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This article studies about the mechanical strength of different functionalized Carbon nanotubes (CNTs) reinforced Polyethylene (PE) fiber composite fabricated by melt spinning. There are four types of CNTs used, which are called as produced, carboxylated, octadecylated, polymer wrapped CNTs. Influence of mechanical drawing (melt spinning) on the mechanical strength of fibers is measured by direct comparison with mechanical strength of bulk type functionalized CNTs polymer composites, which fabricated using hot press. Dispersion and interfacial bonding strength/adhesion of CNTs with PE matrix are investigated through fracture surfaces image analysis. Functionalized CNTs composites show a significant improvement of mechanical strength of pure polymer than non functionalized CNTs polymer composite. Whereas polymer wrapped CNTs polymer composite give the highest mechanical strength in this study. Mechanical strength of bulk composites are significantly increased after mechanical drawing process indicates that melts spinning may influence on the crystallization of polymer. Fracture surface analysis revealed that additional functionalized CNTs enhanced dispersion and interfacial bonding with polymer matrix.

Magnetic properties and crystal structure of melt spun SmCo_7-xM_x (M = Hf, V, Nb, and Ta; x = 0–0.3) ribbons have been investigated. The experimental results showed that not just Hf but also V, Nb and Ta prefer to occupy 2e site in the TbCu₇ structure and remarkably increase coercivity of the ribbons from 1.7 kOe for x = 0 to 10–12 kOe for x = 0.2, which would be due to the increase of magnetic anisotropy field by the element substitution. Furthermore, the effect of C addition on the magnetic properties and microstructure of melt spun Sm(Co, M)₇ ribbons were also studied. A small amount of C addition in the ribbons could effectively refine their microstructure, and leads to further improvement of the magnetic properties. The optimal magnetic properties of B_r = 6.9 kG, _iH_c = 11.8 kOe and (BH)_max = 10.6 MGOe were attained for SmCo_6.8Hf_0.2C_0.12 nanocomposites.

Direct difference methods have been used to solve the simultaneous non-linear partial differential equations for melt spinning without recourse to linearisation or perturbation approximation. The stability of each difference schemes was studied by error analysis using the Taylor series, and by comparison of the results obtained from numerical simulation with the logical value in melt spinning. It is found that computation with 19 digit long double precision has significantly simplified the stability problem of difference equations. Using this method, the precise critical draw ratio of draw resonance in an isothermal and uniform tension spinning of Newtonian fluids can be obtained in between 20.218 and 21.219, a figure consistent with 20.218 which was obtained by a linear perturbation approximation method by Kase and Denn. It thus has paved the way to computation of full information for unsteady melt spinning processes using the difference method.

A direct difference method has been developed for Non-Newtonian power law fluids to solve the simultaneous non-linear partial differential equations of melt spinning, and to determine the critical draw ratio for draw resonance. The results show that for shear thin fluids, the logarithm of the critical draw ratio has a well defined linear relationship with the power index for isothermal and uniform tension melt spinning. When the power index approaches zero, the critical draw ratio points at unity, indicating no melt spinning can be processed stably for such fluids. For shear thick fluids, the critical draw ratio increases in a more rapid way with increasing the power index.

(Zr,Hf)NiSn-based half-Heusler thermoelectric materials have been prepared by melt spinning and spark plasma sintering to refine the grain size. The grain sizes of the melt-spun thin ribbons varied from ~500 nm to ~3 μm and no significant grain growth were found for the bulk samples compacted by spark plasma sintering. Nanoscale precipitates dispersed in the matrix were observed, which should be more metallic due to the increase of the electrical conductivity. The reduction of lattice thermal conductivity was observed due to the refined grain sizes.

A series of Ni_50-xFe_xMn₃₄Al₁₆(0 ≦ x ≦ 18) and Ni₃₈Fe_12-zCo_zMn₃₄Al₁₆(3 ≦ z ≦ 6) ribbons were prepared by the melt-spinning method. With Fe substitution for Ni in Ni₅₀Mn₃₄Al₁₆ ribbons, the magnetization of the austenitic phase increases greatly while that of the martensitic phase increases little. Thus, in the magnetic field of 5 T a large magnetization change (22 Am²/kg) during the martensitic transformation is observed in Ni₃₈Fe₁₂Mn₃₄Al₁₆ ribbon. The effect of Fe substitution for Ni on the magnetic modulation was investigated, which is attributed to the change of the magnetic interaction between Mn–Mn atoms. By substituting Co for Fe in Ni₃₈Fe₁₂Mn₃₄Al₁₆ ribbons, a magnetic-field-induced martensite-austenite transformation is observed in Ni₃₈Fe₉Co₃Mn₃₄Al₁₆ ribbon.

In this work, the thermoelectric (TE) performance of $P$-type SnTe based on melt spinning (MS) technology is comprehensively researched. Elements of Sb and Bi are introduced to significantly improve the electrical transport properties. Along with the fine grains, SnTe-based ribbons can be obtained in a short time by MS method. It indicates that the MS technology improves the sample preparation efficiency and reduces the lattice thermal conductivity. The melt-spun one reveals that the lowest lattice thermal conductivity of Sn${}_{0.83}$Sb${}_{0.16}$Bi${}_{0.01}$Te is 0.87 W m${}^{-1}$K${}^{-1}$at 323 K. To optimize the ZT (where $Z$ is the figure of merit and $T$ is Kelvin temperature) of SnTe, Sb and Bi are codoped in SnTe matrix, as a result of the enhancement of the power factor (PF) value and decreasing the thermal conductivity and electronic thermal conductivity simultaneously. Finally, the highest ZT of 1.01 at 823 K and an average ZT of 0.57 is obtained over a broad temperature range from 323 K to 823 K in Sn${}_{0.83}$Sb${}_{0.16}$Bi${}_{0.01}$Te. It is worth noting that the remarkable improvement on the TE performance of pristine SnTe sample is achieved, with the highest ZT of 0.55 at 823 K and an average ZT of 0.18. It shows the potential for following research on the performance of lead-free SnTe-based TE materials.