Supersaturated solid solution soft magnetic material and preparation method thereof

Patent metadata

Field	Value
Publication number	US-11791076-B2
Application number	US-202217719067-A
Country	US
Kind code	B2
Filing date	Apr 12, 2022
Priority date	Jan 18, 2022
Publication date	Oct 17, 2023
Grant date	Oct 17, 2023

Abstract

A supersaturated solid solution soft magnetic material and a preparation method thereof are provided, belonging to the field of metal soft magnetic technologies. The supersaturated solid solution soft magnetic material is soft magnetic alloy with proportions of 72.0˜78.0 at % Fe, 12.0˜18.0 at % Si, 4.0˜12.0 at % Co and 1.0˜3.0 at % Ti. The preparation method uses molten glass purification or electromagnetic levitation melting to an alloy melt with a target supercooling degree, increases the solid solubility of the Ti element in α-Fe (Si, Co), and promotes the formation of supersaturated solid solution of Ti, thereby achieving the goal that the magnetocrystalline anisotropy constant and the magnetostriction coefficient tend to be zero. Ti element is uniformly distributed in the α-Fe (Si, Co) after supercooled solidification analyzed by X-ray energy spectrometer, a supersaturated solid solution alloy without Ti precipitation is obtained, and the soft magnetic alloy has low coercivity and high permeability.

First claim

What is claimed is:

1. A preparation method of a supersaturated solid solution soft magnetic material, comprising:
performing one of molten glass purification and electromagnetic levitation melting on raw materials of the supersaturated solid solution soft magnetic material to obtain the supersaturated solid solution soft magnetic material;
wherein the raw materials of the supersaturated solid solution soft magnetic material comprises: iron (Fe), silicon (Si), cobalt (Co) and titanium (Ti);
wherein proportions of the raw materials comprise 72.0-78.0 atomic percent (at %) Fe, 12.0-18.0 at % Si, 4.0-12.0 at % Co and 1.0-3.0 at % Ti.

2. The preparation method according to claim 1 , wherein the molten glass purification comprises:
step (1), weighing the raw materials according to the proportions, and performing one of arc melting and induction melting on the raw materials under one of a first vacuum condition and a first protective atmosphere to obtain a master alloy;
step (2), placing the master alloy and a glass denucleating agent into a quartz glass tube to make an upper surface and a lower surface of the master alloy be covered with the glass denucleating agent;
step (3), placing the quartz glass tube with the master alloy and the glass denucleating agent in a radio-frequency induction coil, and then heating the radio-frequency induction coil with a certain power under one of a second vacuum condition and a second protective atmosphere to melt the glass denucleating agent and coat the melted glass denucleating agent onto surfaces of the master alloy through metal heat conduction;
step (4), increasing the heating power of the radio-frequency induction coil to melt the master alloy coated with the melted glass denucleating agent to obtain a resultant alloy melt, heating the resultant alloy melt to a temperature in a range of 1300-1500 degrees Celsius (° C.) to make the resultant alloy melt overheat, stopping the heating of the resultant alloy melt after heat preserving the resultant alloy melt for 2-5 minutes, and cooling the resultant alloy melt naturally to obtain a resultant alloy; and
step (5), cycle overheating comprising: repeatedly performing a treatment of “the heating of the resultant alloy melt—the heat preserving of the resultant alloy melt—the cooling of the resultant alloy melt” on the resultant alloy, measuring a temperature of the resultant alloy melt in real time, stopping the treatment when the resultant alloy melt obtains a target supercooling degree, and obtaining the supersaturated solid solution soft magnetic material after supercooling solidification of the resultant alloy melt.

3. The preparation method according to claim 1 , wherein the electromagnetic levitation melting comprises:
step (a), weighing the raw materials according to the proportions, and performing one of arc melting and induction melting on the raw materials under one of a third vacuum condition and a third protective atmosphere to obtain a master alloy;
step (b), placing the master alloy in a suspended electromagnetic field to suspend the master alloy in a center of a heating coil depending on a Lorentz force formed by an interaction between the suspended electromagnetic field and an induced current;
step (c), inductively heating the suspended master alloy under one of a fourth vacuum condition and a fourth protective atmosphere by using the heating coil to obtain a resultant alloy melt, heating the resultant alloy melt to a temperature in a range of 1300-1500° C. to make the resultant alloy melt overheat, stopping the heating of the resultant alloy melt after heat preserving the resultant alloy melt for 2-5 minutes, and then cooling the resultant alloy melt naturally to a resultant alloy; and
step (d), cycle overheating comprising: repeatedly performing a treatment of “the heating of the resultant alloy melt—the heat preserving of the resultant alloy melt—the cooling of the resultant alloy melt” on the resultant alloy, and measuring an temperature of the resultant alloy melt in real time, stopping the treatment when the resultant alloy melt obtains a target supercooling degree, and making the resultant alloy melt nucleate and solidify to obtain the supersaturated solid solution soft magnetic material.

4. The preparation method according to claim 2 , wherein the step (1) comprises:
using electromagnetic stirring to perform the one of arc melting and induction melting on the raw materials, and repeatedly melting the master alloy 4-6 times to ensure that the raw materials distribute uniformly in the master alloy.

5. The preparation method according to claim 2 , wherein each of the first vacuum condition and the second vacuum condition is in a vacuum state of less than 5×10 −3 Pascals (Pa); and
wherein each of the first protective atmosphere and the second protective atmosphere is one of an argon gas and a nitrogen gas with a purity no less than 99.9 volume percent (vol %).

6. The preparation method according to claim 2 , wherein the glass denucleating agent comprises:
main bodies including silicon dioxide (SiO 2 ) and sodium silicate (Na 2 SiO 3 ); and
stabilizers including calcium oxide (CaO), magnesium oxide (MgO), aluminium oxide (Al 2 O 3 ) and ferric oxide (Fe 2 O 3 );
wherein proportions of the respective main bodies and the stabilizers are 59.0-75.0 wt % SiO 2 , 15.0-31.0 wt % Na 2 SiO 3 , 4.0-7.0 wt % CaO, 1.8-2.0 wt % MgO, 1.0-2.0 wt % Al 2 O 3 , and 0.1-0.3 wt % Fe 2 O 3 .

7. The preparation method according to claim 6 , wherein the glass denucleating agent is prepared by:
mixing SiO 2 , Na 2 SiO 3 , CaO, MgO, Al 2 O 3 and Fe 2 O 3 in the proportions to obtain a mixture, and burning the mixture at a temperature in a range of 800-900° C. for 5-8 hours;
wherein a mass of the glass denucleating agent is in a range of 20-25% of a mass of the master alloy.

8. The preparation method according to claim 3 , wherein the step (a) comprises:
using electromagnetic stirring to perform the one of arc melting and induction melting on the raw materials, and repeatedly melting the master alloy 4-6 times to ensure that the raw materials distribute uniformly in the master alloy.

9. The preparation method according to claim 3 , wherein each of the third vacuum condition and the fourth vacuum condition is in a vacuum state of less than 5×10 −3 Pa; and
wherein each of the third protective atmosphere and the fourth protective atmosphere is one of an argon gas and a nitrogen gas with a purity no less than 99.9 vol %.

Assignees

• Univ Zhejiang

Inventors

• Yan Mi
• Wu Chen
• Chen Qiming
• Jin Jiaying

Classifications

• H01F1/14766 Primary

  Fe-Si based alloys · CPC title

• C22C33/06

  using master alloys · CPC title

• C22C38/02 Primary

  containing silicon · CPC title

• C22C38/10

  containing cobalt · CPC title

• C22C38/14

  containing titanium or zirconium · CPC title