Materials Flashcards
What is the definition of a brittle material?
A material that does not show plastic deformation and deforms very little under high stress.
Define breaking strength.
The stress value at the point of fracture/breaking.
What is a ductile material?
A material, which can undergo large plastic deformation under tensile stress. A material that can be easily made onto wires.
Define elastic deformation.
A reversible change in the shape of an object due to a compressive or
tensile force. Removal of stress or force will return the object to its original shape and size.
Define elastic limit.
The value of stress (or force) beyond which plastic
deformation occurs, and the material or object will no longer return to its original shape and size when
the stress (or force) is removed
Define elastic potential energy.
The energy stored in an object because of its deformation.
State Hooke’s law.
The force applied is directly proportional to the extension of the spring unless the
limit of proportionality is exceeded.
Define limit of proportionality.
The value of stress or force beyond which stress is no longer directly
proportional to strain.
Define plastic deformation.
An irreversible change in the shape of an object due to a compressive or
tensile force — removal of the stress or force produces permanent deformation.
Define polymeric.
Description of a material comprising of long-chain molecules, such as rubber, which
may show large strains.
Define a strong material.
A material with a high ultimate tensile strength.
Define tensile strain.
The extension per unit length of a material.
Define tensile stress.
The force per unit cross-sectional area on a material.
Define ultimate tensile strength.
The maximum stress that a material can withstand before it breaks.
Define yield point.
A point on a stress–strain graph beyond which the deformation is no longer entirely
elastic.
