CN103680793A - High magnetic energy product function material containing rhodium and preparation method thereof - Google Patents

Abstract

The invention belongs to the field of metal materials and particularly relates to a high magnetic energy product function material containing rhodium and a preparation method thereof. The material has high magnetic energy products. The preparation method is simple in technology, low in production cost and suitable for industrial production. The material comprises, by weight, 20-23% of Nd, 1-2% of Sm, 1-2% of B, 0.3-0.5% of Si, 0.7-1.2% of Co, 0.5-0.8% of Yb, 0.5-0.8% of Pb, 0.5-0.8% of P, 1-2% of Rh and the balance Fe.

Description

A kind of rhodium-containing high magnetic energy product functional material and preparation method thereof

technical field

The invention belongs to the field of metal materials, and in particular relates to a rhodium-containing high magnetic energy product functional material and a preparation method thereof.

Background technique

Application No. CN200710020515.8 discloses a preparation method of NdFeB magnetic powder, including a vacuum smelting process, a vacuum rapid quenching process, a crystallization process, and a sieving process. Between the crystallization process and the sieving process, an increase of A warm-pressing process is carried out, and the warm-pressing process is under the condition of 130-180° C. and a pressure of 60-150 MPa for 30-60 minutes.

The magnetic energy product of the above invention is 10-14MGoe, the magnetic energy product is relatively low, and the sintering method cannot guarantee the stability of the structure and performance of the material.

Contents of the invention

Purpose of the present invention is exactly at above-mentioned technical defect, provides a kind of rhodium-containing high magnetic energy product functional material, and this material has higher magnetic energy product.

Another object of the present invention is to provide a method for preparing a rhodium-containing high magnetic energy product functional material. The preparation method has simple process, low production cost and is suitable for industrial production.

The purpose of the present invention is achieved through the following technical solutions:

A rhodium-containing high magnetic energy product functional material is characterized in that: the weight percentage of each component in the material is: Nd 20-23%, Sm 1-2%, B 1-2%, Si 0.3-0.5%, Co 0.7-1.2%, Yb 0.5-0.8%, Pb 0.5-0.8%, P 0.5-0.8%, Rh 1-2%, and the rest is Fe.

The preparation method of above-mentioned rhodium-containing high magnetic energy product functional material, its steps are:

(1) Nd, Sm, B, Si, Co, Yb, Pb, P, Rh, and Fe are used for batching according to the above weight percentages, and the purity of each raw material is greater than 99.9%; P is added in the form of ferrophosphorus, and ferrophosphorus Contains P 25%;

(2) Melting the raw materials in a vacuum induction furnace at a melting temperature of 1660-1780°C and standing for 2-4 minutes to obtain a master alloy liquid;

(3) Casting the master alloy liquid onto the roller below the taphole of the induction furnace, the master alloy liquid encounters the rotating roller and is dragged by the rim of the roller to form a casting belt;

(4) Cool the cast strip naturally for 5-10 minutes, and then put the cast strip into the hydrogen crushing furnace for hydrogen crushing. The vacuum degree of the hydrogen crushing furnace is 0.05-0.1Pa, and the pressure in the furnace is 0.9-1.3atm; the temperature is 200-310°C, hydrogen crushing time 40-50 minutes, to obtain coarse powder;

(5) Put the coarse powder into the airflow mill, blow the coarse powder up with high-pressure airflow, and become fine powder through collision with each other. The powder making pressure of the airflow mill is 5-7 atm, and the speed of the airflow mill sorting wheel is 3000~ 3300r/min;

(6) Put the fine powder into the mold and press it into the desired shape using pressing equipment;

(7) After molding, take out the molded part and put it into a sintering microwave oven. The atmosphere of the sintering furnace is argon, the sintering temperature is 1040-1100°C, and the microwave power is 3-6kW. After sintering for 100-200 minutes, take it out after natural cooling with the furnace The sintered molded part can obtain the NdFeB magnetic material.

The rotational speed of the roller rim described in step (3) is 8-11m/s; the thickness of the casting belt is 1-2mm, and the width is 5-20mm; the coarse powder particle size in step (4) is 500-800μm .

The particle size of the fine powder in step (5) is 2-5 μm; the molding pressure in step (6) is 0.02-0.05 MPa.

Compared with the prior art, the present invention has the following beneficial effects:

The Co and Yb adopted in the material of the present invention will affect the structure of the hard magnetic phase, the intrinsic magnetism and the macroscopic magnetism of the magnet, etc., and the doping elements Co and Yb do not replace the atoms in the tetragonal phase, and are distributed in the hard magnetic phase in the form of elutes. Inside the magnetic tetragonal phase, a new phase can also be formed at the grain boundary of the tetragonal phase, thereby replacing the previous Nd-rich phase or B-rich phase, and achieving the purpose of improving the boundary microstructure of the hard magnetic grain.

The coercive force of the main phase can be improved by the Nd, Sm, and Rh elements in the material entering the Nd matrix. Yb and Pb can reduce the wetting angle between the Nd-rich phase and the Nd2Fe14B phase, inhibit the growth of the Nd2Fe14B phase, thereby reducing the defect density of the Nd2Fe14B phase interface and improving the magnetic energy product of the material. Part of the B atoms replaced by Pb in the material can refine the crystal grains and improve the remanence of the material. Rh element can improve Curie temperature, oxidation resistance and corrosion resistance.

The invention adopts the process design of alloy composition optimization and microwave sintering combination, which can ensure the sintering uniformity of the material, and the obtained alloy has uniform composition and performance, and the obtained material has a higher magnetic energy product.

In the preparation process of the present invention, rare elements are used in small amounts, and the cost of raw materials is low; in addition, the process design combining alloy composition optimization and microwave sintering ensures the uniformity of alloy composition, structure and performance, thus ensuring the quality of the alloy . The preparation process of the invention is simple, the produced alloy has good properties, and is very convenient for industrialized production.

The material prepared by the invention is mainly used in the manufacture of instruments and meters, communication equipment, rotating machinery, magnetic therapy equipment and the like.

Description of drawings

Fig. 1 is a structure diagram of an amorphous alloy of the material of the present invention.

It can be seen from Fig. 1 that the structure of the rhodium-containing high magnetic energy product functional material of the present invention is dense and uniform.

Detailed ways

Embodiment one:

The preparation method of rhodium-containing high magnetic energy product functional material of the present invention, concrete steps are as follows:

(1) Take Nd 20%, Sm 1%, B 1%, Si 0.3%, Co 0.7%, Yb 0.5%, Pb 0.5%, P 0.5%, Rh 1% according to the following weight percentages, and the rest is Fe for batching ; Wherein the purity of Nd, Sm, B, Si, Co, Yb, Pb, P, Rh and Fe is greater than 99.9%;

(2) Melting the raw materials in a vacuum induction furnace at a melting temperature of 1660°C and standing for 2 minutes to obtain a master alloy liquid;

(3) Cast the master alloy liquid onto the roller below the taphole of the induction furnace. The master alloy liquid encounters the rotating roller and is dragged by the roller rim to form a casting belt; the rotational speed of the roller rim is 8m/s; the thickness of the casting belt is about 1mm and the width is 15mm;

(4) Cool the cast strip naturally for 5 minutes, and then put the cast strip into the hydrogen crushing furnace for hydrogen crushing. The vacuum degree of the hydrogen crushing furnace is 0.05Pa, and the pressure in the furnace is 0.9atm; the temperature is 200°C, and the hydrogen crushing time is Be 40 minutes, obtain coarse powder, particle size is about 500 μ m;

(5) Put the coarse powder into the jet mill, blow the coarse powder up with high-pressure airflow, and make fine powder through collision with each other. The powder making pressure of the jet mill is 5atm, and the speed of the jet mill sorting wheel is 3000r/min; The particle size of the fine powder is about 2 μm;

(6) Put the fine powder into the mold and press it into the desired shape with pressing equipment, the molding pressure is 0.02MPa;

(7) After molding, take out the molded part and put it into a sintering microwave oven. The atmosphere of the sintering furnace is argon, the sintering temperature is 1040 ° C, and the microwave power is 3 kW. After sintering for 100 minutes, take out the sintered molded part after natural cooling in the furnace to obtain neodymium Fe-boron magnetic material.

Embodiment two:

The preparation method of rhodium-containing high magnetic energy product functional material of the present invention, concrete steps are as follows:

(1) Take Nd 23%, Sm 2%, B 2%, Si 0.5%, Co 1.2%, Yb 0.8%, Pb 0.8%, P 0.8%, Rh 2% according to the above weight percentage, and the rest is Fe for batching ; Wherein the purity of Nd, Sm, B, Si, Co, Yb, Pb, P, Rh and Fe is greater than 99.9%;

(2) Melting the raw materials in a vacuum induction furnace at a melting temperature of 1700°C and standing for 3 minutes to obtain a master alloy liquid;

(3) Cast the master alloy liquid onto the roller below the taphole of the induction furnace. The master alloy liquid encounters the rotating roller and is dragged by the roller rim to form a casting belt; the rotational speed of the roller rim is 9m/s; the thickness of the casting belt is about 1.5mm, and the width is 10mm;

(4) Cool the cast strip naturally for 8 minutes, and then put the cast strip into the hydrogen crushing furnace for hydrogen crushing. The vacuum degree of the hydrogen crushing furnace is 0.08Pa, and the pressure in the furnace is 1.1atm; the temperature is 250°C, and the hydrogen crushing time is After 45 minutes, coarse powder was obtained, with a particle size of about 600 μm;

(5) Put the coarse powder into the jet mill, blow the coarse powder up with high-pressure airflow, and make it into a fine powder through collision with each other. The powder making pressure of the jet mill is 6atm, and the speed of the jet mill sorting wheel is 3100r/min; The particle size of the fine powder is about 3 μm;

(6) Put the fine powder into the mold and press it into the desired shape with pressing equipment, the molding pressure is 0.04MPa;

(7) After molding, take out the molded part and put it into a sintering microwave oven. The atmosphere of the sintering furnace is argon, the sintering temperature is 1080 ° C, and the microwave power is 4 kW. After sintering for 150 minutes, take out the sintered molded part after natural cooling in the furnace to obtain neodymium Fe-boron magnetic material.

Embodiment three:

The preparation method of rhodium-containing high magnetic energy product functional material of the present invention, concrete steps are as follows:

(1) Take Nd 22%, Sm 1.5%, B 1.5%, Si 0.4%, Co 0.9%, Yb 0.7%, Pb 0.7%, P 0.56%, Rh 1.5% according to the above weight percentage, and the rest is Fe for batching ; Wherein the purity of Nd, Sm, B, Si, Co, Yb, Pb, P, Rh and Fe is greater than 99.9%;

(2) Melting the raw materials in a vacuum induction furnace at a melting temperature of 1780°C and standing for 4 minutes to obtain a master alloy liquid;

(3) Cast the master alloy liquid onto the roller below the taphole of the induction furnace. The master alloy liquid encounters the rotating roller and is dragged by the roller rim to form a casting belt; the rotational speed of the roller rim is 11m/s; the thickness of the casting belt is about 2mm and the width is 8mm;

(4) Cool the cast strip naturally for 10 minutes, then put the cast strip into the hydrogen crushing furnace for hydrogen crushing. The vacuum degree of the hydrogen crushing furnace is 0.1Pa, and the pressure in the furnace is 1.3atm; the temperature is 310°C, and the hydrogen crushing time is After 50 minutes, coarse powder was obtained, with a particle size of about 800 μm;

(5) Put the coarse powder into the jet mill, blow the coarse powder up with high-pressure airflow, and make fine powder through collision with each other. The powder making pressure of the jet mill is 7atm, and the speed of the jet mill sorting wheel is 3300r/min; Fine powder particle size is about 5μm;

(6) Put the fine powder into the mold and press it into the desired shape with pressing equipment, the molding pressure is 0.05MPa;

(7) After molding, take out the molded part and put it into a sintering microwave oven. The atmosphere of the sintering furnace is argon, the sintering temperature is 1100 ° C, and the microwave power is 6 kW. After sintering for 200 minutes, take out the sintered molded part after natural cooling in the furnace to obtain neodymium Fe-boron magnetic material.

Embodiment 4: (ingredient distribution ratio is not within the proportion range involved in the present invention)

The weight percent content of each component in the rhodium-containing high magnetic energy product functional material of the present invention: Nd 18%, Sm 0.6%, B 0.5%, Si 0.2%, Co 0.5%, Yb 0.3%, Pb 0.4%, P 0.3%, Rh 0.8%, all the other carry out batching for Fe; Its preparation process is with embodiment one.

Embodiment five: (ingredient distribution ratio is not within the scope of the ratio involved in the present invention)

The weight percent content of each component in the rhodium-containing high magnetic energy product functional material of the present invention: Nd 24%, Sm 3%, B 3%, Si 0.6%, Co 1.4%, Yb 0.9%, Pb 0.9%, P 0.9%, Rh 3%, all the other carry out batching for Fe; Its preparation process is with embodiment one.

Table I

Alloy material number material ingredient Magnetic energy product/MGOe Comparative material one Materials obtained from CN200710020515.8 application 10-14 NdFeB Magnets 1 The neodymium-iron-boron magnet that embodiment one makes 16 NdFeB magnet II The neodymium-iron-boron magnet that embodiment two makes 18 NdFeB magnet three The neodymium-iron-boron magnet that embodiment three makes 19 NdFeB magnet four The neodymium-iron-boron magnet that embodiment four makes 14 NdFeB magnet five The neodymium-iron-boron magnet that embodiment five makes 15

It can be seen that the addition of Nd, Sm, B, Si, Co, Yb, Pb, P, and Rh elements in the material of the present invention contributes to the improvement of the magnetic energy product of the alloy. But beyond the scope specified in this case, the magnetic energy product not only did not increase, but decreased. The reason is that these elements will react with each other to form non-magnetic compounds, which reduces the effective effect of the elements themselves.

Claims (4)

1. a rhodium-containing high energy product functional material, is characterized in that: in this material, the weight percentage of each composition is: Nd 20-23%, Sm 1-2%, B 1-2%, Si 0.3-0.5 %, Co 0.7-1.2%, Yb 0.5-0.8%, Pb 0.5-0.8%, P 0.5-0.8%, Rh 1-2%, all the other are Fe.

2. the preparation method of rhodium-containing high energy product functional material described in claim 1, the steps include:

(1) according to above-mentioned percentage by weight, get respectively Nd, Sm, B, Si, Co, Yb, Pb, P, Rh and Fe and prepare burden, the purity of each raw material is all greater than 99.9%; P adds with the form of ferrophosphorus, and ferrophosphorus is containing P 25%;

(2) raw material is put into vaccum sensitive stove melting, smelting temperature is 1660-1780 ℃, and standing 2-4 minute obtains foundry alloy liquid;

(3) by foundry alloy liquid cast to the transfer roller of induction furnace tapping hole below, foundry alloy liquid runs into the transfer roller of rotation, by transfer roller wheel rim, is pulled and forms Cast Strip;

(4) by the naturally cooling 5-10 minute in Cast Strip, then Cast Strip being put into hydrogen crushing furnace, to carry out hydrogen broken, and the vacuum degree of hydrogen crushing furnace is 0.05～0.1Pa, and stove internal gas pressure is 0.9～1.3atm; Temperature is 200-310 ℃, and the broken time 40-50 minute of hydrogen, obtains meal;

(5) meal is put into airflow milling, with high pressure draught, meal is blown afloat, thereby become fine powder by collision each other, airflow milling powder pressure 5-7atm, jet mill sorting wheel rotating speed is 3000～3300r/min;

(6) fine powder is put into mould, use press device to be pressed into required shape;

(7) after moulding, take out molded part, put into sintered microwave stove, sintering furnace atmosphere is argon gas, sintering temperature is 1040-1100 ℃, microwave power is 3-6kW, and sintering, after 100～200 minutes, obtains Nd-Fe-B permanent magnet with the naturally cooling rear taking-up sinter molding part of stove.

3. preparation method according to claim 2, is characterized in that: described in step (3), the rotational line speed of transfer roller wheel rim is 8-11m/s; The thickness of Cast Strip is 1-2mm, and width is 5-20 mm; In step (4), coarse granularity is 500-800 μ m.

4. according to the preparation method described in claim 2 or 3, it is characterized in that: powder particle size described in step (5) is 2-5 μ m; In step (6), briquetting pressure is 0.02-0.05MPa.