for metals, the elastic limit is defined as the 0.2% offset yield strength. This represents the stress at which the stress-strain curve for uniaxial tensile loading deviates by a strain of 0.2% from the linear-elastic line. It is the same in tension and compression. It is the stress at which dislocations move large distance through the crystals of the metal. Elastic limit depends on the mode of loading. For modes of loading other than uniaxial tension, such as shear and multiaxial loading, the strength is related to that in simple tension by a yield function. For metals, the Von Mises yield function works well. The Tresca function is sometimes more convenient, because it is less complicated.
Indication of maximum stress that can be developed in a material with-out causing plastic deformation. It is the stress at which a material exhibits a specified permanent deformation and is a practical approximation of elastic limit. Offset yield strength is determined from a stress-strain diagram. It is the stress corresponding to the intersection of the stress-strain curve, and a line parallel to its straight line portion offset by a specified strain. Offset for metals is usually specified as 0.2%, i.e., the intersection of the offset line and the 0-stress axis is at 0.2% strain. Offset for plastics is usually 2%.
Is the maximum stress that can be applied without permanent deformation of the member. The symbol Fy is used to denote this stress.
The minimum stress at which a material will start to physically deform without further increase in load. NEC conductor type designation for conductors with ETFE insulation for use in dry locations.
The lowest stress at which a material undergoes plastic deformation. Below this stress the plastic is elastic; above it , viscous.
The limiting stress beyond which a material will sustain permanent deformation.
Stress in psi at which a specimen assumes a specified limited permanent set. yoke: [1] A triangular metal piece used to connect the main brake cable with the stirrup cable in a centerpull brake system. Also known as a " saddle" or "pick-up." [2] A bracket or coupling. [3] A forked parts of a U-joint connected by the spider.
The load in pounds per square inch where the material under test begins to change dimensions and will not completely recover when the load is removed. Yield strength will normally be lower than ultimate strength. Generally speaking, the more rigid a material is, the closer will be yield and ultimate strengths. Furthermore, the more resilient a material is, the greater the spread between yield and ultimate strengths.
the stress required to produce a very slight yet specified amount of plastic strain.
The stress under load at which the proportionality between stress and strain in a tensile specimen is no longer equal. From this point on the specimen elongates at a reduces stress level with the increasing load until rupture occurs.
The stress beyond which stainless steel undergoes important permanent flow — commonly specified as that stress producing a 0.2% offset from the linear portion of the stress-strain curve.
the stress at which a plastic material exhibits a specified limiting permanent set.
The end of the linear elastic region for most metals. The yield strength is the highest stress a structure can endure without permanent deformation.
The stress at which general plastic elongation of the test piece takes place. This point is well defined in hardened and tempered or annealed structures but can be ill defined in "as drawn" structures.
measurement that describes the force a metal product bears at a pre-defined % of deviation in dimensional proportions. The specified deviation for titanium is usually at 2(two) %.
The indication of maximum stress that can be developed in a material without causing plastic deformation.
The stress at which a material exhibits a specified deviation from proportionality of stress and strain. An onset of 0.2% is used for many metals.
The specified minimum yield strength or yield point of reinforcement in psi.
A measure of the amount of mechanical stress a material can withstand before it permanently deforms.
