Investigation of Viscosity Measurements of Molten Fe-Si-B-Nb Alloys

摘要

The properties of Iron-based metallic glasses, such as glass-forming ability and soft magnetic properties, (MGs) have been widely investigated. However, seldom reports are available concerning the properties of these iron-based melts. In the present work, the viscosity of superheated Fe-Si-B-Nb metallic glass forming liquids (MGFLs) was measured by a torsional oscillating viscometer. It has been found that the crucial condition to get viscosity data using graphite crucibles is to reach a superheated degree of at least 250 K for melts prior to measurements. The viscosity increases monotonically with a decrease in temperature before solidification, without distinct changes of dynamic mechanism during cooling. The present work indicates that these iron-based melts are heterogeneous even above the liquidus temperature. This finding helps to understand the melts of iron-based MGs and to improve the production process of iron-based glass ribbons.