Mechanics of compaction of a porous non-woven fiber solid

Abstract

Abstract A porous non-woven material system is investigated where glass fibers bonded by a polymeric binder phase. This work contributes a micromechanics perspective to the understanding of the long-term stability of thermal insulation materials. The non-woven is considered as a soft and compliant material system, and the study focuses on the influence of the binder phase on the mechanical response of the overall non-woven material. Cyclic compression experiments demonstrate the relationship of the modulus of the binder to the modulus and the degradation rate in cyclic loading. A micromechanics model is established based on CT images. Computations demonstrate the formation of force chains and fiber–fiber contact during compression. Stresses are highest in fibers possessing curvature. After the occurrence of fiber fracture the compressive response is more compliant even if a larger material volume is recruited to participate in load transfer. Such stress redistribution overall lowers the stress level and reduces the subsequent material degradation rate.