**3. Comparison of yarn and fabric properties (non-destructive versus theoretical and classical standards)**

This section will provide an understanding of the cotton-made yarn and fabric properties and how realistic the nondestructive measurements from the XRMCT images are.

The yarn and fabric characteristics obtained from the classical test standards are displayed in **Table 2**. In addition, **Figures 7** and **8** depict the comparison between theoretical calculation and experimental measurements obtained from CT images and classical test standards.

**Yarn Diameter**: Results showed that both the theoretical warp and weft yarn diameters [calculated from Eq. (1)] were statistically different (*P*-value <0.05) than the respective CT yarn diameters (**Figure 7a**). Irrespective of weave design, the calculated theoretical diameters were constant for the same count yarn as well as for both warp and weft yarns. Experimental CT measurements showed that the same count yarns resulted in different diameters of the warp and weft yarns in both plain and satin woven fabrics. Diameter in 40Ne yarns was higher than 60Ne yarns. In addition, given the same yarn count, higher yarn diameters were observed in satin fabrics than the plain-woven fabrics [12, 13].

Different weave designs and thread densities attributed to the distortion of the yarns as they interlaced with each other during weaving. Such distortion resulted in the differences in the warp and weft yarn diameters which can be understood from **Figure 9**.

Plain woven fabrics contained high number of interlacements. In contrast, satin fabrics had more floats or weft yarns which allowed more freedom to the yarns to move around and resulted in larger yarn diameters (**Figure 9**). The authors suggested that the CT images were capable of providing more realistic yarn diameters in the fabrics than the theoretical values [12, 13].

**Yarn Packing Factor**: **Figure 7b** shows that the different diameter yarns obtained from the CT measurements resulted in a variation in the yarn packing factors while the theoretical yarn packing factor was constant (0.6 for ring-spun yarns). Given the same yarn count, an increase in yarn diameter decreases the yarn packing factor which was not reflected from the theoretical values but from the CT measurements [12, 13].

**Yarn Crimp**: Yarn crimp% obtained from ASTM D3883 (option A) test method (**Table 2**) and CT method were compared (**Figure 7c**). For both warp and weft yarns, results from a two-sample t-test at 95% confidence interval showed that the measurements from the two methods were not statistically different (*P*-value of 0.43 and a higher *R*<sup>2</sup> ). Given the same yarn count and weave design, a further analysis of the CT data showed that warp crimp% was significantly higher than the weft crimp% (*P*value <0.05). In addition, yarns in the plain-woven fabrics exhibited higher crimp% than the satin fabrics. The ASTM method of yarn crimp measurement involved extraction of yarns while the CT method was nondestructive. Therefore, the CT method can be reliably used to measure yarn crimp without compromising the structure [12, 13].

**Fabric Thickness**: Fabric thicknesses obtained from ASTM D1777–96(2002) method and CT method were compared. Results depicted in **Table 2** and **Figure 8a** suggested that the measurements from the two methods were not statistically different (*P*-value 0.21, and *R*<sup>2</sup> = 0.97). It was also observed that the satin fabrics exhibited higher thickness than the plain-woven fabrics. In the satin fabrics, the presence of more floats or weft yarns which extended across multiple yarns (**Figure 9**) attributed to overriding of yarns and looser fabric construction, and therefore, greater fabric volume and thickness than the plain-woven fabrics. In addition, 60Ne yarn-made satin fabrics had lower thickness than the 40Ne yarn-made fabrics. The smaller diameter 60Ne yarns contained higher twists (TPI) which compressed the fibers and increased yarn tightness (**Table 2**), and therefore, attributed to lower fabric thickness.


