Research Topics

Manufacturing Technology and

Process Metallurgy

  • Ironmaking and Steelmaking
  • Continuous Casting
  • Welding
  • Interfacial/ Surface Tension
  • Computational Fluid Dynamics Simulation
  • Application of Magnetohydrodynamics (MHD) in steelmaking
  • Heat and Mass Transfer

 

 


This page is under-development. More research works are being added continuously. 


Recent Research Works

Liquid Metal 3D Printing

The manufacturing industry is moving towards 3D printing technology, especially in the area of semiconductors and electronic. At the same time, liquid metal has emerged as a promising material for flexible electronic circuits and design. This has opened a new dimension for research.

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Capillary Flow in Micro-Channels: Application in Process Metallurgy

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Numerical Modeling of Inclusion Motion Behavior in an AC Flash Butt Welding Process

A numerical investigation has been carried out to study the inclusion particle’s motion behavior (pushing and engulfment) during the flash butt welding process. The solidifying boundary layer plays an important role in determining the fate of inclusion particles. The governing mechanism of inclusion particles movement (near to solidifying boundary layer) under the influence of thermal and concentration gradient has been studied. The inclusion particles are encountered with thermal Marangoni force in the thermal boundary layer which pushes particles away from the solidification front if the Sulphur concentration gradient is lower than a certain limit. However, the particles are pulled when Sulphur concentration gradient is higher than a critical value. Moreover, the applied pushing force on the welding metal also influences the inclusion particle movement. A numerical model based on Computational Fluid Dynamics (CFD) has been developed to analyze the above-mentioned phenomenon. The predicted results obtained from CFD simulations have been found well accord with the experimental results.

Evaluation of Temperature and S Concentration Effect on Interfacial Tension between Molten Microalloyed Steel and Alumina

In order to lower the amount of oxygen in steel during the steelmaking process, deoxidation is carried out by using deoxidizer. Alumina inclusions are formed in molten steel when Aluminum is used as a deoxidizer. These inclusions are generally removed in the refining process, but unremoved inclusions would be left in the steel, resulting in defects in the steel product. Therefore, it is essential to remove the inclusion during the refining or the continuous casting process. Zeze and Mukai [3] suggested a semi-empirical model to determine the capture/wash away behavior of inclusions and bubbles at the solid-liquid interface during solidification. In this study, the interfacial tension between microalloyed steel and alumina was experimentally determined to predict the behavior of alumina inclusions at the solid-liquid interface. In the present work, the surface tension of microalloyed steel was measured using the constrained drop method. The temperature was controlled within the range of 1823 – 1873 K and the concentration of S 11 – 94 ppm. It was found that the surface tension increased with increasing the temperature and decreased with increasing sulfur content. The contact angle between microalloyed steel and alumina was measured using the sessile drop method. Moreover, it was noted that the contact angle decreased with increasing temperature in most experiments. The interfacial tension between molten microalloyed steel and alumina was evaluated using Young’s equation. The surface tension of alumina was taken from the literature. The interfacial tension decreased with increasing temperature in most cases. However, the interfacial tension increased with increasing temperature at 92 ppm of Sulphur. The wash-away velocity of pushing/engulfment of alumina inclusions at the solid-liquid interface of microalloyed steel was predicted using the derived interfacial tensions in the present study. It was concluded that the inclusions pushing from the solidification interface are more likely to occur as the sulfur concentration decreases when the sulfur concentration is lower than 64 ppm.

CFD simulation of melt and inclusion motion in a mold under the influence of electromagnetic force

The current scenario of steel market is expressively changing. The rapid increase in demand for clean and high-quality steel has changed the way of the conventional steelmaking process. The steelmakers are now looking for new technology and processes which can ensure their competitiveness in the market and reduce the carbon emission. The application of electromagnetic forces is among the various new technologies which have been employed for improving the quality and efficiency. Among them, electromagnetic braking controls the melt flow velocity and further it reduces the free-surface chaotic velocity profile in a continuous casting mold. In present work, a three-dimensional numerical model has been developed to investigate the effect of electromagnetic forces on melt flow characteristics in continuous casting mold. The results obtained from CFD model suggest that melt flow is greatly influenced by the electromagnetic forces. Further, vertical downward velocity component can be obtained by the application of electromagnetic force. In addition to this, inclusion motion behavior has been reported under the influence of an electromagnetic force.

Optimization of flow control devices to minimize the grade mixing in steelmaking tundish

The minimization of grade intermixing in a tundish is one of the import concern of steelmakers. Different design and operating parameters of the tundish, as well as flow control devices (FCDs), has been used in last decade by researchers to modify the flow characteristics of melt in the tundish. In the present work, the three-dimensional numerical investigations have been carried out to optimise the design of FCDs in multi-strand tundish by using response surface methodology. The interaction of design parameters i.e., shroud depth, advanced pouring box (APB) wall angle, dam height and dam position has been studied by the response surface plots. An effort has been made to quantify the impact of APB angle and shroud depth. Moreover, these two FCDs have important implications in future for efficient inclusion removal. The quantification of intermixed grade steel in tundish has been made at each strand. Further, average output from all strand has been analyzed and the optimum design of FCDs has been suggested. An important finding from this study is that some FCDs have an adverse impact on mixing in the far zone of the tundish.