Experimental simulation of friction and wear between carbon fiber tow and heddle eye under periodic tension during the <scp>3D</scp> weaving process

Abstract Weaving is the predominant technology for fabricating carbon fiber composite preforms. Carbon fibers are subjected to various forms of reciprocating friction in the weaving process. Especially, the friction between carbon tow and heddle eyes is difficult to describe due to the complex conditions of variable tension. In this study, a novel experimental simulator was developed to characterize the friction behavior between warp yarn and heddle eye under periodic tension variation. The friction force (F f ) and coefficient of friction (COF) under variable tension conditions were tested. To investigate the variation of real contact area between carbon tow and heddle eyes under variable tension conditions, a silicon‐film indentation method was developed, and the effect of pre‐tension on carbon tow was obtained by combining three‐dimensional micro surface morphology and Hertz analysis methods. The results indicated that both the COF and F f decreased with increasing pre‐tension. 3D morphology analysis suggested that the tow contact area reached its maximum when the pre‐tension was 1.2 N. In the Hertzian calculation of the actual contact area, the change of the contact area and the pre‐tension was generated by taking into account the evolving contact length, which differed from the measured friction force value by a constant factor. Highlights A variable tension device was designed and developed. The friction between carbon tow and heddle eye was simulated under variable tension. The F f and COF under different pre‐tensions were tested. A silicon‐film indentation method was proposed. The relationship between contact area and friction was studied.