阅读说明：本技术 一种高丰度稀土Ce/Y/Nd/La取代的高最大磁能积的钐铁氮基磁粉 (High-abundance rare earth Ce/Y/Nd/La substituted samarium-iron-nitrogen-based magnetic powder with high maximum magnetic energy product ) 是由 郑精武 徐健伟 乔梁 车声雷 蔡伟 李涓 李旺昌 应耀 余靓 于 2020-07-09 设计创作，主要内容包括：本发明公开了一种高丰度稀土Ce/Y/Nd/La取代的高最大磁能积的钐铁氮基磁粉。所述的钐铁氮磁粉以分子式所表示的组成成分为：(Sm<Sub>1-x</Sub>,RE<Sub>x</Sub>)<Sub>u</Sub>(Fe<Sub>1-y-z</Sub>,T<Sub>y</Sub>,M<Sub>z</Sub>)<Sub>v</Sub>N<Sub>w</Sub>。式中,RE是稀土元素Ce/Y/Nd/La或Ce/Y/Nd/La与其他稀土元素的组合,0.33≤x≤0.95；本发明钐铁氮基磁粉具有较高的最大磁能积、矫顽力、剩余磁感应强度和高温使用性能。RE添加导致磁粉饱和磁化强度的提高,各向异性下降略有下降,T和M添加可以抑制或抵消RE添加引发磁粉各向异性的下降。RE、T和M是提高磁粉的饱和磁化强度,略微削弱、保持甚至提高磁粉的各向异性,磁粉仍保持高居里温度。(The invention discloses samarium-iron-nitrogen-based magnetic powder with high maximum energy product substituted by high-abundance rare earth Ce/Y/Nd/La. The samarium iron nitrogen magnetic powder comprises the following components expressed by molecular formula: (Sm) 1‑x ,RE x ) u (Fe 1‑y‑z ,T y ,M z ) v N w . In the formula, RE is the combination of rare earth elements Ce/Y/Nd/La or Ce/Y/Nd/La and other rare earth elements, and x is more than or equal to 0.33 and less than or equal to 0.95; the samarium iron nitrogen based magnetic powder has higher maximum magnetic energy product, coercive force, residual magnetic induction strength and high-temperature service performance. The RE addition leads to the increase of the saturation magnetization of the magnetic powder, the anisotropy is slightly reduced, and the T and M addition can inhibit or offset the reduction of the anisotropy of the magnetic powder caused by the RE addition. RE, T and M are elements that increase the saturation magnetization of the magnetic powder, slightly weaken, maintain and even increase the anisotropy of the magnetic powder, and the magnetic powder still maintains a high curie temperature.)

1. The utility model provides a high abundance tombarthite Ce/Y Nd/La substituted high maximum magnetic energy product's samarium iron nitrogen base magnetic powder which characterized in that samarium iron nitrogen magnetic powder is with the composition component that molecular formula expressed as: (Sm)_1-x,RE_x)_u(Fe_1-y-z,T_y,M_z)_vN_w；

In the formula, RE is the combination of rare earth elements Ce/Y/Nd/La or Ce/Y/Nd/La and other rare earth elements, and x is more than or equal to 0.33 and less than or equal to 0.95; t is one or more transition elements of 3d or 4d, y is more than or equal to 0 and less than or equal to 0.0009, and y is more than or equal to 0.11 and less than or equal to 0.60; m is one or more metals, semimetals or nonmetals, z is more than or equal to 0 and less than or equal to 0.0009, and z is more than or equal to 0.11 and less than or equal to 0.60; u is more than or equal to 1.7 and less than or equal to 2.3, v is more than or equal to 16 and less than or equal to 18, and w is more than or equal to 1.8 and less than or equal to 6;

the atomic ratio of Fe in Fe, T and M is more than or equal to 40 at.%.

2. The high abundance rare earth Ce/Y/Nd/La substituted samarium-iron-nitrogen based magnetic powder with high maximum energy product of claim 1, wherein T is one or more of Co, Ni, Cu, Mn, Cr, Mo, Ta, W, Hf, Nb, V, Zr, Ti, Zn, Ru, Rh, Pd, Pt.

3. The samarium-iron-nitrogen-based magnetic powder with high maximum energy product substituted by abundant rare earth Ce/Y/Nd/La as claimed in claim 1 or 2, wherein M is one or more of C, Si, Al, S, P, Cl, F, Ga, Sn and Sc.

Technical Field

The invention belongs to the field of rare earth permanent magnet materials, and relates to high-abundance rare earth Ce/Y/Nd/La substituted high-maximum energy product samarium-iron-nitrogen-based rare earth permanent magnet powder which is mainly used for preparing anisotropic bonded permanent magnets and can also be used for preparing sintered magnets.

Background

In 1990, Sm was developed by a Coey professor of Ireland using a gas-solid phase reaction₂Fe₁₇Nw (samarium iron nitrogen for short) compounds. Samarium iron nitrogen has excellent intrinsic magnetic properties, e.g., Curie temperature up to 473 deg.C, saturation magnetization of about 15kGs, anisotropy field H_AUp to 140 kOe. Besides having magnetic performance comparable to that of neodymium iron boron, samarium iron nitrogen has oxidation resistance and corrosion resistance superior to neodymium iron boron. While an initial degradation temperature of about 600 c prevents samarium iron nitrogen from becoming a sintered magnet, the relatively high coercivity makes samarium iron nitrogen powder suitable for bonded magnet applications.

However, the storage amount of Sm in the earth crust was only 1/5% of Nd, and the proportion of Sm in all rare earths was 3.2%. The problem of Sm shortage will manifest once samarium iron nitrogen is applied on a large scale. Ce is the most abundant rare earth element in the earth crust and accounts for 30.2 percent of the earth crust. Meanwhile, the rare earth resource is accompanied to the fact that Nd and the like are utilized and meanwhile Ce is accumulated in a large amount. The substitution of Sm by abundant rare earth Ce in samarium iron nitrogen is of great significance.

In the samarium iron nitrogen magnetic powder, the rare earth element Ce/Y/Nd/La or the combination of Ce/Y/Nd/La and other rare earth elements with 33 at% -95 at% is used for replacing Sm, so that the samarium iron nitrogen magnetic powder has higher maximum magnetic energy product, coercive force and residual magnetic induction intensity. Particularly, the maximum magnetic energy product of the samarium iron nitrogen-based rare earth permanent magnet powder prepared by partially replacing Sm with the combination of rare earth elements Ce/Y/Nd/La or Ce/Y/Nd/La and other rare earth elements is higher than that of pure samarium iron nitrogen rare earth permanent magnet powder. This is because, when Sm is partially substituted by a combination of a rare earth element Ce/Y/Nd/La or Ce/Y/Nd/La and other rare earth elements, the anisotropy of the samarium-iron-nitrogen-based rare earth permanent magnet powder is reduced from the viewpoint of intrinsic magnetic energy, but the saturation magnetization is increased. Therefore, the coercive force of the magnetic powder is slightly reduced, the residual magnetic induction strength is improved, and the maximum magnetic energy product of the samarium iron nitrogen-based rare earth permanent magnetic powder is maintained as a result of the combined action of the magnetic powder and the residual magnetic induction strength. Meanwhile, the addition of T and M can further inhibit or offset the reduction of magnetic powder anisotropy caused by the addition of RE. Thus, the synergistic effect of the addition of RE, T and M is to increase the saturation magnetization of the magnetic powder, slightly weakening, maintaining or even increasing the anisotropy of the magnetic powder, which still maintains a high curie temperature. Finally, the samarium-iron-nitrogen-based magnetic powder substituted by the high-abundance rare earth element Ce/Y/Nd/La or the combination of Ce/Y/Nd/La and other rare earth elements has higher maximum magnetic energy product, coercive force, residual magnetic induction strength and high-temperature service performance.

The samarium iron nitrogen-based rare earth permanent magnet powder with high maximum magnetic energy product is prepared by partially replacing Sm with a combination of high-abundance rare earth elements Ce/Y/Nd/La or Ce/Y/Nd/La and other rare earth elements, and has important significance for expanding the application of high-abundance rare earth in rare earth permanent magnet materials and balancing the use of the rare earth elements.

Disclosure of Invention

The invention aims to provide samarium-iron-nitrogen-based magnetic powder with high maximum energy product substituted by high-abundance rare earth elements Ce/Y/Nd/La aiming at the defects of the prior art.

The samarium iron nitrogen magnetic powder comprises the following components expressed by molecular formula: (Sm)_1-x,RE_x)_u(Fe_1-y-z,T_y,M_z)_vN_w

In the formula, RE is the combination of rare earth elements Ce/Y/Nd/La or Ce/Y/Nd/La and other rare earth elements, and x is more than or equal to 0.33 and less than or equal to 0.95; t is one or more 3d or 4d transition elements, such as Co, Ni, Cu, Mn, Cr, Mo, Ta, W, Hf, Nb, V, Zr, Ti, Zn, Ru, Rh, Pd, Pt and the like, y is more than or equal to 0 and less than or equal to 0.0009, and y is more than or equal to 0.11 and less than or equal to 0.60; m is one or more metals, semimetals or nonmetals, such as C, Si, Al, S, P, Cl, F, Ga, Sn, Sc, etc., z is more than or equal to 0 and less than or equal to 0.0009, and z is more than or equal to 0.11 and less than or equal to 0.60. U is more than or equal to 1.7 and less than or equal to 2.3, v is more than or equal to 16 and less than or equal to 18, and w is more than or equal to 1.8 and less than or equal to 6.

The atomic ratio of Fe in Fe, T, and M should be 40 at.% or more.

The samarium iron nitrogen-based powder is obtained by partially substituting samarium by high-abundance rare earth cerium. Although the replacement of Ce causes the decrease of the coercive force of the magnetic powder, the remanence of the magnetic powder is improved. Therefore, the magnetic powder still has higher maximum energy product after partial replacement. When Sm is replaced by a combination of Ce/Y/Nd/La or Ce/Y/Nd/La with other rare earth elements of less than 33 at.%, the magnetic powder is not sufficient to obtain a sufficiently high remanence and thus an optimum maximum energy product cannot be obtained. When Sm is replaced with a combination of Ce/Y/Nd/La or Ce/Y/Nd/La and other rare earth elements of more than 95 at.%, the coercive force of the magnetic powder is lowered so much that the optimum maximum energy product cannot be obtained. Explained from the viewpoint of intrinsic magnetic properties, the addition of RE results in an increase in the saturation magnetization of the magnetic powder, with a slight decrease in anisotropy, and the addition of T and M serves to suppress or offset the decrease in anisotropy of the magnetic powder caused by the addition of RE. Thus, the synergistic effect of the addition of RE, T and M is to increase the saturation magnetization of the magnetic powder, slightly weakening, maintaining or even increasing the anisotropy of the magnetic powder, which still maintains a high curie temperature. Finally, the samarium-iron-nitrogen-based magnetic powder substituted by the high-abundance rare earth Ce/Y/Nd/La or Ce/Y/Nd/La and other rare earth elements has higher maximum magnetic energy product, coercive force, residual magnetic induction strength and high-temperature service performance, and has better comprehensive performance.

Drawings

Fig. 1 is an XRD pattern of the nitrided magnetic powder in example 1.

FIG. 2 is a hysteresis loop obtained by orientation curing under a magnetic field of 2.8T and testing with VSM in the mixture of samarium-iron-nitrogen-based magnetic powder further ball-milled and crushed in example 1 and epoxy resin.

Fig. 3 is an XRD pattern of the nitrided magnetic powder in example 2.

FIG. 4 is a hysteresis loop obtained by orientation curing under a magnetic field of 2.8T and testing with VSM in the mixture of samarium iron nitrogen based magnetic powder further ball milled and crushed in example 2 and epoxy resin.

Figure 5 is an XRD pattern of the nitrided magnetic powder in example 3.

FIG. 6 is a hysteresis loop obtained by orientation curing under a magnetic field of 2.8T and testing with VSM in the mixture of samarium iron nitrogen based magnetic powder further ball milled and crushed in example 3 and epoxy resin.

Fig. 7 is an X-ray diffraction (XRD) pattern of the nitrided magnetic powder of example 7.

FIG. 8 is a hysteresis loop obtained from example 7 by further ball milling the crushed samarium iron nitrogen based magnetic powder in combination with epoxy resin and orientation curing at a magnetic field of 2.8T and testing with VSM.

FIG. 9 is a Scanning Electron Microscopy (SEM) plot of backscattered electrons (BSE) from a cross section of an ingot of a master alloy of example 7 after heat treatment.

FIG. 10 is an X-ray diffraction (XRD) pattern of the nitrided magnetic powder of example 8.

FIG. 11 is a hysteresis loop obtained from example 8 by orientation curing of further ball milled, crushed samarium iron nitrogen based magnetic powder mixed with epoxy at a magnetic field of 2.8T and testing with VSM.

FIG. 12 is a Scanning Electron Microscopy (SEM) plot of backscattered electrons (BSE) from a cross section of an ingot of a master alloy of example 8 after heat treatment.

Detailed Description

The invention is further examined with the aid of specific examples and with the aid of the accompanying drawings.

In the following examples 1.8. ltoreq. w.ltoreq.6.