Atomic transport in Zr_(41.2)Ti_(13.8)Cu_(12.5)Ni_(10)Be_(22.5) and Zr_(46.8)Ti_(8.2)Cu_(7.5)Ni_(10)Be_(27.5) melts has been investigated with incoherent, quasielastic neutron scattering. From the q dependence of the quasielastic signal an average self-diffusion coefficient of the incoherent scatterers Ni and Ti has been obtained. Values are on a 10~(-10) m~(2) s~(-1) scale. In contrast to the viscosity, the diffusion coefficient is rather independent of the alloy's composition. Above the liquidus temperature times scales for Ni and Ti self diffusion and for viscous flow differ by up to two orders of magnitude: It appears, that the smaller atoms diffuse in a relative immobile Zr matrix.
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