| Electromagnetic confinement & shaping for molten metals is an advanced process developed recently. In which the metal is melted to some superheating degree without crucible by induction heat and liquid metal is confined and shaped to desired form by the electromagnetic force at the same time. The parts obtained by it are in perfect surface, refining microstructure and no or less contamination and are with better mechanical properties. The paper will do research on electromagnetic confinement & shaping for circular unequal cross section sample and rectangular cross section sample with large ratio (>3.5) of long side to short side. And the metal is studied that has large specific gravity and high melting point such as stainless steel and superalloy.The study of electromagnetic characteristic indicates that intensity of induction heat and electromagnetic force on the metal are correlative to frequency of current, physical property of sample processed and form and size of sample processed, and distributing of axial magnetic field in the inductor is interrelated with inductor structure, inside wall obliquity, parameter H/D, current density, location of screen etc. According to the result above, shaping inductor and heating inductor are designed for sample processed.The study of distributing of axial temperature in the inductor shows that the factor affecting temperature includes inductor structure, current through inductor, position of screen, speed of shaping sample and heating power of heating inductor in dual frequency shaping. In which, inductor structure, position of screen, speed of shaping sample and heating power of heating inductor in dual frequency shaping influence not only magnitude of temperature but also the position of temperature peak value, and current through inductor influences only magnitude of temperature. Research on course of electromagnetic confinement and shaping for metal with high melting point and large specific gravity shows that above melting point the change of current through inductor influences weight of molten metal far morethan electromagnetic force, and weight of molten metal correlate closely to temperature. So when frequency of power, structure of inductor and position of screen are all appropriate, control or adjust of temperature is key to stability of molten metal, the factors affecting temperature also work on stability of moltea metal. In the unequal section electromagnetic shaping, it will bring about disturbance to molten metal that change of momentum and kinetic energy and redistribution of molten metal due to difference of velocity, which will weaken stability of molten metal. The result was obtained that as the ratio of shaping sample section area to feeding sample section area and speed of shaping sample increase, disturbance strengthen and stability of molten metal will become worse in the unequal section electromagnetic confinement and shaping.It is taken into account factors of both thermal stability and disturbance at the same time that ratio should be little as possible as it can and speed should be moderate in the unequal section electromagnetic shaping.In the electromagnetic shaping for plate with large ratio of long side to short side, magnetic field intensity strengthen in the corner of inductor, surface tension become larger on the corner of molten metal, sample cannot melt completely and temperature of molten metal is uneven because of larger length of long side. So the inductor should be carefully designed and position of sample should be suited in order that experiment has succeed.Some cylindrical stainless steel samples were acquired in several speed and various ratio by means of unequal section electromagnetic shaping, and some rectangular stainless steel and superalloy samples with larger ratio of long side to short side were gained by means of usual electromagnetic shaping.
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