DE2244925B2 - Use of a cobalt-nickel-iron alloy as a semi-hard magnetic material - Google Patents

Description

The invention relates to the use of an alloy as a semi-hard magnetic material.

In general, magnetic materials used in switching elements or semi-permanent magnetic Storage devices are used that have the following properties:

1. Both the saturation magnetic flux density (Bs) and the remanent magnetic flux density (Br) are large.

2. The square hysteresis loop has a high square ratio [BrJBs] and a large "fill factor". The expression "fill factor" results from the formula

where (BH) _{max is} the product of the maximum magnetic energy and Hc is the coercive force.

3. The coercive force (Hc) is in the range between 10 and 50 Oe. In particular, the magnetic materials used in switching elements such as reed switches should also have the following properties.

4. Even if the magnetic materials are diffused or melted down If the glass is exposed to a high temperature, this high temperature will result in the desired magnetic remanence properties are not impaired.

5, The coefficient of thermal expansion of the magnetic Materials isl essentially the same as that of the Giasmateriais to choose between these two Materials to ensure a good seal.

6. The plastic deformability is excellent; That is, the materials can easily be made into the desired Shape or size, such as B. a thin line rod with a diameter ν "νπ the Size of a millimeter can be deformed.

Several cobalt-iron alloys have already become known as semi-hard magnetic materials. One of these materials, which consists of an alloy of 48% iron, 48% cobalt, 3.5% vanadium and 0.5% manganese is described in the journal "Bell Laboratories Record", p. 257, June 1965. In the Journal of Applied Physics, p. 1268, February, Vol. 39, 1968, there is one Permanent magnet alloy with low magnetostriction is described, which consists of 82% cobalt, 12% iron and 6% gold. So far, however, no semi-hard magnetic materials have become known, all of the above requirements meet.

By the German Auslegeschrift! 239 107 is an iron-nickel-cobalt-based alloy has become known that contains small amounts of titanium, niobium and contains tantalum individually or together, but either NICB or tantalum must be present. This alloy is characterized in the hardened state by one of the temperature essentially independent modulus of elasticity and serves as a material for objects such as springs and vibration elements, where the thermoelastic coefficient should remain constant over a wide range.

When looking for a semi-hard magnetic material that has the properties listed above and particularly an excellent squareness ratio and curve fill factor has, it was found that on the basis of the known alloy with corresponding Can win the composition and treatment of the desired semi-hard magnetic material.

The invention is characterized by the use of an alloy consisting of (a) cobalt, (b) iron, (c) nickel and (di) niobium or (d ₂ ) niobium and at least one metal from the group consisting of tantalum and titanium. Vanadium, zirconium, molybdenum, chromium, tungsten, with the proviso that the weight ratio of (a) cobalt to (b) iron is in the range from 3: 2 to 1: 2 and the weight ratio of (c) nickel to (b) iron in the range from 1: 1 to 1: 3 and the proportion of (d,) or (d ₂ ) is 1 to 5 percent by weight of the total alloy that has been age-hardened at 600 to 900 ° C and then cold-worked by at least 75%, as a semi-hard magnetic material.

The alloy materials listed above may contain a trace of impurities which may occur during got into the alloy during the manufacturing process. You can also use deoxidizing agents or desulfurizing agents, such as manganese, magnesium, calcium, aluminum or silicon, in the amount required to fulfill their purpose. in the in general, the proportion of deoxidizing agents or desulfurizing agents is below 1 percent by weight.

The presence of niobium in the alloy nuierial has a great effect on an increase in the coercive force of the alloy, the proportion exceeds but 5 percent by weight of niobium, then the magnetic flux density, i.e. H. the magnetic In- ί production, the alloy obtained, and the processability the alloy is significantly deteriorated. If, on the other hand, the niobium content is less than I weight percent, then the EITect of increasing the coercive force is too small to be a practical ι ο To have use.

Part of the niobium contained in the alloy material can be replaced by one or more other metals. that perform a similar function are replaced. These metals are e.g. B. tantalum, titanium, vanadium, zirconium, molybdenum, chromium. Tungsten and the like. The amount of these metals used in addition to niobium is preferably selected so that the weight ratio of these metals to niobium is below 30:70. If the weight ratio is not less than 30 to 70, then the coercive force of the alloy is not increased as much as is the case when only niobium is used.

The amount of cobalt is chosen so that the weight ratio of cobalt to iron is in the range from 3: 2 to 1: 2, preferably between 3: 2 and 2: 3, but most preferably approximately 1: 1. If the weight ratio is within this range, then the alloy material is superior in its magnetic properties, in particular the magnetic flux density (A ₁₀₀ ).

The nickel content is chosen so that the weight ratio of nickel to iron is in the range between 1: 1 and 1: 3. If the weight ratio of nickel to iron is below 1: 3, it is difficult. carry out the desired cold processing. On the other hand, if the weight ratio is greater than 1: 1. then the saturation magnetization (<r _s ) of the alloy material is too low. With a view to the desired coefficient of thermal expansion of the alloy material, the weight ratio of nickel to iron is preferably between 2: 3 and 1: 3.

The semi-hard magnetic properties of the alloy material, especially the squareness ratio (BrZB ₁₀₀ ) and the curve fill factor

The availability of the alloy material is not improved and it is difficult to achieve the desired reduction in area during cold working. Optimal results are achieved when the annealing process is carried out at a temperature between 600 and 900 ° C is carried out. This makes the squareness ratio and the curve fill factor noticeable improved.

The alloy material treated in this way is preferably subjected to a final heat treatment or subjected to a thermal aftertreatment at a temperature below 800 ° C, exceeds the temperature 800 ° C, then the coercive force is below 10 Oe.

The invention is illustrated in more detail by means of examples.

example 1

Mixtures of cobalt, iron, nickel and niobium in the ratio given in Table I with traces of silicon were made up of the five metal materials feces ",: t, electrolytic iron. Nickel, ferroniobium and silicon. Each of the mixtures was produced in melted in a crucible in vacuum. The melt was then formed into an ingot. The ingot was processed by means of a forging press at a temperature of 1100 "C. Thereafter, the ingot was cold drawn by means of a forging press, a draw bench and a wire drawing machine to form a guide rod with a diameter of 0.6 mm. During the reduction in cross-section, annealing treatments at temperatures between 1000 and HOO ⁰ C were inserted at suitable time intervals. The final reduction in area was 92%. The expression "final reduction in cross-section" (in%) is given by the formula

defined, where d _x and d ₂ mean the diameter of the rod before cold deformation and of the rod after cold deformation, respectively.

Table ΐ
Composition of the alloy in percent by weight

HBH) ^ JBr-Hc)

Sample no.

must be trained using suitable procedural steps. In order to be suitable for use in accordance with the application, the alloy material must be subjected to an annealing treatment at a temperature between 600 and 900 ° C. and cold working with a cross-sectional reduction of not less than 75%. In general, the cold working is carried out gradually until the reduction in area has reached 75% or more. one or more annealing treatments at a temperature of not less than 600 ^° C. being inserted at suitable time intervals between the deformation steps.

If the reduction in cross section is below 75%, then both the coercive force (Hc) and the magnetic induction (β | _O o) of the alloy material obtained are low. If the annealing treatment is also carried out at a temperature below 600 ^° C., then the plastic processing-SH-001 (control) ...
SH-002 (control) ..
SH-003 (invention) ...
SH-004 (invention). ..

I Co

44
47
39

Fe

46
43

35
38

Ni Nh 5 3 10 3 15th 3 20th 3

Among the four alloy materials given in Table I, the two alloys could be SH-001 and SH-002 cannot be processed into a conduction tab because of their hardening during forging.

The two rods SH-003 and SH-004 were

fto finally a final annealing treatment. ie subjected to curing at different temperatures. In Fig. I is the dependence of the magnetic properties of the alloys SH-003 and SH-004 on or, r temperature of the hardening

In Fig. 1 the temperature of the final annealing treatment is shown in degrees Celsius on the abscissa and the magnetic induction (B _1n J in Kilngauss for a magnetic field on the ordinate

of 100 Oe, the specific saturation magnetization [n,) in electromagnetic units and the coercive force (Hc) in Oe.

As shown in FIG. 1 shows, the saturation magnetization (σ,) is only slightly or not dependent on the curing temperature, i.e. h “it remains almost constant over the entire temperature range. The coercive force (Hc) varies up to almost 700 ^° C. also only slightly as a function of the temperature. The magnetic inductions (ß ₁₀ o) are large in a temperature range above about 600 ^{0 C.}

Example 2

It was made using appropriate amounts of cobalt, electrolytic iron, and nickel Ferroniobium and a trace amount of silicon in the same way as described for Example 1, Conductor wires with a diameter of 0.6 mm with the composition given in the tables manufactured.

Table II
Composition of the alloy in percent by weight

The F i g. 2 to 6 show the dependence of the magnetic properties on the niobium content in percent by weight in the alloys in the event that the conductor rods were subjected to an aging treatment in vacuum for 1 hour at temperatures of 600 ° C. (curve 1) and 700 ^° C. (curve 2) . In these figures, the curves labeled AD illustrate the data of the wire rods before the aging treatment.

The following facts can be gleaned from these figures:

The coercive force (Hc) increases, as shown in FIG. 4 shows, with an increase in niobium content. The specific »» saturation magnetization (σ,) takes, like F i g. 2 shows, with an increase in niobium content. The magnetic induction (ßjoo) is the final annealing at temperatures between 600 and 700 ⁰ C subjected to lead rods in comparison to the line of the rods prior to the final annealing is remarkably high, as shown in F i g. 3 emerges. Both the squareness ratio (BtJB ₁₀₀ ) and the curve fill factor

Sample no. Co Fe "Ί
Ni SH-005 (control) .... 40 40 20th SH-006 (invention) .... 40 39 20th SH-007 (invention) .... 38 39 20th SH-008 (invention) .... 38 3C 20th SH-009 (invention) 38 37 20th

before aging treatment. This is evident from the FIGS. 5 and 6.

F i g. 7 shows the dependence of the coefficient of thermal expansion (u) on the niobium content. As can be seen from this figure, the coefficient of thermal expansion of the wire rod falls sharply with increasing niobium content before hardening. In contrast to this, the coefficient of thermal expansion (α) of the line rod according to the

ίο Aging treatment at a temperature of 7 (X) C with a niobium content in the range between a very small percentage to approximately 5% an almost constant value, ie almost the value 100 · 10 ⁷ .

In this example, only the alloy materials are in a weight ratio of cobalt to Iron of approximately 1: 1 shown. It was found, however, that similarly good results are obtained when the weight ratio is varied in the range between 3: 2 to 1: 2.

Example 3

It was made from electrolytic iron, cobalt. Nickel and ferroniobium are a mixture of metals

of 39 percent by weight iron, 38 percent by weight cobalt, 20 percent by weight nickel and 3 percent by weight Niobium. The mixture was melted in vacuo and then into an ingot shaped. The ingot was hot worked at a temperature of 1100.degree. C. by means of a forging press. Then the ingot was made using a forging press, a drawing bench and a wire drawing machine One to seven wire rods with a diameter of 0.6 mm each cold formed. While the cross-section

Reduction was made by annealing treatments at tem y «: i atures from 1000 to HOO ⁰ C in suitable zones! aanden inserted. The final incandescent bulb, ie the annealing immediately before the first cold draw, was carried out at a temperature of! ""> C

executed. The final cross-sectional dimension of the seven lead bars is indicated in Table III at ».. ·: -Vn.

Table III

Sample no.

(HBH) _n JBr-Hc)

SH-010
SH-011
SH-Ol 2
SH-013
SH-014
SH-Ol 5
SH-016

Final
Cross-sectional approval

0
30th
51
64
75
92
97

are high at a niobium content in the range of a very small percentage up to approximately 5%, and the squareness ratio and the curve fill factor of the aging treatment at temperatures between 600 and 700 ⁰ C subjected to lead rods are higher than those of the lead rods Finally, the cold-drawn Leüunesstabe in the in were cured different temperatures indicated in Tables IV and V. The dependence of the coercive force (Hc) in Oe and the magnetic induction (B ₁₀₀ ) of the conductor rods produced in this way on the final area reduction in percent and the aging temperature is illustrated in Tables IV and V, respectively

r c

7 8

Table IV

Coercive force (Hc) in Oe Temperature of the final annealing treatment: HOO'C

Aiishiirtiings-
lernfieniliir
ι. · T O «> F.mlgiilligc f
SI Jiicr.schnillsvcrmi
M. change in%
75 92 97 ,1 /; , 0.5 I I 19th _M. 27 31 28 400 0.5 15th 23 30th 34 41 39 600 ... 0.5 15th 2! 25th 29 31 29 700 0.5 Il 18th 23.5 25th 26th 24.5 800
900 0.5
0.5 4.3
0.5 8th 9.5
0.8 10
1 Ul NJ 10.5
1.5

Table V

Magnetic induction Iß ,,,,,) in kilogauss Temperature of the final annealing treatment: 1100 ° C

Aiisharninjis-
lc temperature
in C
AD η
16.5 iOO
600 16.5
16.5 ⁷ IX) 16.5
16.5
16.5 ■ «Χ)

linilgiilligc cross-section reduction in

M)

7.2

6.8

7.4

10.0

15.0

15.0

6.6

6.2

7.6

10.5

14.4

15.9 64

6.2

6.7

8.4

11.4

14.4

16.0

g in 'ί 92 97 75 9.0 10.0 7.2 11.6 12.1 7.4 14.5 16.1 10.0 15.0 15.6 12.6 15.3 15.4 14.6 16.0 16.0 16.0

The F i g. 8 and 9 graphically represent the data of Tables IV and V. In these figures, the curves marked with the reference numerals 1, 2, 3, 4 and 5 indicate the values of the temperatures at 400, 600, 7 (Xl XiX) and respectively. 900 "C. In Figures 8 and 9 and in Tables IV and V, AD denotes data of a wire rod which was manufactured in the same way as the other wire rods, but was not subjected to curing.

From the tables and the figures it can be seen that both the magnetic induction (β, _O o> and the coercive force (Wc) of the conductor rods subjected to a final annealing treatment at a temperature of IKIOT with an increase in the final cross-section reduction in the range of not less than 75% increase.

Example 4

The procedure of Example 3 was repeated 4s wherein the final annealing was carried out at temperatures between 700 and 9 ck) ⁰ C and the definitive Querschnktsverminderung while maintaining the other conditions as shown in Tables VI to IX, was varied. The coercive force (Hc) and the magnetic induction (B ₁₀₀ ) of the conductor rods produced in this way are given in Tables VI to DC.

Table VI

Coercive force [Hc) in Oe Temperature of the final annealing treatment: 700 "C

Final
Cross section reduction

75
92
97

AD

55
44
36

4Of)

47 46 41 Aiishardening temperature in 'C

500

37 38 34

600 700 800 900 28 20th 10 2.5 29 22nd 9 3 33 21 11

Table VII

Magnetic induction (B ₁₀₀ ) in kilogauss. Temperature of the final annealing treatment: 700 ° C

Final AD 400 Closing temperature 500 fix) in C 7 (X) 8 (X) 9 (X) Cross-sectional
reduction
in % 8.8 12.4 14.0 15.0 15.5 15.2 16.0 75 10.0 12.0 14.3 15.5 15.7 15.4 15.4 92 11.0 13.6 14.5 17.2 17.0 15.8 16.1 97

Table VIII

Coercive force (Wc) in Oe Temperature of the final annealing treatment: 900 ° C

Final
Cross section
reduction
in % AD 400 Aushü
5 (X) curing temperature
600 in C
7 (X) 800 900 75 37 46 42 31 26th 6th 2.5 92 39 51 41 31 24 9 2.5 97 34 44 54 26th 22nd 10 2.5

Table IX

Magnetic induction [B _{Q0 ] in kilogauss temperature of the final annealing treatment: 900 ° C

Final AD 400 Curing temperature 500 600 in C 70 () 800 900 Cross-sectional 7.5 8.2 8.8 11.2 14.1 15.3 15.5 reduction 9.2 12.0 14.0 14.8 14.4 15.6 15.5 in % 10.1 12.4 13.4 16.5 15.4 15.4 15.4 75 92 97

From Tables VI and VIII it can be seen that the coercive force (Wc) reaches a maximum at a curing temperature of approximately 400 ° C and then decreases with increasing aging temperature. The coercive force (Wc) lies at a curing temperature above 800 ° C below about 10 Oe. Magnetic induction (ßioo) increases in the generally with an increase in the final reduction in size and the curing temperature.

Example 5

The procedure according to Example 3 was repeated, the final annealing treatment at 700, 900 and 1100 ° C and the hardening treatment at 600 ° C were carried out. The final reduction in area was 92%. All other conditions remained unchanged.

In Fig. 10, the hysteresis loops are those so produced Line rods shown. In this figure, denote by the reference symbols Γ, 2 and 3 marked curves show the data of the conductor wires at temperatures 700.900 and 1100 ° C in the final Annealing treatment. In Table X the most important ones correspond to the hysteresis loops Dates given.

Table X
Hysteresis loop

As can be seen from Fig. 10, both the Re corner ratio as well as the course fill factor »rr greater, the lower the temperature of the final annealing treatment.

An X-ray streak was used for the alloys

fi5 diffraction performed and the following ermil The alloy subjected to the final annealing treatment at a temperature of 700 ° C a mixed phase of an α-phase with an ra

Temperature of B ₁₀₀ Br Hc final in kilogauss in kilogauss in C Annealing treatment in-C 16.2 16.0 29 700 15.0 14.5 31 900 14.5 12.5 3! 1 100

centered cubic lattice structure and a j--Pha.se with a face-centered cubic lattice structure. In contrast, the one showed a final Alloy exposed to annealing treatment at a temperature above 900 ° C, a single phase, namely a j-phase. It was also found that the alloy having the mixed phase with regard to the plastic processing wedge. the squareness ratio and the curve fill factor is superior and is therefore excellent as a semi-hard magnetic material.

Example 5

The procedure according to Example 5 was repeated, except that the curing treatment was carried out in the case of those in Table XI indicated different temperatures was carried out. The coercive force (Wc) of the treated Alloy is shown in Table XI and in FIG. 11 illustrates. In Fig. 11, the curves denoted by the reference numerals 1, 2 and 3 give the data of Alloys that were subjected to the final annealing treatment at 700, 900 or 1100 ° C.

• 10 .100 Table XI 400 500 G (X) 700 800 900 44 '5.5 46 36 29 22nd 9 3.5 temperature
from the 39 47 Coercive force (Wc) in Oe 51 41 31 24 9 2.5 closing 31 37 Hardening temperature in C 41 36 31 26th 12th Incandescent treatment in C 700 900 1100

As shown in Table XI and Fig. Il can be seen, reaches the coercive force (Wc) at a curing temperature of approximately 400 C and then fills with increasing curing temperature. Is the curing temperature higher than 800C, then the coercive force (Wc) is below about 10 Oe. The curing should therefore preferably be carried out at a temperature not above 800.degree.

For this purpose 2 sheets of drawings

Claims (3)

Patent claims: 1. Using an alloy consisting of (a) cobalt, (b) iron (c) nickel and Id ₁ ) niobium or Id ₂ ) niobium and at least one metal from the group tantalum, titanium, vanadium, zirconium, molybdenum, chromium and tungsten, with the proviso that that Weight ratio of (a) cobalt to (b) iron in the range of 3: 2 to 1: 2 and the iq Weight ratio of (c) nickel to (b) iron in the range from 1: 1 to 1: 3 and the proportion of (d,) or (di) 1 to 5 percent by weight of the total alloy, as well as the usual manufacturing-related ones Impurities that hardened at 600 to 900 ° C and then with intermediate annealing has been cold-worked by at least 75% at temperatures of at least 600 ° C, as a semi-hard magnetic material. 2. Use of an alloy of the composition according to claim 1 and treated according to claim 1, which has been re-annealed after cold working at a maximum of 800 ° C, for the Purpose according to claim 1. 3. Use of an alloy of the composition according to claim 1 and treated according to claim 1 or 2, in which the component (d ₂ ) consists of less than 30% of one or more of the metals tantalum, titanium, vanadium, zirconium, molybdenum, chromium and / ode .- Tungsten and the remainder niobium, for the purpose according to claim 1.