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Anelasticity: Dependence of Elastic Strain on Both Stress and Time

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Anelasticity: Dependence of Elastic Strain on Both Stress and Time Ramos, Mark Roland T. Anelasticity: Dependence of elastic strain on both stress and time. This can result in a lag of strain behind stress. In materials subjected to cyclic stress, the anelastic effect causes internal damping. Design Stress: A permissible maximum stress to which a machine part or structural member may be subjected, which is large enough to prevent failure in case the loads exceed expected values, or other uncertainties turn out unfavorably. Ductility: In material science, ductility is a solid material's ability to deform under tensile stress; this is often characterized by the material's ability to be stretched into a wire. Elastic Deformation: Reversible alteration of the form or dimensions of a solid body under stress or strain. Elastic Recovery: That fraction of a given deformation of a solid which behaves elastically. Engineering Strain: The change in specimen length divided by the original length. Refer to the definition for strain. Engineering Stress: Load applied to a specimen in a tension or compression test divided by the cross-sectional area of the specimen. The change in cross-sectional area that occurs with increases and decreases in applied load, is disregarded in computing engineering stress. It is also called conventional stress. Hardness: Hardness is the resistance of a material to localized deformation. The term can apply to deformation from indentation, scratching, cutting or bending. In metals, ceramics and most polymers, the deformation considered is plastic deformation of the surface. Modulus of Elasticity: The ratio of the stress applied to a body to the strain that results in the body in response to it. The modulus of elasticity of a material is a measure of its stiffness and for most materials remains constant over a range of stress. Plastic Determatic: Poisson’s Ratio: is the ratio of transverse contraction strain to longitudinal extension strain in the direction of stretching force. Tensile deformation is considered positive and compressive deformation is considered negative. Rendezvous: Proportional Limit: The greatest stress which a material is capable of sustaining without deviation from proportionality of stress and strain (Hooke's Law) or the point on the stress-strain curve at which stress ceases to be proportional to strain. It is expressed in force per unit area, usually pounds per square inch. Safe Stress: Shear: s defined as the component of stress coplanar with a material cross section. Shear stress arises from a force vector perpendicular to the surface normal vector of the cross section. Tensile Strain: The elongation of a material which is subject to tension. Toughness: The ability of a metal to deform plastically and to absorb energy in the process before fracture is termed toughness. The emphasis of this definition should be placed on the ability to absorb energy before fracture. True Strain: Instantaneous % of change in length of specimen in mechanical test. It is equal to the natural logarithm of the ratio of length at any instant to original length. True Stress: Is applied load divided by actual area of the cross section through which load operates. It takes into account the change in cross section that occurs with changing load. Yield Strength: is the amount of stress at which plastic deformation becomes noticeable and significant. Yielding: To give in return for labor expended; to produce, as payment or interest on what is expended or invested; to pay;.
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