Materials Science and Engineering - Vocabulary Flashcards

Vocabulary flashcards to assist in the study of Materials Science and Engineering concepts.

Composition

The chemical make-up of a material, including elements and quantities.

Structure/Microstructure

How materials are shaped into useful components affecting their properties.

Synthesis and Processing

How materials are made from naturally occurring or man-made chemicals.

Properties

Performance characteristics of materials, including cost.

Metals and Alloys

Materials known for good electrical and thermal conductivity, high strength, and formability.

Ceramics

Inorganic nonmetallic materials primarily resistant to high temperatures.

Polymers

Typically organic materials that are plastics, known for lower strength but higher strength-to-weight ratio.

Composite Materials

Materials formed from two or more constituents to combine strengths.

Semiconductors

Materials with electrical conductivity between ceramics and metals.

Covalent Bonding

Atoms share valence electrons, resulting in directional bonds.

Metallic Bonding

Atoms donate electrons to form a 'sea' of electrons, leading to high electrical and thermal conductivity.

Ionic Bonding

Electrostatic attraction between positive and negative ions formed from the donation or acceptance of electrons.

Van der Waals Bonding

Weak secondary bonds resulting from dipole moments in atoms or molecules.

Burgers Vector

Magnitude and direction associated with a dislocation in materials.

Modulus of Elasticity (E)

Measure of a material's ability to stretch for a given force per area.

Coefficient of Thermal Expansion (CTE)

Fractional change in a material's dimension per degree of temperature change.

Crystalline Structure

Atoms arranged in a periodic fashion.

Amorphous Structure

Atomic arrangement with no long-range order.

Yield Strength

Stress at which plastic deformation begins.

Tensile Strength

Maximum stress material can withstand before deformation.

Ductility

Ability of a material to be permanently deformed without breaking.

Fatigue

Failure due to crack propagation under repetitive loading.

Fracture Toughness

Ability of a material with flaws to withstand applied stress without failing.

Strain Hardening

Increase in strength due to dislocation interactions during plastic deformation.

Recrystallization

Process that eliminates dislocations and restores ductility in materials post cold-working.

Creep

Time-dependent permanent deformation under constant stress at elevated temperatures.

Elastic Deformation

Reversible stretching of a material under stress.

Plastic Deformation

Permanent change in shape of a material due to stress.

Thermosetting Polymer

Polymers that become rigid and do not soften on reheating due to cross-linking.

Thermoplastic Polymer

Polymers that become soft when heated and can be molded.

Elastomers

Polymers characterized by large elastic deformations under stress.

Fiber-Reinforced Composite

Composite that includes fibers to enhance strength.

Particulate Composite

Composite with dispersed particles to enhance certain properties.

Matrix

Continuous phase in composite materials.

Dispersed Phase

Embedding phase within the matrix of composite materials.

Temperature Dependence of Strength

Strength of materials often decreases with increased temperature.

Notch Sensitivity

Tendency of a material to fail from notches or cracks.

Slip System

Combination of slip planes and directions in crystal structure where dislocations move.

Impact Toughness

Ability of a material to absorb energy during fracture.

Intergranular Fracture

Cracks that propagate along grain boundaries.

Transgranular Fracture

Cracks that propagate through the grains of material.

Microstructure

Structure of a material at the microscopic level, governing many properties.

Hydrogen Bonding

Type of van der Waals bonding where hydrogen is part of a polar bond.

Electrical Conductivity

Ability of a material to conduct electric current.

Thermal Conductivity

Ability of a material to conduct heat.

Reactivity

Tendency of a material to undergo chemical reaction.

Brittle Material

Material that fractures without significant plastic deformation.

Alloy

Metal combined with other elements to enhance properties.

Young's Modulus

Another term for the modulus of elasticity.

Ductile-to-Brittle Transition Temperature (DBTT)

Temperature below which materials typically fail in a brittle manner.

Slip Plane

Plane along which dislocation motion occurs.

Slip Direction

Direction along which dislocations move in a crystal lattice.

Fracture Mechanics

Study of the propagation of cracks in materials.

Critical Stress Intensity Factor (Kc)

Stress intensity above which a crack will propagate.

Cubic Unit Cell

Smallest repeating unit of a crystal structure.

Imperfections

Defects in a crystal structure, affecting material properties.

Diffusion

Movement of atoms or molecules through a material.

Thermal Stress

Stress induced in a material due to temperature changes.

Hardness Test

Measure of a material's resistance to indentation or scratching.

Strain Rate

Change in strain over time, influencing material behavior.

Porosity

Presence of pores within a material, affecting strength.

Inclusion

Unwanted particles or phases embedded within a material.

Matrix Strength

Strength of the continuous phase in a composite.

Cross-Linked Polymer

Polymer chains linked together to improve mechanical properties.

Thermal Treatment

Process of heating and cooling materials to alter their properties.

Mechanical Properties

Characteristics that describe the reaction of a material to applied forces.

Wear Resistance

Ability of a material to resist surface wear.

Corrosion Resistance

Ability of a material to withstand degradation in corrosive environments.

Cryogenic Treatment

Process of treating materials at very low temperatures to improve properties.

Hot Workability

Ability of a material to be shaped without losing strength at high temperatures.

Auxetic Material

Materials that expand laterally when stretched, possessing a negative Poisson's ratio.

Nano-materials

Materials with structures at the nanoscale, often exhibiting unique properties.

Biodegradable Polymeric Material

Polymers capable of being broken down by microorganisms.

Interfacial Bonding

Bonding occurring at the interface between different materials in composites.

Shape Memory Alloys

Alloys that can return to a predetermined shape when heated.

Thermal Activation

Influence of temperature on the processing and behavior of materials.

Critical Flaw Size

Flaw size that can lead to catastrophic failure under stress.

Endurance Limit

Stress level below which a material can withstand repeated loading indefinitely.

'H' Petch Relationship

Relationship describing how grain size affects yield strength in polycrystalline materials.

Metal Matrix Composite (MMC)

Composite consisting of a metal matrix with additional materials to enhance properties.

Plastic Deformation

Permanent change in shape resulting from stress exceeding the yield strength.