The effects of manufacturing parameters in the planar flow casting process on the ribbon formation and the puddle stability of Fe 78 Si 9 B 13 alloy are investigated experimentally. The ribbon morphology, surface quality, and puddle geometry are examined at different conditions and the transient evolution processes of puddle for molten metal passing through a rectangular nozzle are observed. The successful operability window for the production of Fe 78 Si 9 B 13 ribbon is established and it is found the scope is different from that of Al-based alloy. The trend lines of the alloys on the plane of Reynolds number versus Weber number corresponding to obtain a successful ribbon are established. The ribbon thickness is found to vary with the applied pressure across the crucible and the wheel speed to the power of 0.45 and − 0.9, respectively. The formation of small air pockets could be enhanced by increasing the applied pressure difference and wheel speed, or by decreasing the nozzle-wheel gap and the jetting temperature.

Axisymmetric compression tests using Gleeble 3800 simulator were carried out to investigate hot deformation behaviors of an AA5083 alloy under high strain rate conditions. Sharp temperature rise and load cell ringing characterized by severely vibrational load responses were encountered at strain rates higher than 20 s-1 and sample buckling occurred at low temperatures. The load cell ringing was corrected using a moving average method with a two-way filtering operation to correct phase distortion. Isothermal flow curves were obtained by fitting the instantaneous temperatures into a binomial function, while buckling was correlated with sample height and Young’s modulus. After the corrections, hyperbolic sine equation was successfully used to extend from the hot tensile data having strain rates lower than 3 s-1 to 100 s-1. Quantitative analyses were accordingly made over the effects of temperature, strain rate and work hardening behavior on the flow curves. The previous constitutive equation in form of temperature, strain and strain rate was modified to predict the hot deformation resistance of the AA5083 alloy at temperatures of 250-450oC under the high strain rate operations.

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The purpose of this study is to measure contact angle and surface tension of liquid Fe-Si-B alloys at high temperature using sessile drop method. The surface tension and contact angle result is based on sessile drop method by use of a digital camera to take the drop profile and fit the profile by Youngs-Laplace equation. The surface tension of liquid Fe-Si-B alloy and its dependence on temperature has been studied. Contact angles of this liquid alloy on various refractories substrate have been determined using this instrument. The result showed that the contact angles and surface tension of Fe-4Si-3B alloy liquid drop on Al2O3 substrate have value of 134 to 127and 1575-1350 mN/m respectively. The result indicated also that increasing temperature can decrease contact angle and surface tension in Fe-Si-B alloy.