JPH0352530B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a Fe-Ni-Si-Cr magnetic alloy with excellent magnetic properties. Fe-Ni magnetic alloys can be broadly divided into PC permalloy and PB permalloy. PC permalloy has high magnetic permeability and low coercive force, but has the disadvantages of low saturation magnetic flux density and high price.
PB permalloy has a high saturation magnetic flux density, but its magnetic permeability is lower than that of PC permalloy. Therefore, existing magnetic alloys cannot be applied to parts that require high magnetic permeability and high saturation magnetic flux density, for example. Materials having such high magnetic permeability and high saturation magnetic flux density have a wide range of uses, including shielding materials for magnetic heads and the like, and iron cores for electromagnetic force. As a result of conducting many experiments to search for materials, the present inventors discovered that the Fe-Ni-Si-Cr alloy shown below has excellent magnetic properties.
It was confirmed that this magnetic alloy is suitable for the above applications. That is, in the present invention, Ni40 to 60% by weight and Si 0.05 to
The gist of the magnetic alloy is 1.5% by weight, 0.01 to 1.5% by weight of Cr, 0.01% by weight or less of O, 0.005% by weight or less of N, and the remainder Fe and inevitable impurities. The magnetic alloy of the present invention has been used conventionally.
The maximum magnetic permeability is increased and the coercive force is lowered without impairing the high saturation magnetic flux density of PB permalloy. Its specific characteristics are shown in Table 1.

[Table] In other words, the magnetic alloy of the present invention has better maximum magnetic permeability and coercive force than conventional PB permalloy,
The saturation magnetic flux density is also comparable to PB permalloy. Also, compared to PC permalloy, it can be manufactured at a lower cost, similar to PB permalloy. As described above, the magnetic alloy of the present invention has high magnetic permeability, low coercive force, and high saturation magnetic flux density, and can be obtained at low cost, so it is an alloy suitable for various uses. The reason for limiting the composition range of the magnetic alloy of the present invention will be described below. Ni: Must be contained at least 40% by weight to ensure a saturation magnetic flux density comparable to that of PB permalloy. However, if the content exceeds 60% by weight, the saturation magnetic flux density will decrease and the cost will increase, resulting in an economic disadvantage, so the content is limited to a range of 40 to 60% by weight. Si: This is an extremely effective element for improving maximum magnetic permeability. Conventionally, the maximum permeability was increased by containing about 4% or more, but as will be described later, we have added O to 0.001% by weight or less and N 0.005% by weight
By doing the following, it was possible to increase the maximum magnetic permeability by containing 0.05% by weight or more of Si. However, since an increase in Si content lowers the saturation magnetic flux density, the upper limit was set at 1.5% in order to maintain a saturation magnetic flux density comparable to that of PB permalloy. Cr: Like Si, it is an element that improves maximum magnetic permeability. However, if the content is less than 0.01% by weight, it will have almost no effect, and if it exceeds 1.5% by weight, the maximum magnetic permeability will decrease, which is not preferable. O: Forms an oxide with additive elements such as Cr and Si, and this oxide causes a decrease in maximum magnetic permeability. Furthermore, even if this oxygen is in solid solution, it deteriorates the magnetic properties, so the content was kept to 0.01% by weight or less. This prevents Si and Cr from becoming oxides and being consumed, making it possible to achieve a maximum magnetic permeability of 70,000 or more with the above amounts of Si and Cr. N; Similar to the oxygen mentioned above, nitrogen is an additive element, i.e.
Nitride is formed with Si and Cr, and this nitride is the cause of lowering the maximum magnetic permeability. Further, even if this nitrogen is in solid solution, it deteriorates the magnetic properties, so the content was kept to 0.005% by weight or less. This results in
Prevents Si and Cr from becoming nitrides and being consumed.
We were able to achieve a maximum magnetic permeability of 70,000 or more with the above amounts of Si and Cr. In addition, the inclusion of Cr is also effective in improving the corrosion resistance of the alloy. Next, the characteristics of the magnetic alloy of the present invention will be explained in detail using examples. Example 1 A magnetic alloy having the composition shown in Table 2 was annealed at 1100° C. for 1 hour in a hydrogen atmosphere, and then subjected to measurement of magnetic properties. The results are shown in Table 3.

【table】

【table】

[Table] As is clear from Table 3, in sample materials No. 1 and No. 2 with a Si content of less than 0.05% by weight, the maximum magnetic permeability μmax is extremely low at 31900 and 21100, and the coercive force Hc (Oe) also increases to 0.129 and 0.159, which is not desirable. Also, test material No. 10 with Cr content exceeding 1.5% by weight
In this case, the saturation magnetic flux density B ₁₀ (G) is low and it is not suitable. As shown in sample material No. 13, if the content of O and N exceeds the range of the present invention, the maximum magnetic permeability will be too low and the coercive force will become large, which is not preferable. Figures 1 and 2 show Si in specimens 1 to 7.
This figure shows the change in maximum magnetic permeability depending on concentration. From Figure 2, the maximum magnetic permeability is Si concentration 0.05% by weight.
It can be seen from the above that the values are extremely high. FIG. 3 similarly shows the change in coercive force depending on the Si concentration. This figure shows that the coercive force takes a significantly low value when the Si concentration is 0.05% by weight or more. FIG. 4 similarly shows the change in saturation magnetic flux density depending on the Si concentration. This figure shows that the saturation magnetic flux density decreases linearly as the Si concentration increases. Figure 5 shows Cr in test materials 7 to 10.
This figure shows the change in maximum magnetic permeability depending on concentration. From this figure, it can be seen that the Cr concentration has a maximum value around 0.8% by weight. FIG. 6 similarly shows the change in coercive force depending on the Cr concentration. It can be seen from this figure that the coercive force decreases as the Cr concentration increases up to a Cr concentration of around 1% by weight, but increases again above that point. FIG. 7 similarly shows the change in saturation magnetic flux density depending on the Cr concentration. This figure shows that the saturation magnetic flux density decreases linearly as the Cr concentration increases. As seen in the above examples, the magnetic alloy of the present invention has a maximum magnetic permeability of 70,000 or more, a coercive force of 0.10 Oe or less,
Since it has magnetic properties with a saturation magnetic flux density of 13,000 G or more, it is a magnetic alloy suitable for parts that require high magnetic permeability and high saturation magnetic flux density.

[Brief explanation of drawings]

Figures 1 and 2 are graphs showing changes in maximum magnetic permeability depending on Si concentration, Figure 3 is a graph showing changes in coercive force depending on Si concentration, and Figure 4 is a graph showing saturation magnetic flux depending on Si concentration. Graph showing changes in density; Figure 5 is a graph showing changes in maximum permeability depending on Cr concentration; Figure 6 is a graph showing changes in coercive force depending on Cr concentration; Figure 7 is a graph showing changes in coercive force depending on Cr concentration. 3 is a graph showing changes in saturation magnetic flux density.

Claims (1)

[Claims] 1 Ni40-60% by weight, Si0.05-1.5% by weight,
A magnetic alloy consisting of 0.01 to 1.5% by weight of Cr, 0.01% by weight or less of O, 0.005% by weight or less of N, and the balance Fe and unavoidable impurities.