Crimp intervals

Consider a warp yarn first, e.g. the first warp yam in Figure 2.2(a). Its level codes are w, = 0,2,4,2. The yarn can be subdivided into crimp intervals, which constitute a part of the yarn between two intersections. At the first crimp interval, the yarn is supported (interacts with at the ends of the interval) with weft yams in the layers (J = 1 and l = 2 (the subscript gives the number of the crimp interval, the superscript identify one of its ends). The yam is situated above its supporting weft at the left end of the crimp interval and below the supporting weft at the right end. 

To constmct the same description for a weft yam, the intersection codes and parameters of crimp intervals of warp are used. Consider a weft yarn i at layer /. First, looking up the lists of crimp interval parameters, find the first warp that has in its lists /j = 1 or... 

I (i.e. supported by the weft yarn i at layer /) This would be the left end of the first crimp interval on the weft yam. The support warp number is thus found, and the position sign of the weft would be inverse to the position sign of the warp. Then find the next warp yam supported by the weft (/,/). This would be the right end of the first crimp interval on the weft yam, and the left end of the second crimp interval. Continue until all the crimp intervals would be defined. Note that in multilayered stmctures the number of crimp intervals on a weft yarn can be smaller than the total number of the warp zones. For example, the first weft yam in the first layer of the weave. Figure 2.2(a) (eight warp zones) has only five crimp intervals, as it does not intersect with three of the Z-yams. 

In practice, sample carriers in the form of loops, coils or simple wires made of different alloys at fixed temperature intervals are used. Ferromagnetic metal foils (Pyrofoil ) are available for 21 different pyrolysis temperatures ranging from 160 °C to 1040 °C (JAI Ltd., Tokyo, Japan). In this case, the sample gets crimped into the metal foil using a dedicated tool before analysis (Oguri and Kirn, 2005). 

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