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In the modern galvanizing line, as soon as the steel strip enters the aluminum-containing zinc bath, two reactions occur at the strip and the liquid-zinc alloy interface: (1) iron rapidly dissolves from the strip surface, raising the iron concentration in the liquid phase at the strip-liquid interface; and (2) aluminum forms a stable aluminum-iron intermetallic compound layer at the strip-coating interface due to its greater affinity toward iron. The main objective of this study is to develop a simple and realistic mathematical model for better understanding of the kinetics of galvanizing reactions at the strip and the liquid-zinc alloy interface. In the present study, a model is proposed to simulate the effect of various process parameters on iron dissolution in the bath, as well as, aluminum-rich inhibition layer formation at the substrate-coating interface. The transient-temperature profile of the immersed strip is predicted based on conductive and convective heat-transfer mechanisms. The inhibition-layer thickness at the substrate-coating interface is predicted by assuming the cooling path of the immersed strip consists of a series of isothermal holds of infinitesimal time-step. The influence of galvanizing reaction is assessed by considering nucleation and growth mechanisms at each hold time, which is used to estimate the total effect of the immersion time on the formation mechanism of the inhibition layer. The irondissolution model is developed based on well established principles of diffusion taking into consideration the area fraction covered by the intermetallic on the strip surface during formation of the inhibition layer. The model can be effectively used to monitor the dross formation in the bath by optimizing the process parameters. Theoretical predictions are compared with the findings of other researchers. Simulated results are in good agreement with the theoretical and experimental observation carried out by other investigators.

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Silver nanowires show enhancement in desired properties, due to high surface area and high aspect ratio, which increases the possibility in design and development of many advanced optoelectronic devices. The organization of silver atoms and the morphology of cylindrical nanowire highly influence the desired properties at various physical conditions during applications. Therefore, the synthesis of nanowires with desired atomic organization becomes essential. In the present study, a pseudo-1D morphology of silver nanowires, encapsulated into a Single Wall Carbon Nanotubes (SWCNTs), has been investigated by employing Molecular Dynamics (MD) simulation. At high temperature (T = 1500 K), molten silver encapsulated into a SWCNT attaining a low energy state followed by restricted thermal motion or vibration. With an increase in SWCNT diameter, various unique pseudo-1D morphologies of encapsulated silver atoms were observed during cooling from 1500 to 10 K. Silver atoms, encapsulated into a SWCNT having a diameter of 10.85 Å, mainly reveal 5-fold symmetrical icosahedral (ico) having pseudo-1D morphology. With a further increase in diameter (d = 40.68 Å) of SWCNT, a decagonal pattern consisting of face centered cubic (fcc), hexagonal closed packed (hcp) and body centered cubic (bcc) was evolved due to nonhomogenous packing of silver atoms into SWCNT. Simulation results indicate that the diameter of SWCNT is the one of the major factors controlling the pseudo-1D morphology of silver nanowire. The present theoretical investigations provide a guideline and enhance the current understanding related to solid state physical phenomena of metal nanowires synthesis.

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