The term "yield point" refers to the stress level at which a material begins to deform plastically. The spelling of this word is comprised of two syllables - "yield" and "point". The first syllable, "yield," is pronounced as "/jiːld/" which starts with a /j/ sound followed by a long /i/ sound and ends with a /ld/ sound. The second syllable, "point," is pronounced as "/pɔɪnt/" which starts with a /p/ sound, followed by a diphthong /ɔɪ/ sound and ends with a /nt/ sound.
The term "yield point" refers to a specific characteristic of materials, particularly solids or fluids, which describes the point at which they exhibit a change in behavior under applied stress or force. The yield point represents the stress or force threshold at which a material starts to deform permanently, also known as yielding, instead of returning to its original form after the stress is removed.
In materials like metals, the yield point is reached when the stress applied causes the atomic lattices to rearrange, resulting in plastic deformation. At this point, the material undergoes a significant change in shape or structure that is not reversible, leading to a permanent alteration. This differs from the elastic deformation that occurs below the yield point, where the material can return to its original shape once the stress is released.
For fluids, such as fluids with high viscosity, the yield point refers to the minimum force or stress required to initiate flow. Below the yield point, the fluid behaves like a solid, resisting any applied stress. However, once the yield point is surpassed, the material starts to flow and exhibit liquid-like behavior.
The determination of the yield point is essential in engineering and material science, as it helps to identify the maximum stress a material can handle without undergoing permanent deformation or failure. It facilitates the understanding of the behavior of materials under different conditions, enabling engineers to design and construct structures and machines that can withstand various loads and stress levels.
The word "yield point" originated from the combination of two separate terms: "yield" and "point".
1. Yield: The term "yield" has its roots in Middle English and Old English. It originally came from the Old English word "gieldan", which means "to pay, give, or offer". Over time, the meaning evolved to include the idea of "surrender" or "submit". In the context of materials science and mechanics, the term "yield" refers to the point at which a material undergoes significant deformation without any further increase in stress. It usually signifies the beginning of plastic deformation.
2. Point: The word "point" comes from the Latin word "punctus", which means "a prick or dot". It has been used in various contexts to denote a specific place, time, or stage.