Anisotropic Compressive Properties and Energy Absorption Efficiency of Porous Twisted Short Fiber Materials

摘要

Novel stainless steel porous twisted short fiber materials (PTSFMs) with spatial composite intertexture structure are produced by compaction following with sintering of twisted short fibers. The stainless steel twisted short fibers are fabricated using a cutting stainless steel fiber ropes method with a self-developed rotary multi-cutter tool. The porous structure of the stainless steel PTSFMs exhibits a large difference in the through-thickness and in-plane direction, which results in differences in compressive behavior. During the compressive process, it is determined that the stainless steel PTSFMs exhibit typical elastic-plastic behaviors (three deformation stages) in the in-plane direction, but in the through-thickness direction, entered the compact densification zone after short-term nonlinear elastic deformation without a plastic platform stage. The compression deformation resistance in the through-thickness direction is obviously stronger than that in the in-plane direction at a given porosity. The compression strength and the anisotropy both decreased with increased porosity. The compression properties are anisotropic, which also result in different energy absorption efficiencies of the two directions. The relationship between the porosity and the energy absorption efficiency is not monotonically increasing or decreasing, but with the change of porosities, there is an optimal porosity, which has relatively high-energy absorption efficiency.