Magnetic properties of fully dense Sm2Fe17Nx magnets prepared by shock compression

Explosive shock processing of Pr2Fe14B/α–Fe exchange-coupled nanocomposite bulk magnets

“…Considerable work has been performed in characterizing the microstructural and magnetic properties of explosively compacted single-phase RFeB 9,14 and SmFeN alloys. 15 Preparation of bulk Nd 2 Fe 14 B/Fe 3 B nanocomposite magnets by dynamic compaction (using a propellant gun facility) has also been reported by Saito. 12 However, the compact had low coercivity (H c ∼ 215 kA/m) and its density was only approximately 85% of the ingot density. Recently, we investigated the shock consolidation of Pr 2 Fe 14 B/␣-Fe nanocomposite powders using a 3-capsule plate-impact gas gun recovery fixture with shock loading conditions and capsule geometry designed based on two-dimensional computer simulations of shock wave propagation characteristics.…”

Explosive consolidation of Sm–Fe–N and Sm–Fe–N/(Ni, Co) magnetic powders

“…However, a slight shift in the peak toward higher diffraction angle can be observed. The peak shift, according to Mashimo et al [5], was due to the decrease in the percentage of nitrogen in the consolidated specimen.…”

“…Fabrication of fully dense Sm 2 Fe 17 N x bulk materials was attempted by Mashimo et al [5] using shock compression recovery experiments with a propellant gun and explosives, but the sound compacts were not obtained by explosive consolidation.…”

Magnetic properties of anisotropic Sm–Fe–N bulk magnets produced by spark plasma sintering method

“…Till now, Sm-Fe-N bulk magnets have been produced by non-conventional consolidation techniques such as shock compaction or compression-shearing method [8][9][10]. Sm-Fe-N bulk magnets with porosities of 2-10% have been realized by optimizing the experimental conditions [8,9]. There has been no practical application of these techniques, however, due to the difficulties involved.…”

“…However, this sintering technique cannot be applied to the production of Sm-Fe-N bulk magnets because Sm 2 Fe 17 N 3 intermetallic compound is not stable at high temperatures and decomposes into the a-Fe and SmN phases above 873 K [4]. Till now, Sm-Fe-N bulk magnets have been produced by non-conventional consolidation techniques such as shock compaction or compression-shearing method [8][9][10]. Sm-Fe-N bulk magnets with porosities of 2-10% have been realized by optimizing the experimental conditions [8,9].…”