CN107739801A - The method that one kind prepares Fe Ga (Al) magnetostriction strip in razor-thin using tertiary recrystallization - Google Patents

Abstract

The invention provides a method for preparing Fe-Ga(Al) magnetostrictive ultra-thin strips by using triple recrystallization, which belongs to the field of magnetic materials, and the material composition is Fe _100-x-y Ga _x M _y (x=13-30 ), Fe _100-x-y Al _x M _y (x=10-30) where M is one or more of AlN, NbC, MnS, TiC, VC, y=0.01-1.0, the above x, y are all is the atomic fraction. The key points of the process are: using the directional solidification method to obtain an alloy ingot with a <100> orientation, and obtaining a 0.25-0.35mm thick Gaussian texture sheet after solid solution, hot rolling, warm rolling and cold rolling through primary and secondary recrystallization, The sheet is cold-rolled to 0.02-0.05 mm, and recrystallized three times to obtain Fe-Ga(Al) magnetostrictive ultra-thin strip with cubic texture. The advantages of the present invention are: (1) have large magnetostriction, small eddy current loss, can greatly improve the power and frequency of the power ultrasonic transducer; (2) have good toughness, can overcome electromagnetic ultrasonic guided wave detection Due to the limitation of toughness, the currently used magnetostrictive thin strips cannot detect the defects in special-shaped parts, which meets the special detection requirements.

Description

A Method for Preparing Fe-Ga(Al) Magnetostrictive Ultra-thin Strips Using Three Recrystallization

technical field

The invention belongs to the field of magnetic materials, in particular to the preparation of Fe-Ga(Al) magnetostrictive ultra-thin strips.

Background technique

Ferromagnetic substances have a structure similar to crystals. When the magnetization state of ferromagnetic materials changes, its magnetic domains will rotate, causing their length or volume to change slightly. This phenomenon is called magnetostrictive effect. There are two manifestations of the effect: linear magnetostriction and bulk magnetostriction. When a ferromagnetic substance is magnetized, it will be accompanied by spontaneous deformation of the crystal lattice, that is, elongation and shortening along the magnetization direction, which is called linear magnetostriction, and the linear magnetostriction coefficient λ=ΔL/L (L is the original length of the material , ΔL is the change in the length of the material under the external magnetic field), when λ>0, that is, under the external magnetic field, the material elongates along the direction of the magnetic field, which is called the positive magnetostrictive effect, indicating that with the increase of the external magnetic field, the strain of the material is Elongation, on the contrary, λ<0, is called negative magnetostrictive effect, indicating that with the increase of the external magnetic field, the strain of the material is shortened. Volume magnetostriction refers to the phenomenon that the volume of a magnet expands or contracts when its magnetization state changes. Since the change of volume magnetostriction is very small, the practical value is not high. Usually, the practical application is the material line magnetostriction effect. The maximum strain generated by the material under the external magnetic field is called the saturation magnetostriction coefficient (λs), The size of the corresponding magnetic field is called the saturation magnetization field (Hs).

Since the discovery of the magnetostrictive effect, the application prospects of magnetostrictive materials in energy conversion, driving, and sensing technologies have been attracting attention. Fe-Ga(Al) alloy is a new type of magnetostrictive material after traditional magnetostrictive materials (Ni, Fe-Al, etc.) and Tb-Dy-Fe rare earth giant magnetostrictive materials, rare earth giant magnetostrictive materials The material has a high magnetostriction coefficient, but the cost is high and the mechanical properties are poor. Fe-Ga(Al) alloy fills the gap between traditional magnetostrictive materials and rare earth giant magnetostrictive materials. It not only has good mechanical properties, but also has a large magnetostrictive coefficient, and has broad application prospects.

Due to the low resistivity of bulk Fe-Ga(Al), the eddy current loss is serious in high-frequency applications, and it is difficult to meet the requirements of high-frequency applications of power ultrasonic transducers. The eddy current loss decreases significantly as the thickness of the alloy decreases. Since the Fe-Ga(Al) alloy has excellent mechanical properties, it is hoped that the method of preparing an extremely thin strip by rolling can reduce the eddy current loss and realize the power ultrasonic transducer High power, high frequency applications.

At present, magnetostrictive materials are also used in electromagnetic ultrasonic transducers. The magnetostrictive thin strips are fixed on the test piece with epoxy resin as shown in Figure 2. The thickness of the magnetostrictive thin strips used is 0.2mm Left and right, toughness has a certain limit, and for the detection of special-shaped parts such as railway track rails and "twist-style" bridge chains, steel wires, etc., the magnetostrictive thin strips currently prepared are difficult to meet the use requirements, so it is hoped to use Fe-Ga( Al) alloys have good mechanical properties. Fe-Ga(Al) ultra-thin strips (0.02-0.05 mm) are prepared by rolling to improve the toughness of magnetostrictive materials and realize ultrasonic testing of special components.

Contents of the invention

The purpose of the present invention is to provide a kind of utilizing triple recrystallization to prepare high-performance Fe-Ga (Al) magnetostriction extremely thin strip, make the thickness of thin strip in the thick range of 0.02～0.05mm, and have eddy current loss small, big The advantages of magnetostriction and good toughness can realize the application of high power and high frequency in power ultrasonic transducers, and can also replace the existing magnetostrictive thin strips for electromagnetic ultrasonic guided wave detection, and realize the detection of special-shaped parts .

Concrete implementation steps of the present invention are:

(1) Preparation of 0.25-0.35mm thick Fe-Ga(Al) rolled sheet:

(a) The alloy ingot whose material composition is Fe _100-xy Ga _x M _y or Fe _100-xy Al _x M _y is obtained by directional solidification, where x and y are atomic fractions, and the balance is iron. The alloy ingot is subjected to solution treatment, and then the alloy ingot is wire-cut into slabs with a thickness of 30 to 35 mm;

The value of x in the Fe _100-xy Ga _x M _y is 13-30, and the value of y is 0.01-1.0; the value of x in Fe _100-xy Al _x M _y is 10-30, and the value of y is 0.01-1.0;

(b) The slab obtained in step (a) is firstly hot-rolled at 900-1200°C for 30-90 minutes to 2-3mm, then warm-rolled at 300-700°C for 10-60min to 1-1.5mm, and then cold-rolled to 0.25mm ~0.35mm, the flakes are subjected to primary recrystallization at 700~850°C and secondary recrystallization at 1000~1250°C to obtain Fe-Ga(Al) flakes with Gaussian texture.

(2) Preparation of 0.02-0.05mm thick Fe-Ga(Al) extremely thin strip:

(c) Heat the sheet obtained in step (b) at 300-700°C for 10-40 minutes, roll the Goss-textured sheet at a reduction of 50-85% on a cold rolling mill, and return it to the furnace once each rolling pass Keep warm for 1-5 minutes, when rolling to a thickness of 0.12-0.2mm, return to the furnace for 1-3 minutes for every 4-5 passes of rolling, until rolling to a thickness of 0.02-0.05mm;

(d) heat-treating the ultra-thin strip obtained in step (c) after sealing the tube or placing the ultra-thin strip in a vacuum furnace to obtain an ultra-thin strip with a cubic texture.

M in the Fe _100-xy Ga _x M _y or Fe _100-xy Al _x M _y in step (a) is one or more of AlN, NbC, MnS, TiC, and VC.

The alloy ingot in step (a) is an alloy ingot with <100> orientation obtained by directional solidification.

The solid solution treatment in step (a) is to perform solid solution treatment on the alloy ingot at 1200-1300° C. for 1-5 hours.

The heat treatment process in step (d) is short-term annealing at 900-1100° C. for 10-60 seconds, and heat preservation at 1100-1250° C. for 10-12 hours.

The heat treatment in the vacuum furnace in step (d) is carried out under an inert gas or hydrogen protective atmosphere.

The features of the present invention are:

1) The directional solidification method is used to obtain alloy ingots with <100> orientation. During the rolling process, some favorable orientation textures are retained due to texture inheritance, which is conducive to the generation of tertiary recrystallization cubic textures;

2) The high-temperature solid-solution alloy ingot makes the internal inhibitors AlN, NbC, MnS, TiC, etc. fully re-dissolve into fine dispersed particles, which act as inhibitors for subsequent recrystallization;

3) The rolled ultra-thin strip will undergo primary and secondary recrystallization to form a transitional texture (210)[001] in the subsequent short-term annealing, and three recrystallizations will form a cubic texture during the holding stage;

4) 0.02-0.05mm thick Fe-Ga(Al) ultra-thin strip can increase the power and frequency of the power ultrasonic transducer due to its large magnetostriction and ultra-thin thickness, and reduce the eddy current loss of the transducer. Output power P∝λ, eddy current loss P _e ∝t ² /ρ, λ, t, ρ respectively represent the magnetostriction coefficient, thickness and resistivity of the magnetostrictive material;

5) The thinner the Fe-Ga(Al) strip, the better its toughness. It can be used for electromagnetic ultrasonic guided wave detection to realize online monitoring and detection of some irregular parts, and overcome the traditional use of magnetostrictive thin strips due to poor toughness. And detection is limited.

The advantages of the present invention are:

1) The ultra-thin Fe-Ga(Al) strip with a thickness of 0.02-0.05mm has a large magnetostriction value and small eddy current loss, which can greatly improve the power of the power ultrasonic transducer and realize high power, High-frequency applications have important practical significance for the technological change of existing ultrasonic transducers;

2) The extremely thin Fe-Ga(Al) magnetostrictive strip has good toughness and can be used for electromagnetic ultrasonic guided wave detection, making up for the limitation of toughness of existing magnetostrictive thin strips in electromagnetic ultrasonic guided wave detection technology. The shortcomings of detecting defects in special-shaped parts meet special inspection needs.

Description of drawings

Figure 1 is the λ-H curve of Fe-Ga(Al) magnetostrictive extremely thin strip.

Fig. 2 is a schematic diagram of the application of the magnetostrictive thin strip in the electromagnetic ultrasonic transducer.

Fig. 3 is an ODF diagram of three recrystallizations of a magnetostrictive extremely thin ribbon.

Detailed ways

Although the specific implementation of the present invention has been described in detail with reference to the following exemplary embodiments of the present invention, it should be noted that without departing from the core of the present invention, any simple deformation, modification or other Equivalent replacements that can be made by a skilled person without creative effort all fall within the protection scope of the present invention.

Embodiment 1: The method for preparing Fe-Ga magnetostrictive ultra-thin strips by three times of recrystallization:

1. Prepare Fe ₈₃ Ga ₁₇ (NbC) _0.1 (x=13-30) (the above are atomic fractions), use the directional solidification method to obtain an alloy ingot with a <100> orientation, and solidify the alloy ingot at 1300 ° C for 4 hours Solvent treatment, cutting the alloy ingot wire into 34mm thick slab;

2. The slab obtained in step (1) is firstly hot-rolled at 1000°C for 60 minutes to 2.5mm, then warm-rolled at 500°C for 20 minutes to 1.5mm, and then cold-rolled to 0.3mm, and the sheet is subjected to primary recrystallization at 800°C and 1150°C ℃ secondary recrystallization treatment to obtain 0.3mm thick Fe-Ga flakes with Gaussian texture;

3. The Fe-Ga sheet obtained in step (2) is kept at 600°C for 30 minutes, and the Goss texture sheet is rolled on a cold rolling mill at a reduction of 50 to 85%, and initially returned to the furnace for 3 minutes for each rolling pass. When rolling to a thickness of 0.2mm, return to the furnace for 1 minute for every 4 to 5 passes until rolling to a thickness of 0.05mm;

4. Seal the Fe-Ga ultra-thin strip obtained in step (3) and heat-treat it in a box furnace or place the ultra-thin strip in a vacuum furnace with an inert gas or hydrogen protective atmosphere. The heat treatment process is carried out at 1050 ° C. Short-term annealing for 40 s, holding at 1200°C for 10 h, finally obtained an ultra-thin ribbon with a cubic texture, and the saturation magnetostriction value reached 250 ppm, as shown in Figure 1, and the ODF diagram of the cubic texture is shown in Figure 3.

Embodiment 2: Utilize the method for preparing Fe-Ga magnetostrictive ultra-thin strip by three times of recrystallization:

1. Prepare Fe ₈₁ Ga ₁₉ (MnS) _0.1 (x=13-30) (the above are atomic fractions), use the directional solidification method to obtain an alloy ingot with a <100> orientation, and solidify the alloy ingot at 1300°C for 4h Solvent treatment, cutting the alloy ingot wire into 35mm slabs;

2. The slab obtained in step (1) is firstly hot-rolled at 1100°C for 60 minutes to 2.5mm, then warm-rolled at 550°C for 15 minutes to 1.3mm, and then cold-rolled to 0.31mm, and the sheet is subjected to primary recrystallization at 800°C and 1150mm ℃ secondary recrystallization treatment to obtain 0.31mm thick Fe-Ga flakes with Gaussian texture;

3. The Fe-Ga sheet obtained in step (2) is kept at 600°C for 30 minutes, and the Goss texture sheet is rolled on a cold rolling mill at a reduction of 50 to 85%, and initially returned to the furnace for 3 minutes for each rolling pass. When rolling to a thickness of 0.2mm, return to the furnace for 1 minute for every 4 to 5 passes until the thickness is 0.03mm;

4. Seal the Fe-Ga ultra-thin strip obtained in step (3) and heat-treat it in a box furnace or place the ultra-thin strip in a vacuum furnace with an inert gas or hydrogen protective atmosphere. The heat treatment process is carried out at 1050 ° C. Short-time annealing for 40s, and holding at 1200°C for 10h, finally obtained Fe-Ga extremely thin strips with cubic texture.

Embodiment 3: The method for preparing Fe-Al magnetostrictive ultra-thin strips by three times of recrystallization:

1. Prepare Fe ₈₁ Al ₁₉ (MnS) _0.1 (x=10-30) (the above are atomic fractions), and use the directional solidification method to obtain an alloy ingot with a <100> orientation. The alloy ingot is solidified at 1250°C for 3.5h Solution treatment, wire cutting the alloy ingot into 35mm slabs;

2. The slab obtained in step (1) is firstly hot-rolled at 1000°C for 60 minutes to 2.5mm, then warm-rolled at 600°C for 15 minutes to 1.5mm, and then cold-rolled to 0.3mm, and the sheet is subjected to primary recrystallization at 800°C and 1150°C ℃ secondary recrystallization treatment to obtain 0.3mm thick Fe-Al flakes with Gaussian texture;

3. Heat the Fe-Al flakes obtained in step (2) at 550°C for 40 minutes, and roll the Goss textured flakes with a reduction of 50-85% on a cold rolling mill, and return them to the furnace for 3 minutes each time at the beginning , when rolling to a thickness of 0.2mm, return to the furnace for 2 minutes for every 4 to 5 passes until rolling to a thickness of 0.05mm;

4. Seal the Fe-Al ultra-thin strip obtained in step (3) and heat-treat it in a box furnace or place the ultra-thin strip in a vacuum furnace with an inert gas or hydrogen protective atmosphere. The heat treatment process is carried out at 1100 ° C. Short-term annealing for 30s, followed by 1200°C heat preservation for 10h, finally obtains an extremely thin strip with a cubic texture, and the saturation magnetostriction reaches 232ppm, as shown in Figure 1.

Embodiment 4: The method for preparing Fe-Al magnetostrictive ultra-thin strip by three times recrystallization:

1. Prepare Fe ₇₈ Al ₂₂ (AlN) _0.1 (x=10-30) (the above are atomic fractions), and use the directional solidification method to obtain an alloy ingot with a <100> orientation. The alloy ingot is solidified at 1250°C for 3.4h Solution treatment, cutting the alloy ingot into 33mm slabs;

2. The slab obtained in step (1) is firstly hot-rolled at 1000°C for 60 minutes to 2.5mm, then warm-rolled at 600°C for 15 minutes to 1.4mm, and then cold-rolled to 0.29mm, and the sheet is subjected to primary recrystallization at 800°C and 1150mm ℃ secondary recrystallization treatment to obtain 0.29mm thick Fe-Al flakes with Gaussian texture;

3. Heat the Fe-Al flakes obtained in step (2) at 550°C for 40 minutes, and roll the Goss textured flakes with a reduction of 50-85% on a cold rolling mill, and return them to the furnace for 3 minutes each time at the beginning , when rolling to a thickness of 0.2mm, return to the furnace for 2 minutes for every 4 to 5 passes of rolling, until rolling to a thickness of 0.04mm;

4. Seal the Fe-Al ultra-thin strip obtained in step (3) and heat-treat it in a box furnace or place the ultra-thin strip in a vacuum furnace with an inert gas or hydrogen protective atmosphere. The heat treatment process is carried out at 1100 ° C. Short-term annealing for 30s, followed by 1200℃ for 10h, the very thin ribbons with cubic texture were obtained.

Claims (6)

1. the method that one kind prepares Fe-Ga (Al) magnetostriction strip in razor-thin using tertiary recrystallization, it is characterised in that specific steps It is as follows：

(a) directional solidification method is used to obtain the material composition of alloy pig as Fe_100-x-yGa_xM_yOr Fe_100-x-yAl_xM_yAlloy pig, X, y is atomic fraction, and surplus is iron, and solution treatment is first carried out to alloy pig, then alloy pig wire cutting is thick into 30~35mm Slab；

The Fe_100-x-yGa_xM_yIn x values be 13-30, y values are 0.01-1.0；Fe_100-x-yAl_xM_yIn x values be 10- 30, y values are 0.01-1.0；

(b) 30~90min of first 900~1200 DEG C of insulations of slab that step (a) obtains are hot-rolled down to 2~3mm, at 300~700 DEG C 10~60min warm-rollings are incubated to 1~1.5mm, 0.25~0.35mm is then cold-rolled to, 700~850 DEG C is carried out to thin slice for the first time again Crystallization and 1000~1250 DEG C of secondary recrystallization processing, obtain Fe-Ga (Al) thin slice with goss texture；

(c) thin slice that step (b) obtains is incubated 10~40 minutes at 300~700 DEG C, to goss texture thin slice on cold-rolling mill Rolled with 50~85 ﹪ drafts, initially often roll a time and melt down insulation 1-5min, it is 0.12~0.2mm to roll thickness When, often roll 4~5 passages and melt down insulation 1~3 minute, until rolling thick to 0.02~0.05mm；

(d) heat treatment after strip in razor-thin tube sealing that step (c) obtains or put strip in razor-thin is heat-treated in a vacuum furnace, it is final to obtain Strip in razor-thin with cubic texture.

2. the method for preparing Fe-Ga (Al) magnetostriction strip in razor-thin using tertiary recrystallization as claimed in claim 1, its feature It is, step (a) Fe_100-x-yGa_xM_yOr Fe_100-x-yAl_xM_yIn M be AlN, NbC, MnS, TiC, VC in one kind or more Kind.

3. the method for preparing Fe-Ga (Al) magnetostriction strip in razor-thin using tertiary recrystallization as claimed in claim 1, its feature It is, step (a) alloy pig is having for directional solidification acquisition<100>The alloy pig of orientation.

4. the method for preparing Fe-Ga (Al) magnetostriction strip in razor-thin using tertiary recrystallization as claimed in claim 1, its feature It is, step (a) solution treatment is to carry out 1~5h solution treatment to alloy pig at 1200~1300 DEG C.

5. the method for preparing Fe-Ga (Al) magnetostriction strip in razor-thin using tertiary recrystallization as claimed in claim 1, its feature It is, step (d) Technology for Heating Processing is 900~1100 DEG C of 10~60s of progress short-cycle annealing, in 1100~1250 DEG C of guarantors 10~12h of temperature.

6. the method for preparing Fe-Ga (Al) magnetostriction strip in razor-thin using tertiary recrystallization as claimed in claim 1, its feature It is, heat treatment is carried out under inert gas or hydrogen shield atmosphere in step (d) vacuum drying oven.