Surface tension and viscosity of the Ni-based superalloy CMSX-4 measured by the oscillating drop method in parabolic flight experiments

The surface tension and viscosity of the Ni-based superalloy CMSX-4 was investigated by the oscillating drop method. The surface tension and viscosity of CMSX-4 specimen were measured under reduced gravity conditions on a parabolic flight with different oxygen content. Specimen containing low and high oxygen content were obtained by using additional Ti-gettering during remelting. The oxygen content of specimen prepared for parabolic flight experiments were determined by the LECO hot gas extraction method. A reduction in the value of the slope of the surface tension as function of temperature was observed due to increasing purity of specimen after successive remelting in high-purity atmosphere, while the viscosity of low oxygen content specimen was similar to that of MM247LC. Result shows that oxygen content does not affect the surface tension at liquidus temperature, while viscosity of high oxygen content specimen raise by 20% by rise in temperature.