The dies are subject to alternatingstresses due to loading and unloading during the deformation process and this causes crack initiation and eventual failure.
在变形加工过程中，由于加载、减载、模具承受交变应力作用，这就将引起开裂并发生重大破坏。
2
As a new compactor, oscillatory roller makes rearrangement of material particles in a dense way with a mechanism of rapidly alternating shear stresses.