Surface tension and viscosity of liquid and undercooled tantalum measured by a containerless method

摘要

Electrostatic levitation and multibeam radiative heating overcame contamination and sample position stability problems associated with handling of liquid tantalum. This approach allowed the measurements of the surface tension and the viscosity of the superheated and undercooled states of tantalum using the oscillation drop method. The measurements of the surface tension could be expressed as σ(T) = 2.15X 10~3-0.21(T-T_m) mN m~(-1) over the 2970-3400 K interval, where T_m is the melting temperature (3290 K). The value at T_m agrees well with the scarce data appearing in the literature. Similarly, on the 3000-3400 K temperature range, the viscosity was determined as η(T)=0.0035 exp[213.3/(RT)](mPa s).