Mechanical properties of matter Flashcards
(14 cards)
What is the definition of tensile stress?
The tension force per unit cross-sectional area of a material.
What is the definition of tensile strain?
The extension per unit length of a material.
What is the definition of Young Modulus?
The tensile stress per unit tensile strain.
What is the limit of proportionality?
The value of the stress beyond which the stress is no longer proportional to the strain.
What is the elastic limit?
The value of stress or force beyond which elastic deformation becomes plastic deformation; the material will not return to its original shape and size when the stress or force is removed.
What is represented by the region between the Limit of Proportionality and the Elastic Limit?
Stress is no longer proportional to strain but still elastic.
What is the yield point
The point beyond which the material extends rapidly for a small change in stress. Marks the start of permanent deformation.
What is the Ultimate Tensile Strength?
This is the maximum stress that a material can withstand when being stretched before it breaks.
What is the definition of brittle?
A material which does not exhibit none or much plastic deformation even when subject to a large stress
What is the definition of ductile?
Materials that have a large plastic region and therefore they can be drawn into a wire as it can be stretched or pulled into a long thin shape like a wire. Without snapping.
What is the definition of polymeric?
Materials that consist of long molecular chains; they experience a high strain before breaking
What is the definition of strength?
The extent to which a material resists breaking under stress; a strong material has a high Ultimate Tensile Strength and high breaking stress.
What is the definition of Tough?
Toughness is the ability of a material to absorb energy and plastically deform without fracturing. It’s represented by the area under the stress–strain graph up to the point of fracture — the more area, the tougher the material.
What is the definition of Hardness?
Hardness is the ability of a material to resist plastic deformation, especially scratching, indentation, or cutting.
