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Soft magnetic powdered materials are a specific group of materials of remarkable application potential, and they have been intensively studied by scientists to improve their magnetic properties. The shape, in which are usually these materials prepared (conventional sheets, crystalline ribbon prepared by rapid solidification technology etc.), is in many cases not suitable shape for industry applications. One of the ways to prepare material suitable for industrial applications (3-d material) is the compaction of powder, which can be produced by the mechanical milling of mixture of powders, thin ribbons, sheets, etc. The presented work describes the explanation of the influence of the mechanical milling of iron powder. The material prepared by mechanical milling exhibits excellent soft magnetic properties and they are usually part of the compacted material for different applications. [ABSTRACT FROM AUTHOR]

Soft magnetic materials (SMMs) are widely used in many industries, for example, in conventional transformers (where electric steel is used) as well as cosmology or medicine [1-2]. The elements such Fe, Ni, Co and their alloys can be included into SMMs. Permalloy (Fe-Ni), Supermalloy (Fe-Ni-Mo) and their modifications are widely known [3]. Depending on the way of their preparation they can be divided into two main groups: soft magnetic compacts or soft magnetic composites. Soft magnetic compacts are made by compacting ferromagnetic powder without adding any insulation, so it is conventional soft magnetic material but in the desired shape. Soft magnetic composite materials are progressive materials which are made from ferromagnetic insulated and compacted powder. The aim of this work was the investigation of the possibility for optimalization of magnetic properties of the powdered compacts. Mechanical milling leads to the decrease of powder size elements and on the other hand introduces structural defects of the material strongly negative affected magnetic properties of the compacts. One of the important aspects is determination of optimum conditions for mechanical milling, as ball to powder ratio (BPR) and milling time. By investigation of three samples of pure iron powder particles prepared by different ball to powder ratio has been detected that the most suitable magnetic properties exhibit the sample milled for BPR 9:1. [ABSTRACT FROM AUTHOR]

Soft magnetic compacts and composites are an important group of soft magnetic materials prepared by powder metallurgy methods. Although they have been known to researchers and manufacturers for over a century, emerging new technologies continue to enable their development. The study of the influence of imperfections in the shape of particles has proved that they have a substantial impact on the mechanical properties of the final product. Rough surfaces also present an obstacle to the displacement of domain walls in ferromagnets. This paper describes the effect of the process of mechanical surface treatment of powder particles on the magnetic properties of the resulting compact. The conclusions are based on the study of four samples formed from iron-based powders that have been subjected to a treatment process designed to smooth the surface and reduce impurities. [ABSTRACT FROM AUTHOR]