Materials and Alloys Lecture Review

Flashcards covering various materials, their properties, metallic crystal structures, imperfections, alloys, and fabrication methods.

Density

A comparison of density at room temperature for various materials.

Elastic Modulus

A comparison of stiffness at room temperature for various materials.

Strength

A comparison of tensile strength at room temperature for various materials.

Resistance to Fracture

A comparison of fracture toughness at room temperature for various materials.

Metals and Alloys

Composed of one or more metallic elements and often nonmetallic elements in relatively small amounts; relatively stiff and strong, ductile, and resistant to fracture.

Face-Centred Cubic (FCC)

A metallic crystal structure found in metals such as copper, aluminum, silver, and gold.

Body-Centred Cubic (BCC)

A metallic crystal structure found in metals such as chromium, iron, tungsten, and molybdenum.

Hexagonal Close-Packed (HCP)

A metallic crystal structure found in metals such as cadmium, magnesium, titanium, and zinc.

Dislocations

Line defects in crystalline metals around which some of the atoms are misaligned.

Interfacial Defects

Boundaries that have two dimensions and normally separate regions of the materials that have different crystal structures and/or crystallographic orientations.

Ferrous Alloys

Alloys in which iron is the principal constituent, including steels and cast irons.

Nonferrous Alloys

Alloys that are not iron based.

Steels

Iron-carbon alloys that may contain appreciable concentrations of other alloying elements, with carbon content normally less than 1.0 wt%.

Cast Iron

Iron-based alloys with carbon contents above 2.14 wt%.

Forging

A method for metal fabrication involving shaping metal using localized compressive forces. These forces are delivered with a hammer or die.

Rolling

A method for metal fabrication where metal stock is passed through one or more pairs of rolls to reduce the thickness, to increase the length, and to produce a uniform thickness.

Extrusion

A method for metal fabrication where a metal billet is forced through a die of the desired cross-section. It can be done hot or cold.

Drawing

A method for metal fabrication used to reduce the cross-section of a wire or bar by pulling it through a die. This process can increase the length and modify the shape.

Additive Manufacturing

A method for metal fabrication, including direct energy deposition and powder bed fusion process, where materials are joined to make objects from 3D model data, usually layer upon layer.