Transverse compression behavior of polyamide 6.6 rovings: Experimental study

The purpose of the present work is to understand physical phenomena occurring in roving structures under transverse compression. In order to reach this aim, transverse behavior of prototype rovings featuring a small number of polyamide 6.6 filaments are studied using an experimental device developed in our laboratory. Moreover, the effect of roving characteristics on their transverse compression behavior is examined. The studied characteristics are filament diameter and number, roving twist and tension. It is found that the roving behavior under compression shows plateaus separated by a significant increase of compression force, indicating discontinuous changes in the roving structures. This fact may be attributed to a reorganization of rovings followed by a local slippage between filaments. Transverse properties of rovings are affected by contact-friction inter filaments and the initial filament section fraction. In fact, it is more difficult to compact high-twisted rovings. Rovings with a greater number of filaments require a higher force in order to be compacted. The pre-tension of the rovings has no noticeable effect on their compression behavior.