بررسی تا‌خوردگی فرش دست‌باف تحت فشار استاتیکی

To study the way of folding handmade carpets, the selected sample has been put under pressure of 50g/cm2 weight at three different states. The pressure has increased uniformly and continuously at 100,200, 500, 1000 and 1500 g/cm2. The thickness of the carpet has been recorded continuously during the measurement of the thickness of the carpet sample. The pressing parameters of the carpet have been calculated in KES-F system with simulation and fitting of two components model of de-jong pressure. Also, the thickness of the part that is not able to be pressed is estimated. Based on the obtained results, it has been shown that pressing energy in the curved folded part of the carpet is very low, but the pressing energy in the part with two layers of the carpet on each other is very high. Nevertheless, the percentage of elasticity in two layers of the carpet placed on each other is remarkably low. It shows that the sensitivity and flexibility of this area is more in comparison with two layers of the carpet. On the other hand, the thickness of the part that is not able to be pressed in the area with two layers of the carpet on each other is more than that of the investigated areas. In this way, the pressing is carried out by piercing the upper naps on the lower ones. Without folding and flatting of the carpet, it is not pressed and just upper layer naps are pressed on the lower layers. In this study, the phenomenon of Domino folding is used to describe the folding behavior of the handmade carpet under static pressing