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The Sn-10.2 Sb (mass fraction) peritectic alloy was prepared using a vacuum melting furnace and a hot filling furnace. The samples were directionally solidified upwards at steady state conditions with a constant temperature gradient (G=4.5±0.2 K. mm -1 ) under different growth velocities (V=13.3-266.7 µm. s -1 ) in a Bridgman-type directional solidification apparatus. The effects of the growth velocity (V) on the dendritic spacings were investigated. Primary dendrite arm spacing (PDAS) of α phase in directionally solidified Sn-10.2 Sb peritectic alloy was measured on the longitudinal and transverse sections of 4 mm diameter cylindrical samples. Secondary dendrite arm spacing (SDAS) was measured on the longitudinal section. The experimental results show that the measured PDAS (λ 1L , λ 1T ) and SDAS (λ 2 ) decrease with increasing growth velocity. The dependence of PDAS, SDAS, microhardness (HV) and compressive strength (σ c ) on the growth velocity were determined by using a linear regression analysis. The experimental results were compared with the previous experimental results and the results of the experimental models.

Metallized yarns have become an integral part of fashion because they give extra sheen to garments and an inimitable appearance to fabrics, making them special yarns. However, because of repetitive washing and abrasions, the metallic part of the yarn in the fabric is removed and the fabric loses its brightness and becomes transparent. This study aims to solve this issue by searching for high-quality metallized yarn production methods to eliminate problems during usage. In the experimental part of the study, eight different types of metallized films were produced using the lamination technique with two kinds of adhesives. Non-laminated metallized polyester films were used as a reference to understand the effectiveness of the lamination process. Metallized yarns were produced from laminated metallized films by using standard production parameters. After producing nine different types of metallized yarns, monotype knitted fabrics were then from these yarns. Yarn’s basic properties and fabric’s mechanical properties were then measured to compare the effect of the thin film type, lamination process and adhesive type effect on these properties. The test results showed that the lamination technique significantly improves the resistance of the repetitive washing process and the abrasion property of fabrics. The best results were obtained with polypropylene thin films. However, they had a higher friction coefficient and a harder handle property than polyester films. When using a thinner polypropylene film, this problem could be eliminated, and the yarns could be an important alternative choice for commercially producing metallized yarns in the future.

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