Induction heating is a non-contact-based energy source that has the potential to quickly melt the metal and become the alternate energy source that can be used for additive manufacturing. At present, induction heating is widely used in various industrial applications such as melting, preheating, heat treatment, welding, and brazing. The potential of this source has not been explored in the additive manufacturing domain. However, the use of induction heating in additive manufacturing could lead to low-cost part fabrication as compared to other energy sources such as laser or electron beam. Therefore, this study explores the feasibility of this energy source in additive manufacturing for fabricating parts of metallic materials. An experimental system has been developed by modifying an existing delta three-dimensional printer. An induction heater coil has been incorporated to extruder head for semi-solid processing of the metal alloy. In order to test the viability of the developed system, aluminium material in the filament form has been processed. Obtained results have shown that the induction heating–based energy source is capable of processing metallic materials having a melting point up to 1000° C. The continuous extrusion of the material has been achieved by controlling the extruder temperature using a proportional integral derivative–based controller and k-type thermocouple. The study also discusses various issues and challenges that occurred during the melting of metal wi

Abstract The radial Si distrinution in Fe-3wt%Si crystals grown by floating zone melting with induction heating differes remarkably from that with electron beam heating. From the radial Si distribution we have deduced the main features of the flow pattern in the molten zone for both heating methods. Marangoni convection was shown to be dominant in the case of electron beam heating. With induction heating the flow direction was found to be inverted in comparison with electron beam heating. The change of the flow direction is explained by the action of electrodynamic forces driving the melt convection in the opposite direction from that driven by Marangoni forces.

An electromagnetic levitation apparatus incorporating an electron beam for auxiliary heating and melting has been developed for experiments on containerless vacuum purification and undercooled solidification of high melting materials. Stable levitation of 10-g specimens of molten tungsten has been achieved and a variety of containerless solidification experiments is being performed, including pure polycrystalline castings and single tungsten crystals grown from the undercooled levitated melts.

The paper presents a survey of the industrial applications of electric heating from an electrical engineering view-point. The different electrical heating processes possible are described including direct and indirect resistance, induction and dielectric heating plasma, laser- and electron-beam processes for such processes as heat treatment, drying, melting metals and plastics, chemical processing and electric reduction. The range and operating characteristics of each process are described and related to their applications.

A self-rectifying electron beam melting technique is described. Utilizing an ac power supply, in contrast to the more usual dc supply, the in situ self-rectifying approach offers a simple and very inexpensive means of producing metallic pendant drops for use in containerless melt-processing experiments.