Preparation method of fully-compact high-performance magnet

Abstract

The invention discloses a preparation method of a fully-compact high-performance magnet, and belongs to the technical field of magnetic materials. The preparation method comprises the following steps: preparing SmCo5 amorphous or nanocrystalline ribbon alloy and Al-Ni-Co-Cu-Fe-Ce amorphous or nanocrystalline ribbon alloy respectively by adopting a melt rapid quenching method, mixing the amorphous or nanocrystalline ribbon alloy according to a certain mass ratio, performing pre-compression molding in an oriented magnetic field, and then performing in-situ high-pressure torsion heat treatment on the magnet to obtain the final high-density magnet. The method is simple in technological process, easy to operate and beneficial to application of the high-performance composite magnet in more permanent magnet devices so as to meet market requirements.

Description

Technical Field

[0001] The invention relates to the technical field of magnetic materials, and in particular to a method for preparing a fully dense high-performance magnet. Background Art

[0002] With the continuous deepening of research on rare earth magnetic materials and the continuous expansion of application fields, it is necessary to efficiently and balancedly utilize rare earth resources and develop resource-saving high-performance rare earth permanent magnet materials to meet the needs of low-carbon economy, high-tech industries and cutting-edge defense applications. SmCo5 alloy has the highest magnetocrystalline anisotropy (K1≈15~19×10 3 kJ / m 3 ), saturation magnetization M s :0.59T, Curie temperature T c : 740℃, its theoretical magnetic energy product reaches 224.9kJ / m 3 Alnico alloy is composed of Al, Ni, Co, Cu, Fe and other elements. Among them, Fe, Co and Ni are the elements with the highest magnetic moment, and the Fe-Co phase composed of them has the highest magnetic moment. At the same time, adding a trace amount of rare earth elements to Alnico alloy helps to improve the uniaxial shape anisotropy of the hard magnetic phase.

[0003] To this end, the present invention creatively prepares SmCo5 and Al-Ni-Co-Cu-Fe-Ce amorphous or nanocrystalline thin strip alloys respectively by melt quenching method, and mixes them in a certain mass ratio and pre-presses them in an oriented magnetic field, and then the magnet is subjected to in-situ high-pressure torsion heat treatment to obtain the final high-density magnet. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention aims to provide a method for preparing a fully dense high-performance magnet.

[0005] The method for preparing a fully dense high-performance magnet of the present invention comprises the following steps: (1) The melt quenching method was used to prepare SmCo5 with nominal composition and Al with mass percentage. 8.5 Ni 15.5 Co 26 Cu4Fe 44 Ce2 amorphous or nanocrystalline thin strip alloy, copper roller speed is 10-50m / s; (2) mixing the SmCo5 and Al-Ni-Co-Cu-Fe-Ce alloy strips obtained in step (1) in a certain mass ratio and pre-pressing them in an oriented magnetic field to obtain a cylindrical magnet with a diameter of 5 cm and a height of 4 cm; (3) The cylindrical magnet obtained in step (3) is subjected to in-situ high-pressure torsion heat treatment to obtain a final high-density magnet.

[0006] Furthermore, the mass ratio of SmCo5 and Al-Ni-Co-Cu-Fe-Ce alloy strip described in step (2) is 1:0.1~1, the magnetic field strength of the orientation magnetic field is 0.1~1T, and the pressure is 50~150MPa.

[0007] Furthermore, the pressure of the in-situ high-pressure torsion heat treatment described in step (3) is 400-900 MPa, the number of torsion turns is 2-4 turns, the torsion rate is 10° / min, the in-situ heat treatment temperature is 700-1050°C, and the heat treatment time is 70-150 min.

[0008] Compared with the existing technology, the present invention has the following advantages and beneficial effects: the present invention creatively prepares SmCo5 and Al-Ni-Co-Cu-Fe-Ce amorphous or nanocrystalline thin strip alloys by melt quenching method, and mixes them in a certain mass ratio and then performs pre-pressing in an oriented magnetic field, and then the magnet is subjected to in-situ high-pressure torsion heat treatment, which can effectively increase the content of ordered structure crystalline phase in the alloy; at the same time, Al-Ni-Co-Cu-Fe-Ce alloy is added to the SmCo5 alloy, and the constituent phase of the eutectic structure formed can become the grain boundary phase of SmCo5, improve the grain boundary energy, and enhance the pinning effect of the magnetic domain, so as to improve the coercive force and magnetization intensity, and finally obtain a fully dense high-performance magnet. The process of the present invention is simple and easy to operate, which is conducive to the application of high-performance composite magnets in more permanent magnetic devices to meet market demand. DETAILED DESCRIPTION

[0009] The present invention will be further described in detail below with reference to the embodiments, but the present invention is not limited to the following embodiments.

[0010] Example 1 (1) The melt quenching method was used to prepare SmCo5 with nominal composition and Al with mass percentage. 8.5 Ni 15.5 Co 26 Cu4Fe 44 Ce2 nanocrystalline thin ribbon alloy, the copper roller speed is 15m / s; (2) mixing the SmCo5 and Al-Ni-Co-Cu-Fe-Ce alloy strips obtained in step (1) in a mass ratio of 1:0.1 and pre-pressing them in an orientation magnetic field, wherein the magnetic field strength of the orientation magnetic field is 0.1 T and the pressure is 50 MPa, to obtain a cylindrical magnet with a diameter of 5 cm and a height of 4 cm; (3) The cylindrical magnet obtained in step (3) is subjected to in-situ high-pressure torsion heat treatment, wherein the pressure of the in-situ high-pressure torsion heat treatment is 400 MPa, the number of torsion turns is 2 turns, the torsion rate is 10° / min, the in-situ heat treatment temperature is 1000°C, and the heat treatment time is 72 min, to obtain a final high-density magnet.

[0011] The fully dense high-performance magnet prepared by the present invention has a coercive force of 14.7 kOe and a magnetic energy product of 18.6 MGOe according to magnetic property tests.

[0012] Example 2 (1) The melt quenching method was used to prepare SmCo5 with nominal composition and Al with mass percentage. 8.5 Ni 15.5 Co 26 Cu4Fe 44 Ce2 nanocrystalline thin ribbon alloy, the copper roller speed is 25m / s; (2) SmCo5 and Al-Ni-Co-Cu-Fe-Ce alloy strips obtained in step (1) are mixed in a mass ratio of 1:0.5 and pre-pressed in an orientation magnetic field, wherein the magnetic field strength of the orientation magnetic field is 0.5 T and the pressure is 100 MPa, to obtain a cylindrical magnet with a diameter of 5 cm and a height of 4 cm; (3) The cylindrical magnet obtained in step (3) is subjected to an in-situ high-pressure torsion heat treatment, wherein the pressure of the in-situ high-pressure torsion heat treatment is 600 MPa, the number of torsion turns is 3 turns, the torsion rate is 10° / min, the in-situ heat treatment temperature is 850°C, and the heat treatment time is 108 min, to obtain a final high-density magnet.

[0013] The fully dense high-performance magnet prepared by the present invention is tested for magnetic properties, and the coercive force is 16.2 kOe and the magnetic energy product is 19.3 MGOe.

[0014] Example 3 (1) The melt quenching method was used to prepare SmCo5 with nominal composition and Al with mass percentage. 8.5 Ni 15.5 Co 26 Cu4Fe 44 Ce2 amorphous thin strip alloy, copper roller speed is 45m / s; (2) mixing the SmCo5 and Al-Ni-Co-Cu-Fe-Ce alloy strips obtained in step (1) in a mass ratio of 1:1 and pre-pressing them in an orientation magnetic field, wherein the magnetic field strength of the orientation magnetic field is 1 T and the pressure is 150 MPa, to obtain a cylindrical magnet with a diameter of 5 cm and a height of 4 cm; (3) The cylindrical magnet obtained in step (3) is subjected to in-situ high-pressure torsion heat treatment, wherein the pressure of the in-situ high-pressure torsion heat treatment is 800 MPa, the number of torsion turns is 4 turns, the torsion rate is 10° / min, the in-situ heat treatment temperature is 700°C, and the heat treatment time is 144 min, to obtain a final high-density magnet.

[0015] The fully dense high-performance magnet prepared by the present invention has a coercive force of 15.9 kOe and a magnetic energy product of 18.8 MGOe according to magnetic property tests.

Claims

1. A method for preparing a fully dense high-performance magnet, characterized in that The steps include: (1) The melt quenching method was used to prepare SmCo5 with nominal composition and Al with mass percentage. 8.5 Ni 15.5 Co 26 Cu4Fe 44 Ce2 amorphous or nanocrystalline thin strip alloy, copper roller speed is 10-50m / s; (2) mixing the SmCo5 and Al-Ni-Co-Cu-Fe-Ce alloy strips obtained in step (1) in a certain mass ratio and pre-pressing them in an oriented magnetic field to obtain a cylindrical magnet with a diameter of 5 cm and a height of 4 cm; (3) The cylindrical magnet obtained in step (3) is subjected to in-situ high-pressure torsional heat treatment to obtain a final high-density magnet.

2. The method for preparing a fully dense high-performance magnet according to claim 1, characterized in that: The mass ratio of SmCo5 and Al-Ni-Co-Cu-Fe-Ce alloy strip described in step (2) is 1:0.1~1, the magnetic field strength of the orientation magnetic field is 0.1~1T, and the pressure is 50~150MPa.

3. The method for preparing a fully dense high-performance magnet according to claim 1, characterized in that: The pressure of the in-situ high-pressure torsion heat treatment described in step (3) is 400-900 MPa, the number of torsion turns is 2-4 turns, the torsion rate is 10° / min, the in-situ heat treatment temperature is 700-1050°C, and the heat treatment time is 70-150 min.