JPS625972B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a high magnetic permeability alloy that has excellent magnetic properties and wear resistance in an alternating magnetic field, is easy to forge and process, and is suitable for a magnetic recording/reproducing head, a method for producing the same, and a magnetic recording/reproducing head. Since magnetic recording/reproducing heads such as tape recorders operate in alternating magnetic fields, the magnetic alloys used therein must have high effective magnetic permeability in high-frequency magnetic fields, and magnetic tapes must slide in contact with each other. Therefore, it is desired that the wear resistance be good. Currently, Sendust (Fe-Si
-Al-based alloy) and ferrite (MnO-ZnO-
Fe ₂ O ₃ ), but these are extremely hard and brittle and cannot be forged or rolled. Grinding and polishing methods are used to manufacture head cores, and the finished product is therefore expensive. . Sendust has a high saturation magnetic flux density, but since it cannot be made into a thin plate, its effective permeability in a high-frequency magnetic field is relatively small. Ferrite has a high effective permeability, but its saturation magnetic flux density is relatively low.
The disadvantage is that it is small, less than 5000G. On the other hand, permalloy (Ni-Fe alloy) is easy to forge, roll, and punch, making it suitable for mass production, but its major drawback is that it is soft and easily wears out. The applicants conducted research on the wear resistance of Ni-Fe alloys, and previously published
As mentioned above, Ni-Fe-Nb alloy is a magnetic alloy that is easy to forge, has excellent wear resistance, and is suitable for magnetic recording/reproducing heads. In order to increase the coercivity, magnetic tapes with high coercivity have come to be used, and along with this, magnetic alloys for magnetic heads are required to have a high saturation magnetic flux density. For this reason, even in Ni--Fe--Nb alloys, there has been a trend to reduce the amount of Nb, which is a non-magnetic additive, in order to increase the saturation magnetic flux density. However, Nb
Reducing the amount will lead to a decrease in the hardness and electrical resistance of the Ni--Fe--Nb alloy, thereby deteriorating its wear resistance and effective magnetic permeability in high-frequency magnetic fields, and is not considered a suitable method. Therefore, there is a strong demand for some improvement measures. The present invention aims to maintain superior wear resistance and effective magnetic permeability without impairing the forging workability of Ni-Fe-Nb alloys or reducing the saturation magnetic flux density as much as possible. When a small amount of nitrogen is added to Fe-Nb alloy, due to the synergistic effect of niobium and nitrogen,
That purpose was achieved. In other words, generally in high permeability alloys, non-metallic inclusions such as nitrides deteriorate the magnetic properties, and efforts are made to remove them as much as possible, but in the present invention, we actively remove trace amounts of Nb-based nitrides. The aim is to improve the wear resistance and effective magnetic permeability of Ni-Fe-Nb alloys. The present invention has a weight ratio of 70 to 86% nickel and niobium.
0.5-10%, nitrogen 0.0003-0.3%, a small amount of impurities and the balance iron, or the main components by weight are nickel 70-86%, niobium 0.5-14%, nitrogen
0.0003 to 0.3%, as subcomponents molybdenum, tungsten, tantalum, manganese, copper, cobalt each up to 7%, chromium, vanadium, titanium, germanium, gallium, indium, thallium each up to 5%, aluminum, silicon, zirconium, Less than 3% each of hafnium, rare earth elements, and white metal elements, beryllium, tin,
Consists of less than 2% each of antimony, less than 1% of boron, a total of 0.01 to 7% of one or more types, a small amount of impurities and the balance iron, saturation magnetic flux density 5000G
The present invention relates to a high permeability magnetic alloy that has the above properties, has excellent wear resistance and effective magnetic permeability, and can be easily forged and used for magnetic recording/reproducing heads and the like.
Furthermore, the present invention relates to a magnetic recording/reproducing head with excellent wear resistance manufactured using the above-mentioned high magnetic permeability alloy for the case and core. The present invention will be explained in detail below. To produce the alloy of the present invention, the main components, 70 to 86% nickel, 0.5 to 10% niobium, and an appropriate amount of the balance iron, were first melted in a non-oxidizing atmosphere or in a vacuum using a suitable melting furnace. After that, add a small amount of a suitable deoxidizing agent or desulfurizing agent to remove as much impurity as possible, and then add molybdenum,
7% or less each of tungsten, tantalum, manganese, copper, and cobalt; 5% or less each of chromium, vanadium, titanium, germanium, gallium, indium, and thallium; each of aluminum, silicon, zirconium, hafnium, rare earth elements, and platinum metal elements 3% or less, beryllium, tin,
A total amount of 0.01 to 7% of one or more types of antimony (2% or less) and boron (1% or less) are added and sufficiently stirred to produce a compositionally uniform molten alloy. Next, an appropriate amount of nitrogen is added to the molten alloy by injecting gases such as N ₂ and N ₃ H into the furnace to adjust the pressure, or by adding an appropriate amount of nitride as an alloy component. Thereafter, this is poured into a mold of an appropriate shape and size to obtain a sound ingot, which is then subjected to forming processes such as hot forging and cold rolling at high temperatures to obtain the desired shape, such as thickness. Build a thin plate with a thickness of 0.1mm. Next, punch out a piece of the desired shape and size from the thin plate, and heat it in hydrogen, other suitable non-oxidizing atmosphere, or vacuum at a temperature higher than the recrystallization temperature, that is, about 600℃ or higher, especially 800℃.
Heating for 1 minute or more at a temperature below the melting point, then at an appropriate rate depending on the composition, e.g. 100°C/sec.
Cool at 1°C/hour. Depending on the composition of the alloy, this may be further reheated to a temperature of approximately 600°C or below (temperature below the ordered lattice-irregular lattice transformation point), particularly 200 to 600°C for 1 minute or more, and then cooled to reduce the saturation magnetic flux. A high permeability magnetic alloy with a density of 5000G or more and excellent wear resistance can be obtained. Cooling from the above solution temperature to a temperature above the ordered-irregular lattice transformation point (approximately 600°C) shows that there is no significant difference in the magnetic properties obtained whether the cooling is rapid or gradual; The following cooling rates have a significant effect on magnetism. In other words, from the temperature above this transformation point
By cooling to room temperature at an appropriate rate corresponding to the composition of 100° C./sec to 1° C./hour, the regularity of the ground can be appropriately adjusted and excellent magnetism can be obtained. If the material is rapidly cooled at a rate close to 100° C./second among the above cooling rates, the degree of order decreases, and if it is cooled any faster, the degree of order does not proceed, and the degree of order decreases further, resulting in deterioration of magnetism. However, when an alloy with a low degree of order is reheated to 200 to 600 degrees Celsius, below its transformation point, and cooled, ordering progresses and the degree of order becomes moderate, improving magnetism. On the other hand, if it is slowly cooled from a temperature above the above-mentioned transformation point at a rate of, for example, 1° C./hour or less, ordering will proceed too much and the magnetism will decrease. Next, examples of the present invention will be described. Example 1 Alloy number 13 (composition Ni=80.3%, Nb=5.0%, N
= 0.010%, remainder Fe) To prepare the sample, first, a total weight of 800 g was placed in an alumina crucible, melted in a high frequency induction furnace in a vacuum, and then thoroughly stirred to form a homogeneous molten alloy. Next, nitrogen gas was injected into the furnace, the pressure was adjusted to 1 × 10 ^-1 Torr, and the pressure was maintained for 10 minutes. This was then injected into a mold with holes of 25 mm in diameter and 170 mm in height, and the resulting ingot was It was forged at 1000℃ into a plate approximately 7mm thick. Further, it is hot-rolled to a thickness of 1 mm between approximately 600 and 900°C, then cold-rolled at room temperature to form a thin plate of 0.1 mm. Then, an annular plate with an outer diameter of 45 mm and an inner diameter of 33 mm and the core of the magnetic head are punched out. Ta. Next, these were subjected to various heat treatments shown in Table 1, and the annular plate was used to check the magnetic properties and hardness, and the core was used to manufacture _a magnetic head. The amount of wear after running was measured and the results shown in Table 1 were obtained.

[Table] Example 2 Alloy number 74 (composition Ni=79.8%, Nb=7.0%, Mn
= 2.5%, N = 0.013%, balance Fe) To make the sample, first nickel, iron, and niobium were used.
780g was placed in an alumina crucible and melted in a high-frequency induction electric furnace in a vacuum. After filling the furnace with argon gas, a manganese-nitrogen alloy (8% nitrogen) was melted.
(containing) was added and stirred well to obtain a homogeneous molten alloy. The subsequent manufacturing steps are the same as in Example 1. The samples were subjected to various heat treatments and the properties shown in Table 2 were obtained.

[Table] Next, Table 3 shows that after heating in hydrogen at 1150°C for 2 hours, cooling from 600°C to room temperature at various rates, or further heating at a temperature below 600°C, The properties of representative alloys measured at room temperature are shown.

【table】

[Table] Next, the effect of adding nitrogen to the alloy of the present invention will be described in detail with reference to the drawings. Figure 1 shows 80.3%Ni-
The relationship between the amount of N, saturation magnetic flux density, effective magnetic permeability, hardness, and amount of wear is shown for the Fe-5%Nb-N alloy. Generally, as the amount of nitrogen increases, the hardness increases significantly, and at the same time the amount of wear decreases significantly.
In particular, the effect of adding a small amount of nitrogen is extremely large. Further, in general, the addition of nitrogen has a great effect of increasing the effective magnetic permeability in an alternating magnetic field that operates a magnetic recording/reproducing head, especially in a high frequency magnetic field. But nitrogen
It can be seen that if the content exceeds 0.3%, forging and processing become difficult, and the magnetic properties become unsuitable as a magnetic alloy for magnetic heads. Figure 2 shows 80.3%Ni-Fe-Nb alloy and nitrogen at 0.010%
This graph shows the relationship between the amount of niobium, hardness, and wear amount for the 80.3%Ni-Fe-Nb%-0.010%N alloy, which shows that the effect of nitrogen addition increases significantly as the amount of niobium increases. . Figure 3 shows No. 13 (80.3%Ni-Fe-5.0%Nb-0.01
%N), No.36 (79.6%Ni-Fe-6.3%Nb-0.003%
N-2.0%Mo), No.60 (74.5%Ni-Fe-3.0%Nb-
0.009%N-5.0%Ta) and No.128 (81.5%Ni-
Fe-3.5%Nb-0.013%N-3.0%Cr) alloys
This graph shows the relationship between heating time and effective magnetic permeability when heated at 1150°C and then cooled at a rate of 400°C/hour, showing that each alloy has its own optimal heating time. Figure 4 shows No.13, No.36,
This graph shows the relationship between the cooling rate and effective magnetic permeability when each alloy No. 60 and No. 128 is heated at 1150℃ for an appropriate time and then cooled from a temperature above the regular-irregular lattice transformation point. It can be seen that each alloy has its own optimal cooling rate. Figure 5 is No. 13,
After heating the alloys No. 36, No. 60 and No. 128 at 1150℃ for an appropriate time, they were cooled at a rate of 400℃/hour from a temperature above the ordered-irregular lattice transformation point, and then the ordered-irregular lattice alloys were heated at a rate of 400℃/hour. This shows the relationship between reheating time and effective magnetic permeability when reheated at an appropriate temperature below the transformation point, and it can be seen that each alloy has its own optimal reheating temperature and reheating time. Such high hardness and improved wear resistance of the alloy of the present invention are due to the effect of niobium, which causes solid solution hardening of the base of the Ni-Fe alloy, but when nitrogen is added to this, nitrogen atoms enter between the lattices and harden the base. It is thought that as it hardens further, strong niobium-based nitrides, nickel-based nitrides, iron-based nitrides, etc. are finely precipitated on the ground, causing further hardening. In addition, these fine nitride precipitations divide the magnetic domain and increase the domain wall, which relatively reduces the movement speed of the domain wall in an alternating magnetic field, which reduces eddy current loss and provides a large effective magnetic permeability. It is considered that the Furthermore, Mo, W, Ta, added as subcomponents,
Mn, Cu, Co, Cr, V, Ti, Ge, Ga, In, Tl,
Al, Si, Zr, Hf, rare earth elements, platinum group elements,
Be, Sn, Sb, B, etc. have the effect of increasing the specific electrical resistance of the alloy of the present invention, Co is effective in increasing the saturation magnetic flux density, and W, Ta, V,
Ti, Ge, Ga, In, Tl, Al, Si, Zr, Hf, rare earth elements, platinum group elements, Be, Sn, Sb, B, and the like are highly effective in improving the wear resistance of the alloy of the present invention. These subcomponents also form nitrides, which improve the effective permeability and wear resistance as described above. Since the alloy of the present invention has a saturation magnetic flux density of 5000G or more, it is not only suitable as a magnetic alloy for magnetic heads, but also has a large effective magnetic permeability, high hardness,
It has excellent wear resistance and good workability.
It is also very suitable as a magnetic material for use in magnetic recording/reproducing heads for VTRs and computers, as well as ordinary electrical equipment. Next, in the present invention, the composition of the alloy is changed from Nickel 70 to
86%, niobium 0.5-10%, nitrogen 0.0003-0.3%, and the balance iron, and the elements added to this are molybdenum, tungsten, tantalum, manganese,
7% or less each of copper and cobalt, 5% or less each of chromium, vanadium, titanium, germanium, gallium, indium, and thallium, 3% or less each of aluminum, silicon, zirconium, hafnium, rare earth elements, and platinum group elements, beryllium, 2% or less each of tin and antimony, and 2% or less of boron, total of 0.01 or more
The reason for limiting it to 7% is that, as is clear from Figures 1 and 2 of Table 3 of Examples, the saturation magnetic flux density in that composition range is 5000G or more, the effective magnetic permeability and hardness are high, and the wear resistance is excellent. , and has good workability, but if the composition is outside this range, the saturation magnetic flux density will be less than 5000G, the effective magnetic permeability and hardness will be low, wear will be large, and machining will be difficult.
This is because it is unsuitable as a material for magnetic recording/reproducing heads. That is, when niobium is less than 0.5% and nitrogen is less than 0.0003%, the effect of addition is small, when niobium exceeds 10%, the saturation magnetic flux density becomes 5000G or less, and when nitrogen exceeds 0.3%, forging becomes difficult. In addition to this, the subcomponents are 7% molybdenum, 7% tungsten, 7% manganese, and 7% copper.
%, chromium 5%, vanadium 5%, titanium 5%,
Germanium 5%, gallium 5%, indium 5
%, thallium 5%, aluminum 3%, silicon 3
%, hafnium 3%, rare earth elements 3%, and platinum group elements 3%.
This is because adding more than 2% Co, 2% tin, 2% antimony, and 1% boron makes forging or processing difficult, and adding more than 7% Co reduces the effective magnetic permeability. Furthermore, as is clear from Table 3, Ni―Fe―
Adding any of the subcomponents to the Nb-N alloy increases the effective magnetic permeability, increases the hardness, and improves the wear resistance, so the addition of these subcomponents has the same effect. It can be considered as an ingredient. Rare earth elements consist of scandium, yttrium, and lanthanum-based elements, but their effects are exactly the same; platinum group elements consist of platinum, iridium, ruthenium, rhodium, palladium, and osmium, and their effects are exactly the same. It is. Note that carbon and oxygen increase hardness and improve wear resistance, so it is effective to add up to 0.1% of each without impairing workability and magnetic properties.
It may be contained in the alloy of the present invention.

[Brief explanation of the drawing]

Figure 1 is a characteristic diagram showing the relationship between nitrogen content, effective magnetic permeability, saturation magnetic flux density, hardness, and wear amount of 80.3%Ni-Fe-5%Nb-N alloy, and Figure 2 is a characteristic diagram showing the relationship between nitrogen content and effective magnetic permeability, saturation magnetic flux density, hardness, and wear amount of 80.3%Ni-Fe-5%Nb-N alloy.
Fe-Nb alloy and 80.3%Ni-Fe-Nb-0.010%
A characteristic diagram showing the relationship between the amount of niobium, hardness, and wear amount of N alloys. Figure 3 shows No. 13, No. 36, No. 60, and No. 3.
After heating each alloy of 128 at 1150℃, 400℃/
Figure 4 is a characteristic diagram showing the relationship between heating time and effective magnetic permeability when cooling at the same speed as No. 13, No. 36, and No. 36.
Figure 5 is a characteristic diagram showing the relationship between cooling rate and effective permeability when alloys No. 60 and No. 128 are heated at 1150°C for an appropriate time and then cooled from a temperature above the regular-irregular lattice transformation point. After heating No. 13, No. 36, No. 60 and No. 128 alloys at 1150℃ for an appropriate time,
FIG. 2 is a characteristic diagram showing the relationship between reheating time and effective magnetic permeability when cooled at a rate of 400° C./hour and then reheated at an appropriate temperature below the regular-irregular lattice transformation point.

Claims (1)

[Claims] 1. Nickel 70-86%, niobium 0.5-0.5% by weight
10% nitrogen, 0.0003 to 0.3% nitrogen, a small amount of impurities, and the balance iron, and is characterized by having a saturation magnetic flux density of 5000G or more. 2 Nickel 70~86%, niobium 0.5~
10%, nitrogen 0.0003 to 0.3%, a small amount of impurities and the balance iron as the main components, and minor components of molybdenum, tungsten, tantalum, manganese, copper, cobalt each of up to 7%, chromium, vanadium, titanium, germanium, gallium. , 5% or less each of indium, thallium, 3% or less each of aluminum, silicon, zirconium, hafnium, rare earth elements, platinum group elements, beryllium, tin,
A wear-resistant material for a magnetic recording/reproducing head characterized by being made of an alloy containing 0.01 to 7% of one or more types, each containing 2% or less of antimony and 1% or less of boron, and having a saturation magnetic flux density of 5000G or more. High magnetic permeability alloy. 3 Nickel 70~86%, niobium 0.5~ by weight
After heating an alloy consisting of 10% nitrogen, 0.0003 to 0.3% nitrogen, a small amount of impurities, and the balance iron in a non-oxidizing atmosphere or in a vacuum at a temperature of 600°C or higher and lower than the melting point for at least 1 minute or more depending on the composition, Rule - 100 from temperature above irregular lattice transformation point
A method for producing a wear-resistant high permeability alloy for a magnetic recording/reproducing head, which comprises cooling to room temperature at an appropriate rate corresponding to the composition of the alloy. 4 Nickel 70~86%, niobium 0.5~ by weight
An alloy consisting of 10% nitrogen, 0.0003 to 0.3% nitrogen, a small amount of impurities, and the balance iron is heated in a non-oxidizing atmosphere or in vacuum at a temperature above 600°C and below the melting point for an appropriate time corresponding to the composition for at least 1 minute and up to 100 hours. After heating, it is cooled from a temperature above the ordered-disordered lattice transformation point to room temperature at an appropriate rate corresponding to the composition of 100°C/sec to 1°C/hour, and then cooled to room temperature at a temperature below the ordered-disordered lattice transformation point. 1. A method for producing a wear-resistant high permeability alloy for a magnetic recording/reproducing head, which comprises reheating at a temperature in a non-oxidizing atmosphere or in a vacuum for at least one minute for an appropriate time corresponding to the composition, and cooling. 5 Nickel 70-86%, Niobium 0.5-0.5% by weight
10%, nitrogen 0.0003 to 0.3%, a small amount of impurities and the balance iron as the main components, and minor components of molybdenum, tungsten, tantalum, manganese, copper, cobalt each of up to 7%, chromium, vanadium, titanium, germanium, gallium. , 5% or less each of indium, thallium, 3% or less each of aluminum, silicon, zirconium, hafnium, rare earth elements, platinum group elements, beryllium, tin,
An alloy containing 0.01 to 7% of one or more of antimony and boron, each of which is 2% or less.
After heating in a non-oxidizing atmosphere or vacuum at a temperature of 600℃ or higher and lower than the melting point for at least 1 minute or more for an appropriate time depending on the composition, it is heated at a temperature of 100℃/second to 1℃/second from the regular-irregular lattice transformation point or higher. A method for producing a wear-resistant high permeability alloy for magnetic recording/reproducing heads, which is characterized by cooling to room temperature at an appropriate rate corresponding to the composition at the time. 6 Nickel 70~86%, niobium 0.5~ by weight
10%, nitrogen 0.0003 to 0.3%, a small amount of impurities and the balance iron as the main components, and minor components of molybdenum, tungsten, tantalum, manganese, copper, cobalt each of up to 7%, chromium, vanadium, titanium, germanium, gallium. , 5% or less each of indium, thallium, 3% or less each of aluminum, silicon, zirconium, hafnium, rare earth elements, white metal elements, beryllium, tin,
An alloy containing a total of 0.01 to 7% of one or more types, each containing 2% or less of antimony and 1% or less of boron, is heated for at least 1 minute in a non-oxidizing atmosphere or in vacuum at a temperature of 600°C or higher and lower than the melting point. After heating for an appropriate time corresponding to the composition (100 hours or less), cooling from a temperature above the ordered-disorder lattice transformation point to room temperature at an appropriate rate corresponding to the composition between 100℃/sec and 1℃/hour. Wear resistance for magnetic recording and reproducing heads is further characterized by reheating the head at a temperature below the ordered-disorder lattice transformation point in a non-oxidizing atmosphere or in vacuum for at least 1 minute for an appropriate time corresponding to the composition, and cooling. Manufacturing method for high permeability alloys. 7 Nickel 70~86%, niobium 0.5~
1. A magnetic recording/reproducing head comprising an alloy comprising 10% nitrogen, 0.0003 to 0.3% nitrogen, a small amount of impurities, and the balance iron, and has a saturation magnetic flux density of 5000G or more. 8 Nickel 70~86%, niobium 0.5~ by weight
10%, nitrogen 0.0003 to 0.3%, a small amount of impurities and the balance iron as the main components, and minor components of molybdenum, tungsten, tantalum, manganese, copper, cobalt each of up to 7%, chromium, vanadium, titanium, germanium, gallium. , 5% or less each of indium, thallium, 3% or less each of aluminum, silicon, zirconium, hafnium, rare earth elements, platinum group elements, beryllium, tin,
1. A magnetic recording/reproducing head comprising an alloy containing 0.01 to 7% of one or more types, each containing 2% or less of antimony and 1% or less of boron.