Professor Albert0 Barella passed a \~* a j 011 hfmdi 30, 2001. This paper is dedicated to Iiis rneniory. ABSTRACTThe abrasion resistance of different wool and blended fabrics is measured with the Martindale wear and abrasion tester, the abrasion kinetics is identified by the shape of the mass loss curve versus abrasion cycles up to yam breakage. A concave kinetic curve shows a low initial weight loss rate, which continues to increase throughout the process up to the end. A convex kinetic curve begins with a high initial weight loss rate, which continues to decrease throughout the process. The third kinetic curve shows an almost linear relationship between mass loss and abrasion cycles up to yarn breakage. Due to the long time required for the abrasion test to yarn breakage, a simplified method is used based on the determination of mass loss up to 5000 abrasion cycles. The initial mass loss rate and the mean value of this rate throughout the 5000 abrasion cycles (ix., the mean abrasion gradient) seem to be good estimates of the surface and structural abrasion degradation of the fabrics, and they show a strong relationship with the structural parameters of the fabrics.Fabric rubbing, scraping, and wearing against itself or against other abrasive surfaces produces abrasion in wear. As expected, abrasion first modifies the fabric surface and then affects the internal structure of the fabric, damaging it. Abrasion resistance can be measured according to different criteria. Probably the most widely used is the number of cycles until fabric breakage or a hole occurs, but it can also be measured by the weight loss of the fabric after a given number of abrasion cycles. Another accepted method is to determine the strength loss caused by a selected number of abrasion cycles or, more properly, a graph of abrasion cycles versus strength loss.Abrasion in wear is not easy to define, given the variations existing between wearers. Such variability should therefore be borne in mind when establishing a correlation between wearers and abrasion. Thus, some wearers can "wear out" a "good" fabric in a 100 hours, whereas other users will not wear out a "poor" fabric, even after 1000 hours. In accordance with the ASTM Standards, there are three methods based on different measuring principles: the rotary platform [3], the flexing trial [4] and abrasion over an inflated membrane [5]. The British Standards use the Martindale wear and abrasion tester [ 6 ] , and abrasion resistance can be measured according to two different principles. The first corresponds to the number of cycles needed to produce yarn breakage, and the second one is based on a calculation of the average rate of mass loss of the fabric. This methodology is based on a determination of the number of cycles needed to break two yarns by abfasion, and then the mass loss is measured in three stages of approximately 25,50, and 75% of the number of cycles needed to break the yarns. A graph of mass loss as a function of the number

We have studied the elastic recovery and inverse relaxation phenomena of polyester staple fiber rotor spun yarns. Better fiber orientation obtained with a drawing passage before spinning results in higher permanent deformation and lower delayed elastic recovery of the yarn. Yarn twist has little influence on elastic characteristics. The stress produced in the yarn when strained at 10% is higher when fibers are straighter and lower when twist increases. The inverse relaxation effect increases with the level of orientation of the fibers in the yarn.

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During finishing, internal stresses stored during spinning, warping and weaving are removed and fabrics attain an almost fully relaxed state. Their handle feels warm and smooth. Table I lists the finishing operations of the four finishing treatments considered in this study, which are those normally employed by the European industry. Washing removes fiber ends from the surface and fibers are sometimes brought to it. Milling, mainly applied to fabrics containing wool, is a vigorous mechanical process designed to bust yarns and develop fullness in carded fabrics. Pure wool fabrics respond more strongly to the milling process than fabrics which contain little or perhaps no wool. Carbonizing removes the cellulosic matter mixed with wool. Raising produces a thin layer of protruding fibers and shearing cuts it to uniform length. Pressing flattens the fibers on the surface and decatizing fixes the fabric containing wool into its pressed condition, improving its handle and appearance. The final pressing removes unintended creases and enhances fabric appearance by increasing their lustre and smoothness.1 Abstract Twenty-three woolen, mixed and worsted woven fabrics made of wool, polyester/ wool, polyester/cellulosic and waste fibers underwent four different finishing treatments. The effect of the finishing on gray goods was studied by comparing the structural parameters and the results obtained by compressive and cyclic multiaxial strain testing. It was observed that finishing lead to a more fully, dimensionally stable and more relaxed fabric structure. By comparing the results obtained from finished fabrics it was possible to distinguish between the different groups of finished fabrics: Pure wool fabrics, non-pure wool fabrics, woolen fabrics made of warp worsted yarns (mixed fabrics) and pure worsted fabrics. The measured structural parameters were fabric density, thickness and mass per square meter, Eurotex and image analysis cover factors, air permeability and sonic velocity. The results given by compressional testing were compressibility, the Onions compressive index and Kawabata's linearity of compression. The results of the cyclic multiaxial strain testing were initial deformation, relaxation and creep indexes and bagginess after five deformation cycles.