Fe基非晶/纳米晶粉末的放电等离子烧结及磁性能

研究了SPS温度对球磨熔体快淬Fe₇₀Cr₈Mo₂Si₅B₁₅粉末以及MA Fe_73.5Cu₁Nb₃Si_{13 5}B₉ 和Fe₈₀C_o4Nb₇B₉纳米晶粉末的烧结块体合金组织结构与磁性能的影响.结果表明: (1)在30MPa/5min条件下,块体合金相对密度随着烧结温度的升高而增加,当烧结温度为1000℃时,Fe₇₀Cr₈Mo₂Si₅B₁5合金相对密度已达99%以上,当烧结温度进一步升高至1050℃后, Fe_73.5Cu1Nb₃Si1_3.5B₉和Fe₈₀Co₄Nb₇B₉合金相对密度也达到99%;(2)烧结块体合金的主要组成相为α-Fe相,尚存在少量的第二相金属间化合物,这些块体合金α—Fe相的晶粒尺寸均处于纳米级范围内,以Fe₇₀Cr₈Mo₂Si₅B₁₅块体合金的晶粒尺寸为最小,其平均晶粒尺寸约50nm; (3)随着烧结温度的升高,这些块体合金的饱和磁感应强度B_s增大,矫顽力H_c随之降低,以Fe₇₀Cr₈Mo₂Si₅B₁₅块体合金的矫顽力H_c(4.1kA·m^-1)最低.

SPS Sintering and Magnetic Properties of Fe-based Amorphous/Nanocrystalline Powder

The influence of SPS sintering temperature on microstructure and magnetic properties of the sintering bulk alloy of melt quenching Fe₇₀Cr₈Mo₂Si₅B₁₅ powders by ball milling and MA Fe_73.5Cu₁Nb₃Si_13.5B₉ and Fe₈₀Co₄Nb₇B₉ nanocrystalline powders was studied. The results show that (1) under 30MPa/5min conditions, the relative densities of bulk alloys increase with the increase of sintering temperatures. When Fe₇₀Cr₈Mo₂Si₅B₁₅ bulk alloy sintered at 1000℃, its relative density reaches above 99%, and when Fe_73.5Cu₁Nb₃Si_13.5B₉ and Fe₈₀Co₄Nb₇B₉ bulk alloys sintered at 1050℃, their relative densities reach to 99%; (2) the main phase of sintering bulk alloys is α-Fe phase, and a little second phase intermetallic compound. The grain size of α-Fe phase in bulk alloys is in nanometer range, Fe₇₀Cr₈Mo₂Si₅B₁₅ bulk alloy has the finest grain size, its average grain size is about 50nm; (3) with the sintering temperature increasing, the specific saturate magnetization B_s of these bulk alloys increases and coercive force H_c decreases, respectively. Fe₇₀Cr₈Mo₂Si₅B₁₅ bulk alloy has the lowest H_c, 4.1kA·m^-1.