connected in an electrolyte causing corrosion.
• Reference Electrode: Used to compare metal half-cells.
• Standard Hydrogen Electrode: Reference electrode using hydrogen gas at 1 atm.
• Electrode Potential: Voltage indicating a tendency to oxidize or reduce.
• Electrochemical Mechanism: Processes governing oxidation and reduction reactions.
• Corrosion Prevention: Strategies to mitigate material degradation.
• Metal Oxidation Rate: Speed at which metals corrode in environments.
• Corrosion Penetration Rate (CPR): Rate of material loss due to corrosion in units of mpy or mm/yr.
• Nernst Equation: Calculates cell potential considering concentration and temperature.
• EMF Series: Ranks metals by their electromotive force.
• Galvanic Series: Ranks metals by reactivity in seawater.
• Current Density: Current per unit area affecting corrosion rate.
• Overvoltage: Displacement of electrode potential from equilibrium.
• Spontaneity of Reaction: Reaction occurs if the overall potential difference is positive.
• Active Polarization: High Hz concentration near electrode, no diffusion limit.
• Destructive Attack: Unintentional damage to metals.
• Corrosion Rates: Measurement of how quickly materials degrade.
• Electrodeposition: Process where metal ions are reduced and deposited.
• Half-Cell Potentials: Indicate equilibrium conditions, not actual corrosion rates.
• Reactivity: Tendency of metals to undergo oxidation.
• Weight Loss: Material loss measured over time due to corrosion.
• Surface Area: Exposed area of a material affecting corrosion.
• Electrochemical Reactions: Reactions involving the transfer of electrons.
• Faraday Constant: 96,500 C/mol, relates charge to moles of electrons.
• Concentration Polarization: Diffusion of Hz ions limits the reaction rate.
• Passivity: Metals become inert due to protective oxide film.
• Uniform Corrosion: Electrochemical corrosion occurs uniformly on surfaces.
• Galvanic Corrosion: Corrosion occurs between electrically coupled dissimilar metals.
• Pitting Corrosion: Localized corrosion forms small pits or holes.
• Crevice Corrosion: Localized corrosion in stagnant areas with lower ion concentrations.
• Intergranular Corrosion: Corrosion along grain boundaries of alloys.
• Selective Leaching: One element is preferentially removed from solid solution alloys.
• Erosion-Corrosion: Corrosion from chemical attack and mechanical abrasion.
• Stress Corrosion Cracking: Cracking due to tensile stress and a corrosive environment.
• Hydrogen Embrittlement: Reduction in ductility from atomic hydrogen penetration.
• Cathodic Protection: Prevention technique converting metal into a cathode.
• Galvanic Protection: Using sacrificial anode to protect metal.
• Impressed Current: External DC source supplies electrons for protection.
• Pilling-Bedworth Ratio: Determines the protective nature of oxide film.
• P-B Ratio < 1: Porous oxide film, unprotective
• P-B Ratio = 1: Stable and protective oxide film.
• P-B Ratio > 1: Dense and protective oxide film.

Ceramic Materials

• Ozone-induced Chain Scission: Ozone reacts with double bonds, causing degradation.
• Weathering: Degradation of materials due to outdoor exposure.
• Thermal Degradation: Degradation of materials due to elevated temperatures.
• Water Absorption: Indicates susceptibility to deterioration from water.
• Thermal Stability: Resistance to degradation from thermal effects.
• Environmental Effects: Factors influencing corrosion rates include temperature, fluid velocity, and concentration.
• Corrosive Concentration: Higher concentration can increase or decrease corrosion.
• Ferrous Metals: Metals containing iron, prone to corrosion.
• Non-Ferrous Metals: Metals without iron, resistant to rust.

Advanced Ceramics and Materials

• Ageing: Enhances yield strength through particle distribution.
• Stress Relieving: Reduces internal stresses.
• Tempering: Reduces brittleness in quenched steel.
• Case Hardening: Surface hardening.
• Carburizing: Increases carbon content on steel surface.
• Cyaniding: Hardening low carbon steel in cyanide bath.
• Nitriding: Hardening by diffusing nitrogen into steel.
• Traditional Ceramics: Includes earthenware, stoneware, and porcelain.
• Polarization: Change in potential due to current flow
• Sintering: Combining ceramic parts together to fuse them.
• Glaze: Finely ground glass coating on ceramics
• Cement Systems: Materials used in construction, can be ceramic-based.
• Electrode Potentials: Measures voltage for half reactions.
• Bioceramics: Materials for medical applications.
• Ceramic Bonding: Spontaneously form bonds between non-metals.
• Covalent Bonding: Sharing of electron pairs.
• Ionic Bonding: Electrostatic attraction between ions.
• Metallic Bonding: Bonds with free-moving electrons.
• Ionic Crystals: Close-packed structure of anions with cations
• Cations: Positively charged metallic ions.
• Anions: Negatively charged nonmetallic ions
• Corrosion Rate:Rate of material loss due to corrosion
• Weight Loss Formula:W=ÁAxKxt
• Coordination Number: Number of surrounding atoms or ions.
• Protective Oxide Film: Thin layer that reduces metal reactivity.
• Electrochemical Corrosion: Corrosion involving the transfer of electrons.
• Grain Boundary Corrosion: Corrosion along the boundaries of grains.
• Sensitization: Heating stainless steel leading to susceptibility to corrosion.
• Diffusion Limitation: Mass transport limits reaction rates.
• Activation Energy: Energy needed to initiate a reaction

Polymers and Metals

• Thermosetting Polymer: Polymers that cannot be remolded after curing.
• Oxide Film: Protective layer for metals from further corrosion.
• Sacrificial Anode: More reactive metal protecting less reactive metal.
• Hydrogen Embrittlement: Reduction in ductility from hydrogen penetration.
• Crosslinked Polymers: Polymers with chains joined by covalent bonds.
• Branched Polymers: Polymers with side chains.
• Linear Polymers: Polymers with straight chain structures.
• Mechanical Properties: Characteristics like strength, ductility, wear resistance.
• Ozone: Accelerates degradation of vulcanized rubbers.
• Thermoplastics: Soft materials shaped by heat (polyethylene, polystyrene, PET).
• Thermosets (Plastics): Materials with covalent compounds preventing softening (e.g vulcanized rubbers).
• Random Copolymer: Two units dispersed in the polymer chain..
• Alternating Copolymer: Two units alternate in the chain.
• Block Copolymer: Identical units clustered along the polymer chain.
• Graft Copolymer: Homopolymer branches grafted onto another polymer.
• Polymer Crystallinity: Ordered packing of molecular chains.
• Semicrystalline Polymers: Crystalline and amorphous regions.
• Lamellae: Thin platelets formed by polymer single crystals.
• Spherulites: Polymer structures equivalent to grains.
• Stress-Strain Behavior: How polymers respond to stress and strain.
• Viscoelastic Deformation: Intermediate behavior between elasticity and viscosity.
• Relaxation Modulus: Time-dependent modulus of elasticity.
• Fracture Strength: Relative strength compared to other materials.
• Crazing: Localized deformation regions.
• Elastic Deformation: Material elongation under stress followed by returning to its original shape.
• Crystallization: Transformation into an ordered structure from a liquid phase.
• Melting: Transformation of a solid into a liquid phase.
• Polymer Types: Categorization of different polymer structures.
• Polymerization: Synthesis of polymers (addition or condensation).

Additional Topics (from the provided pages)

• Pilling-Bedworth Ratio: Determines protective nature of oxide film
• Ionic Character: Percentage of ionic bonding
• Metal Alloys: General properties and types
• Corrosion Mechanisms
• Mechanical Abrasion: Surface damage from friction
• Chemical Agents: Environmental corrosive agents
• Forming Operations (Forging, Rolling, Extrusion, Casting): Metal shaping processes
• Molecular Weight: Average mass of polymer chains

Test your knowledge on essential concepts in Materials Science and Engineering with this comprehensive quiz. Covering topics like corrosion, oxidation, and electrochemical mechanisms, this quiz will challenge your understanding of material degradation and prevention strategies.