JPS5964734A - Co-ni magnetic alloy - Google Patents

Abstract

PURPOSE:To obtain the titled Co-Ni magnetic alloy which can be easily cold worked into a wire material at low cost, by letting a Co-Ni magnetic alloy containing the specified amounts of Co and Ni contain the specified amount of Fe. CONSTITUTION:In a Co-Ni magnetic alloy comprising Ni <=30wt%, pref. above 10wt%, and the balance mainly Co, Fe is additionally contained in an amount of 2-10%. Hence, the alloy can be cold worked into a wire material and used as a vapor deposition material for a vapor deposition-type magnetic recording tape. In order to improve its corrosion resistance, one or more of Cr <=5wt% and P <=0.1wt% may be added.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a Co--Ni magnetic alloy for vapor deposition used in the magnetic film of a magnetic recording tape. tm by cold working when forming vaporized WFI from alloy.
A continuous cotton material that has been converted to a can be used as a vapor deposition material.

Conventional magnetic recording tapes were generally made by kneading magnetic material powder such as metal oxide powder with a synthetic resin binder and coating it on the tape base material, but recently, magnetic material powder such as metal oxide powder was kneaded with a synthetic resin binder and this was coated on the tape base material. 2. Description of the Related Art Magnetic recording tapes capable of high-density recording, which are formed by forming a magnetic metal thin film on a tape base material, have been developed. As a method for forming a magnetic metal thin film on a tape base material in this way, electroless plating method or the like can be applied, but there are problems with the surface treatment of the base material, and magnetic gold tilt method is applicable. It is known that vapor deposition methods including vacuum vapor deposition and ion plating are advantageous in terms of film homogeneity, adhesion, and thin film formation speed. Among them, for example, 75-80% Co-20
A magnetic recording tape on which a vapor-deposited film of a CoNi-based magnetic alloy with a composition of ~25% Ni is formed is made of Ha.
(coercive force) and Br (residual magnetic flux density) characteristics, and is expected to be excellent as a high-density recording tape. However, when forming a deposited film as a magnetic film of a magnetic recording tape using a conventional CoNi-based magnetic alloy, there are the following problems.

In other words, since magnetic recording tape is a continuous long product,
Magnetic recording tape made by vapor deposition! When fabricating #, it is necessary to continuously feed the base tape and continuously perform vapor deposition on its surface. At this time, it is difficult to increase the length beyond a certain level unless the deposition material (i.e., CoNi-based filtration alloy material here) is continuously supplied into the deposition chamber. In order to manufacture a type magnetic recording tape, continuous supply of Vi material-saving Fl into the deposition chamber is considered essential. Generally, powdered material is used as a material for fish, but in the case of powder, it is necessary to control the atmosphere such as the degree of vacuum with high accuracy, so it is not possible to enter the K-wearing chamber from outside. Continuous supply is extremely difficult in practice.

From these points, it is considered appropriate to use a soft pillow material as the vapor deposition material and to continuously supply the wire into the vapor deposition chamber when depositing the base tape. However, conventional CoNi-based magnetic alloys have poor workability;
Since cracks will occur if cold working is carried out, it is actually difficult to form fill wires by cold working. Therefore, when a CO--Ni magnetic alloy is made into a wire rod, hot working is required. However, in the case of hot processing, equipment costs increase due to the need for a heating furnace, and running costs increase due to the energy required for heating.Moreover, pickling is required due to the eroded culm, etc. There is a problem in that the cost is significantly higher than in the case of cold working.

For these reasons, in the past, when vapor-deposited recording tapes were produced on an industrial scale using CONi-based magnetic alloys, the cost had to be high.

This invention was made in view of the above circumstances, and it improves the processability of a Co-Ni magnetic alloy that is most suitable for the vapor deposited film of a vapor-deposited magnetic recording tape, and produces a base tape of the Co-Ni magnetic alloy. To reduce the cost in industrial production of a magnetic recording tape having a CoNi-based magnetic alloy vapor deposited film by using a vapor deposition material made into a wire by cold working during vapor deposition. The purpose is to

In other words, the present inventors have conducted intensive research on CQ-Ni-based magnetic alloys, and have found that by adding Fe, the workability is significantly improved compared to conventional ones, making cold working possible. This discovery led to this invention.

Specifically, this invention applies to less than 30% Ni)
and the remainder is mainly Co (cobalt)
In Ni-based magnetic alloys, Fe (iron) is 2 to 1096
The gist of this is to add and modify the processing fi[tA″tJ.

This invention will be described in more detail below.

First, the reason for limiting the components of the Co--Ni alloy (n-type alloy) of this invention will be explained.

N; is an effective element for improving magnetic properties by increasing He (coercive force) of Co-based magnetic metals and improving squareness properties, but if added in excess of 30%, Sr
(Residual magnetic flux density) decreases, so the Ni content should be 30% or less. The lowest limit of Ni content is not particularly specified, but in order to obtain a significant N: addition effect, it must be at least 1%.
It is preferable to include the above amount.

Note that if the Ni content n is low, the workability will decrease, so the m content of e must be increased accordingly, and conversely, the m content of e must be increased.
If the content of n in e becomes excessive, the magnetic properties will deteriorate as described later. From these points of view, Ni content m is 10%
As mentioned above, J: is preferably set to 15% or more.

``e'' is an element effective in improving the workability, especially cold workability, of CoNi-based alloys, and the present inventors are the first to discover the effect of adding ``e'' to CoNi-based magnetic alloys. However, if "e" is less than 2%, a sufficient effect of improving cold workability cannot be obtained, so "e
The lower limit is 2%. On the other hand, if Fe exceeds 10%, 3
Since the magnetic properties such as r and Hc are decreased, and the decrease in [3r is particularly significant, the upper limit of Fe is set at 10%.

To explain in more detail the reason for this upper limit limitation, the present invention'? 8i etc. are various CONi-based alloy test materials (however, some have Or and P added) that have been varied from 0 to 40%.
11”e addition amount and magnetic properties of alloy (Hc and Br-
), the results shown in Figures 1 and 2 were obtained by 1q. From Figures 1 and 2, it can be seen that ``rl exceeding 010%
The magnetic properties suddenly deteriorate near 1, and then B r I + ti
``If e exceeds 10%, it will be lower than the characteristic limit of 0.5 for magnetic recording tape.Therefore, ``the upper limit of e must be 10%. In Figure 1, the workability judgment line indicates the range in which cold working was possible when cold working tests were performed on each sample material using a roller die, and the range in which cold working was possible using a roller die.
! This shows the area where the first construction was impossible due to cracks and the ulcer culm. From Figure 1, a good cold 1? It is understood that in order to improve the i-processing 11- by 1!7, it is necessary to add a large amount of Ni when the Ni content is low.

The magnetic alloy of the present invention basically contains Ni and e in the range shown in (e) above, and the balance may be substantially C0, but in addition, it may contain 5% or less in order to improve corrosion resistance. Any one or two of Or and 0.1% or less of P
You may also add shu. Even when Or or P is added in this way, the effect of adding Fe does not cause curvature.

Next, a method for producing a vapor-deposited magnetic recording tape using the Go Ni-based magnetic alloy of the present invention will be explained.
o Ni-based (magnetic alloy is melted in advance by vacuum melting and casting so that it has the above-mentioned components, and the obtained alloy material is processed into a wire rod by cold working such as wire drawing or roller die processing) .And this CONi
A C0--Ni magnetic alloy is continuously deposited on a base tape by using a vacuum evaporation method, an ion blating method, or the like, using a C0--Ni magnetic alloy wire as a deposition material (halogen source). That is, the N material is continuously fed to the vapor deposition source heating section in the vapor deposition chamber, and continuously heated by ion beam 11 irradiation, electron beam irradiation, etc. to continuously vaporize Co, Ni, and E atoms. At the same time, the base tape is continuously supplied into the deposition chamber,
A Co Ni Fe magnetic alloy may be deposited on the surface of the base tape.

The material of the base tape used in the magnetic recording tape for the above-mentioned vapor deposition is not particularly limited. For example, a plastic film having a thickness of 5 to 25 mm and made of polyester, acetate, polycarbonate, etc. is preferably used. Note that these base tapes can be used in close contact with the -C gold oxide-deposited crotch, if necessary. In order to improve 0.1-2.OJJm, especially 0.3
It is preferable to set it within the range of 1.0 to 1.0 units. At this time, 0.
If the number of households is less than 3, especially less than 0.1, sufficient records cannot be recorded.
1.0p again! If it exceeds 1, especially 2.0, the flexibility of the tape will decrease and the recording density will also decrease, which is not preferable.

A practical example of this invention will be described below.

Examples For the C0Ni-based Fli alloys having the compositions shown in the left column of Table 1, samples jlri01 to N*, 14, after vacuum melting and casting,
It was cold-worked into a wire rod by wire drawing or roller die processing. In this cold working process, 1
The right side of Table 1 shows the results of determining the cold workability of each sample by examining the occurrence of cracks when the diameter was reduced from 9.5cm to 8.6wun in a pass. Regarding the determination of cold workability, the ○ mark indicates that no cracks occurred during either wire drawing or roller die processing, and cold work was possible, and the △ mark indicates that cracks occurred only during roller die processing. The mark X indicates a case in which cracks occurred in both wire drawing and roller die processing, making cold working impossible. In addition, using the cold-worked wire rod obtained as in above) E as a vapor deposition material, a vapor deposited film was formed on the base tape according to a conventional method, and the magnetic properties of the vapor deposited film were investigated. It is also shown in the table.

In Table 1, sample M\'39 is [e is not gold-stoned, and test I! Sample No. 10 has an e-content of less than 2%, and cold workability is poor in all cases. Sample No. Q11 has an e-containing bacteria of more than 10%, In this case, the magnetic property t1 is significantly reduced.

In contrast, the other samples (1 to 8, 12 to 14) are within the scope of the present invention, and in each case, the cold workability is good and high [! ! It is clear that the mind 1111 is (''l).

As is clear from the above description, the CONi-based magnetic alloy of the present invention has poor cold workability, and therefore can be easily and inexpensively made into a wire rod by cold working. Therefore, if a CON; based magnetic alloy of the present invention is used, the cold-open processed cotton material is used as the vapor deposition amount A material, and it is continuously fed to the vapor deposition chamber to be vapor deposited on the tape base material, thereby producing CoNi based magnetic alloy. It is iJ's ability to manufacture alloy-deposited magnetic recording tapes on an industrial scale at low cost and with high productivity.

Figure 1 is a correlation diagram showing the relationship between the addition amount of e and 1c (coercive force) in various Co-Ni magnetic alloys. It is a correlation diagram showing the relationship between the addition amount and Br (residual ffi flux density).

Applicant: Nippon Musical Instruments Manufacturing Co., Ltd. Agent or Sokushi 1) Hisashi Takeshi ((J or 1 person)

Claims (1)

[Claims] [
Co-N characterized by containing 2 to 10% of e
i-based magnetic alloy.