JPH027370B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method for manufacturing a magnetically hard FeCoMnC alloy wire. (Prior art and its problems) Patent application No. 56-154369, 56-
154370 and 56-154373, FeCoMnC-based alloys can be cold-worked and have high coercivity magnetic properties with a short and simple heat treatment after cold working. Moreover, it has a feature that the coercive force increases as the degree of cold working increases. For example, a FeCoMnC alloy wire that has been cold-drawn with an area reduction of 93% can be used at a temperature of 425℃.
After heat treatment for 60 minutes, magnetic properties with coercive force (bHc) of 800 Oe were obtained. The alloy wire rod subjected to cold wire drawing as described above has a certain curvature and is not suitable for applications requiring a straight wire rod. Therefore, it was necessary to straighten the wire with a straightening machine to make it a straight wire. However, it was observed that cracks were generated inside the FeCoMnC alloy wire that had been subjected to the above straightening. Furthermore, the above
The FeCoMnC alloy wire rod contains 0.5% by weight of C element, and the manufacturing conditions of the wire rod are as follows: The solution treatment temperature performed before cold wire drawing is 1100℃, and the area reduction rate of cold wire drawing is It was 93%. (Objective of the Invention) The present invention provides a method for manufacturing a straight FeCoMnC alloy wire without cracks inside the material. (Structure of the invention) That is, the present invention includes Co: 30 to 55% by weight, Mn: 15
A method for manufacturing an alloy wire consisting of ~27% by weight, C: 0.1~0.45% by weight, and the balance Fe, characterized by performing solution treatment at a temperature range of 800°C to 900°C before cold wire drawing. A method for producing a FeCoMnC alloy wire with Co: 30 to 55% by weight, Mn: 15 to 27% by weight, C: 0.1 to 0.45% by weight, Si: 3.6% by weight or less or V: 2.9% by weight or less Or, a method for manufacturing a wire rod containing 2.5% by weight or less of Si and V in total, with the balance being Fe, characterized by performing solution treatment at a temperature range of 800°C to 900°C before cold wire drawing. This is a method for manufacturing FeCoMnC alloy wire rod. (Detailed explanation of the structure) By adopting the above-described structure, the manufacturing method of the present invention can produce straight FeCoMnC straightened by a conventional straightening machine.
This solves the problem of cracks occurring inside the alloy wire. In the manufacturing method of the present invention, first, the solution treatment temperature is
Limited to 800℃~900℃. The reason for this limitation is 800
This is because, at temperatures below .degree. C., phases other than the austenite phase precipitate, making cold wire drawing impossible. In addition, at temperatures exceeding 900℃, straightening with a straightening machine is the same as in the case of the conventional manufacturing method of FeCoMnC alloy, which is solution-treated at 1100℃.
Cracks occurred inside the FeCoMnC alloy wire. The amount of C element added also affects the solution treatment temperature range limited above. If more than 0.45 wt.
Cracks occurred inside the FeCoMnC alloy wire. Also, when adding C element below 0.1% by weight,
The austenite phase became unstable at room temperature, and work hardening during cold wire drawing was significant, making it impossible to perform good cold wire drawing. Co 30% to 55% by weight
coercive force, residual magnetic flux density (hereinafter referred to as Br), Br/Bs, and maximum energy product (hereinafter referred to as
BHmax) has deteriorated. Therefore Co is 30
A range of 55% by weight is required. but
When Co is 30% by weight, adding more than 27% by weight of Mn will reduce the amount of magnetization, making it impractical.
For a 55 wt % alloy, adding less than 15 wt % Mn did not result in a magnetically hard alloy. Therefore, the Mn range is 15 wt% to 27
It was expressed as weight%. When V was added in an amount exceeding 2.9% by weight, it was possible to introduce the γ phase at room temperature. Furthermore, when Si was added in an amount exceeding 3.6% by weight, it was impossible to introduce the γ phase to room temperature. When both Si and V were added, an austenite phase could not be stably obtained at room temperature unless the total amount was 2.5% by weight or less. (Examples) The present invention will be described in detail below based on Examples. Table 1 shows the composition of the FeCoMnC alloy used in the examples. No. 1 to No. 7 in Table 1 are compositions of the present invention, and when the compositions were solution-treated at a predetermined temperature and then rapidly cooled, an austenite phase could be obtained at room temperature. However, in No. 8 to No. 9 in Table 1, an austenite phase was not obtained as described above, and the samples were transformed into a ferromagnetic phase. For the compositions No. 1 to No. 7 in Table 1, the alloys were heated to the solution treatment temperature shown in Table 2 and then rapidly cooled. Line processing was applied. The above-mentioned cold wire drawing process was applied.
The FeCoMnC alloy wire was straightened using a straightening machine to obtain a straight alloy wire. When the inside of the alloy wire was observed with a metallurgical microscope, it was found that cracks had formed inside the material in those heated to a solution treatment temperature exceeding 900°C and in those to which 0.45% by weight or more of C was added (No. 7). There was found. However, those that are solution-treated within the composition range of the present invention at a temperature in the range of 800°C to 900°C,

【table】

【table】

[Table] No cracks were observed. In addition, No. 1 in Table 1
~ Regarding the composition of No. 9, when solution treatment is performed at a temperature below 800°C, all the crystal structures of No. 1 to No. 9 are such that other phases, such as carbide, are precipitated in the austenite phase. Was. The coercive force and residual magnetic flux density in Table 2 are calculated for the alloy wire after straightening if there are no cracks inside the material, and for the alloy wire before straightening if there are cracks, at the heat treatment temperature shown in Table 2. The magnetic properties of the samples treated with time are shown. When an alloy with a Nn composition of 29% by weight as in alloy No. 1 in Table 1 was processed in the same manufacturing process as No. 1, the residual magnetic flux density Br was as small as 0.8 KG, which was not practical. When alloy No. 3 with a Mn composition of 13% by weight was processed in the same manufacturing process as No. 3, the coercive force Hc was as small as 310 oersted, making it impractical. The Co composition of alloy No. 5 in Table 1 is
Two types of alloys with 25 weight % and 60 weight % No. 5
When processed using the same manufacturing process, the residual magnetic flux densities Br were as small as 2.2KG and 2.1KG, respectively, making them impractical. (Effect of the invention) As a result, Co: 30 to 55% by weight, Mn: 15 to 27
Weight%, C: 01-0.45% by weight, balance consisting of Fe alloy and Co: 30-55% by weight, Mn: 15-27% by weight,
In a method for manufacturing an alloy wire rod containing Si: 3.6% by weight or less, V: 2.9% by weight or less, or a total of 2.5% or less of Si and V with respect to C: 0.1 to 0.45% by weight, and the balance being Fe, cold stretching is By applying solution treatment at a temperature range of 800℃ to 900℃ before wire processing,
It was found that even if the material was straightened using a straightening machine after cold wire drawing, no cracks were generated inside the material. Furthermore, the magnetic properties did not vary significantly due to the difference in solution treatment temperature.

Claims (1)

[Claims] 1 Co: 30 to 55% by weight, Mn: 15 to 27% by weight,
C: A FeCoMnC-based alloy in which a method for producing an alloy wire consisting of 0.1 to 0.45% by weight, the balance being Fe, is characterized by performing solution treatment at a temperature range of 800°C to 900°C before cold wire drawing. A method of manufacturing wire rods. 2 Co: 30-55% by weight, Mn: 15-27% by weight,
In a method for producing an alloy wire rod containing Si: 3.6% by weight or less, V: 2.9% by weight or less, or a total of 2.5% by weight or less of Si and V with the balance being Fe, cold A method for producing a FeCoMnC alloy wire, characterized by performing solution treatment at a temperature range of 800°C to 900°C before wire drawing.