Formation of Fe-Ni Nanoparticle Strands in Macroscopic Polymer Composites: Experiment and Simulation

Abstract

Magnetic-field-induced strand formation of ferromagnetic Fe-Ni nanoparticles in a PMMA-matrix is correlated with the intrinsic material parameters, such as magnetization, particle size, composition, and extrinsic parameters, including magnetic field strength and viscosity. Since various factors can influence strand formation, understanding the composite fabrication process that maintains the strand lengths of Fe-Ni in the generated structures is a fundamental step in predicting the resulting structures. Hence, the critical dimensions of the strands (length, width, spacing, and aspect ratio) are investigated in the experiments and simulated via different intrinsic and extrinsic parameters. Optimal parameters were found by optical microscopy measurements and finite-element simulations using COMSOL for strand formation of Fe50Ni50 nanoparticles. The anisotropic behavior of the aligned strands was successfully characterized through magnetometry measurements. Compared to the unaligned samples, the magnetically aligned strands exhibit enhanced conductivity, increasing the current by a factor of 1000.

Synthesis of orientated Ni0.89Fe0.11/polymer nanofibres with a bimodal nanoparticle size distribution by electrospinning and thermal processing

“…Other reasons include effects such as broken bonds, vacancies, surface strain, and oxidation of the shell that become more important as the nanoparticle size is reduced [55,56]. The measured high field magnetization from other Ni 1-x Fe x nanoparticles with x ranging from 0.1 to 0.25 is also lower than the bulk values [53,54,[57][58][59]. Ni nanorods made by electrospinning also have lower saturation magnetizations that are ~42% of the bulk values [20,60,61].…”

Solvent Influence on the Magnetization and Phase of Fe-Ni Alloy Nanoparticles Generated by Laser Ablation in Liquids

“… M(H) curves of FeNi nanoparticle powders from colloids prepared in different liquids at room temperature (300 K). FeNi in acetone data reproduced from [ 67 ]. …”

Directional Migration and Distribution of Magnetic Microparticles in Polypropylene-Matrix Magnetic Composites Molded by an Injection Molding Assisted by External Magnetic Field

“…The finite element method (FEM) is a widely used numerical technique for solving engineering and physics problems involving behaviors that can be described by differential equations [30]. Because granular fillers were scattered and tiny, finite element analysis software was usually used to simulate the motion of granular fillers.…”