What is the yield point of a material?

The yield point of a material is the stage where it begins to deform plastically. When a load is applied to a material, it will initially deform elastically, meaning that once the load is removed, it will return to its original dimensions. However, once the load reaches the yield point, the material undergoes plastic deformation, which is non-reversible; it will not return to its original size and shape after the load is removed.

At the yield point, the material can suddenly yield to the load, which means it can start to deform significantly with little or no increase in the applied load. This is a critical concept in materials science and engineering because understanding the yield point helps engineers determine the limits for safe applications and ensure that materials perform as expected under stress.

Other options do not accurately define the yield point. The breaking point refers to the failure of the material, which occurs after the yield point has been surpassed. The maximum load applied does not specifically indicate yielding, as it could occur without plastic deformation. Elastic recovery refers to the material returning to its original shape before exceeding the yield point and does not pertain directly to yielding.