As the material is deformed beyond the strain that elastic deformation persists, the stress is no longer proportional to strain, and permanent, nonrecoverable, or plastic deformation occurs.
As the material is deformed beyond the strain that elastic deformation persists, the stress is no longer proportional to strain, and permanent, nonrecoverable, or plastic deformation occurs.
当材料的形变超出弹性形变发生的范围，其应力将不再与应变成正比，永久的、不可回复的形变发生，即为塑性形变。