Synthesis and Characterization of Polymer Nanocomposites Containing Fe- 40 at.% Si Powder Particles Prepared by High Energy Ball Mill

Abstract

Fe‒Si alloys are widely used as transformer magnets and magnetic cores because of their excellent soft magnetic properties. Fe60Si40 powders were milled in a high energy planetary ball mill (Rctsch PM400) under argon atmosphere at different time of milling. The metal powders obtained have an average diameter d50 of 2.5 to 6 um. The introduction of Si into Fe can result in a decrease of magnetic anisotropy (therefore leading to a decrease of coercivity). The nanocomposite magnetic cores were made from the Fe60Si40 powder obtained by high energy ball milling for different milling time. The particles of powder were mixed with unsaturated polyester (UP) to obtain toroidal cores. The polymerization process was made under a magnetic field H-500 Am. and ensured a preferential orientation of powder particles. Influences of the metallic powder fraction on soft magnetic properties as well as thermal increase under isothermal conditions were investigated along with the possibility to control these properties with the size and amount of powder fraction. It was also found that the soft magnetic properties of the polymer composites can be controlled in a wide range and depends on the mass fraction of the metallic powder Fe60Si40 in the composite, on shape and size of the powder particles and their orientation in the composite.

Improved Mechanical Properties of Alumina Ceramics Using Plasma-Assisted Milling Technique

“…Therefore, the reactivity of the powder is enhanced after ball milling [ 12 ]. This mechanical activation effect of high-energy ball milling is extremely favorable for reducing the subsequent reaction conditions of a powder, and its activation effect and subsequent reaction mode have been extensively studied [ 13 , 14 ]. However, the efficiency of the high-energy ball milling method is low, which leads to long ball milling times and pollution caused by ball milling.…”

“…However, the efficiency of the high-energy ball milling method is low, which leads to long ball milling times and pollution caused by ball milling. Meanwhile, it is difficult to achieve accurate control of material structures and the synthesis of some compounds [ 14 ].…”