STRUCTURE AND PROPERTIES OF UNDERCOOLED LIQUID-METALS

Electromagnetic levitation is a useful tool to process high-temperatur e and highly reactive melts without a container. it provides a pure en vironment and contamination of the melt is reduced to a minimum. With the application of non-contact measurement techniques, structures and properties of pure samples can be investigated. One major advantage of this approach is that it allows one access to the metastable state of the undercooled melt. This paper reports on measurements of thermophy sical properties of undercooled liquid metals and recent investigation s of their structure. We have performed measurements of the surface te nsion, electrical conductivity, density and thermal expansion of a num ber of pure metals and alloys. Some experiments were performed under m icrogravity conditions which reduce the strength of the required elect romagnetic fields by orders of magnitude and lead to a much higher pre cision. We have recently used electromagnetic levitation in combinatio n with synchrotron radiation to obtain EXAFS spectra of an undercooled Co-Pd alloy.