MECH 2060 Exam 1 ACTUAL UPDATED
QUESTIONS AND CORRECT ANSWERS
Body Centered Cubic (BCC) - CORRECT ANSWERS✅✅A common crystal structure
found in some elemental metals. Within a cubic unit cell, atoms are located at the corners and
center of the cube.
Face Centered Cubic (FCC) - CORRECT ANSWERS✅✅A crystal structure found in some
common elemental metals. Within a cubic unit cell, atoms are located at the corners and
centers of each face.
Hexagonal Close-Packed (HCP) - CORRECT ANSWERS✅✅A crystal structure found for
some metals. The HCP unit cell is of hexagonal geometry with a triangle in the middle, and is
generated by the stacking of close-packed planes of atoms.
Alloying - CORRECT ANSWERS✅✅Technique involving the mixing of two or more
metals to create a new material, e.g. the fusion of copper and tin to make bronze.
Allotropism - CORRECT ANSWERS✅✅the existence of an element in two or more distinct
forms. Examples: Oxygen as O, O2 and O3; Carbon as coal, graphite and diamond.
Elastic deformation - CORRECT ANSWERS✅✅Temporary change in shape or volume
from which a material rebounds after the stress is removed
Plastic Deformation - CORRECT ANSWERS✅✅Permanent deformation caused by strain
when stress exceeds a certain value
Shear Stress - CORRECT ANSWERS✅✅Stress that occurs when forces act in parallel but
opposite directions, pushing parts of a solid in opposite directions
Critical Shear Stress - CORRECT ANSWERS✅✅The value at which an object begins to
deform when subjected to forces acting in parallel and opposite directions.
Shear stress equation - CORRECT ANSWERS✅✅Fs/As
, applied shear force/ sheared area =
Twinning Plane - CORRECT ANSWERS✅✅When critical shear stress is applied to a
material, the material deforms and moves in opposite directions along this feature. This
feature ought to bisect the atoms in a material diagonally.
Slip Plane - CORRECT ANSWERS✅✅When critical shear stress is applied to a material,
the material splits and moves in opposite directions along this feature. This feature ought to
bisect the atoms in a material at a right angle.
Slip System - CORRECT ANSWERS✅✅The combination of a slip plane and a slip
direction. Metals with 5 or more of these are generally considered ductile.
Body Centered Cubic (Slip Systems) - CORRECT ANSWERS✅✅This crystal structure has
48 slip systems, which generally indicates good strength and moderate ductility, with higher
ductility at elevated temperatures.
Face Centered Cubic (Slip Systems) - CORRECT ANSWERS✅✅This crystal structure has
12 slip systems, which indicates moderate strength and good ductlility.
Hexagonal Close-Packed (Slip Systems) - CORRECT ANSWERS✅✅This crystal structure
has 3 slip systems, with more systems active at high temperatures. Metals in this group are
generally brittle at room temperature.
Point Defect - CORRECT ANSWERS✅✅A flaw in the structure of a material that occurs at
a single site in the crystal lattice, such as vacancies, substitutions, and interstitial defects.
Vacancy - CORRECT ANSWERS✅✅A point defect in a metal that happens when there's a
gap in the lattice arrangement.
Interstitial Atom - CORRECT ANSWERS✅✅A point defect in a metal that happens when
there's an extra atom in the lattice arrangement.
QUESTIONS AND CORRECT ANSWERS
Body Centered Cubic (BCC) - CORRECT ANSWERS✅✅A common crystal structure
found in some elemental metals. Within a cubic unit cell, atoms are located at the corners and
center of the cube.
Face Centered Cubic (FCC) - CORRECT ANSWERS✅✅A crystal structure found in some
common elemental metals. Within a cubic unit cell, atoms are located at the corners and
centers of each face.
Hexagonal Close-Packed (HCP) - CORRECT ANSWERS✅✅A crystal structure found for
some metals. The HCP unit cell is of hexagonal geometry with a triangle in the middle, and is
generated by the stacking of close-packed planes of atoms.
Alloying - CORRECT ANSWERS✅✅Technique involving the mixing of two or more
metals to create a new material, e.g. the fusion of copper and tin to make bronze.
Allotropism - CORRECT ANSWERS✅✅the existence of an element in two or more distinct
forms. Examples: Oxygen as O, O2 and O3; Carbon as coal, graphite and diamond.
Elastic deformation - CORRECT ANSWERS✅✅Temporary change in shape or volume
from which a material rebounds after the stress is removed
Plastic Deformation - CORRECT ANSWERS✅✅Permanent deformation caused by strain
when stress exceeds a certain value
Shear Stress - CORRECT ANSWERS✅✅Stress that occurs when forces act in parallel but
opposite directions, pushing parts of a solid in opposite directions
Critical Shear Stress - CORRECT ANSWERS✅✅The value at which an object begins to
deform when subjected to forces acting in parallel and opposite directions.
Shear stress equation - CORRECT ANSWERS✅✅Fs/As
, applied shear force/ sheared area =
Twinning Plane - CORRECT ANSWERS✅✅When critical shear stress is applied to a
material, the material deforms and moves in opposite directions along this feature. This
feature ought to bisect the atoms in a material diagonally.
Slip Plane - CORRECT ANSWERS✅✅When critical shear stress is applied to a material,
the material splits and moves in opposite directions along this feature. This feature ought to
bisect the atoms in a material at a right angle.
Slip System - CORRECT ANSWERS✅✅The combination of a slip plane and a slip
direction. Metals with 5 or more of these are generally considered ductile.
Body Centered Cubic (Slip Systems) - CORRECT ANSWERS✅✅This crystal structure has
48 slip systems, which generally indicates good strength and moderate ductility, with higher
ductility at elevated temperatures.
Face Centered Cubic (Slip Systems) - CORRECT ANSWERS✅✅This crystal structure has
12 slip systems, which indicates moderate strength and good ductlility.
Hexagonal Close-Packed (Slip Systems) - CORRECT ANSWERS✅✅This crystal structure
has 3 slip systems, with more systems active at high temperatures. Metals in this group are
generally brittle at room temperature.
Point Defect - CORRECT ANSWERS✅✅A flaw in the structure of a material that occurs at
a single site in the crystal lattice, such as vacancies, substitutions, and interstitial defects.
Vacancy - CORRECT ANSWERS✅✅A point defect in a metal that happens when there's a
gap in the lattice arrangement.
Interstitial Atom - CORRECT ANSWERS✅✅A point defect in a metal that happens when
there's an extra atom in the lattice arrangement.
