Preparation and properties of glass-coated microwires

Technological aspects of the Taylor–Ulitovsky method for fabricating glass-coated microwires with different structures of metallic nucleus are discussed. The main parameters of the process can be distinguished as follows: a casting rate of microwire and its limits, cooling rate of the metal core, geometrical characteristics and alloy composition. The casting rate is important in determining the upper and lower limits of the diameter of microwire. Depending on the critical quenching rate (104–107 K/s), metastable, amorphous or supersaturated state phases are obtained. Mixed structures consisting of micro- and nanocrystallites embedded into the amorphous matrix can also be formed. During the fabrication process, strong internal stresses are generated, which determine some of the most interesting properties of these materials. In particular, magnetic properties depend mostly on the magnetoelastic anisotropy arising from the coupling of the internal stresses with magnetostriction constant.