JPS61558A - Amorphous alloy having increased ac magnetic characteristicsat high temperature - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to amorphous alloy compositions, particularly amorphous alloys containing iron, silicon and boron with high temperature enhanced AC magnetism.

Research has shown that solid crystalline negative materials are undervalued due to the strength of alloy compositions. Amorphous materials have virtually no extensive atomic order and are characterized by an X-ray diffraction pattern with a wide range of intensity maxima. Such a pattern is similar in nature to the diffraction pattern of a liquid or an ordinary window glass. This is in contrast to crystalline materials, which produce diffraction patterns with sharp and narrow intensity maxima.

These amorphous materials are in a metastable state. When heated to a sufficiently high temperature, they release heat of crystallization and crystallize, and the X#i1 diffraction pattern changes from having amorphous characteristics to having crystalline characteristics.

A new amorphous alloy, S. Cheno and E.

Yoneyama Patent No. 385fi513 (1) by Bork
Published December 24, 1974).

These amorphous alloys have the formula MaYbZo, where M is at least one metal selected from the group of iron, nickel, cobalt, chromium, and vanadium, and Y is phosphorus, boron, and tandem metal. At least one element selected from the group is aluminum, antimony,
At least one element system selected from the group consisting of beryllium, germanium, indium, tin, and silicon;
˜30 atom %, and “c” is about 0.1 to 15 atom %. These amorphous alloys have been found suitable for a wide range of applications in the form of ribbons, sheets, wires, powders, etc. The Cheno and Bork patent also discloses an amorphous alloy with the formula TiXj, where T is at least 1
Species M transfer metal, where X is aluminum, antimony,
At least one element selected from the group consisting of beryllium, boron, germanium, carbon, indium, phosphorus, silicon, and tin, and Jl is about 70 to 87 atomic%, and Jl is about 13 to 30 atomic%. . It was found that these amorphous 'J gold alloy wires are suitable.

U.S. Pat. No. 4,30Q950 essentially describes 12-15% boron, 1-8% silicon and 80-84% iron.
An amorphous alloy consisting of (atomic %) is shown. These alloys exhibit relatively low crystallization temperatures and Curie fluxes (ie, below 400°C). As such, their magnetic properties are substantially reduced by prolonged heat aging, and the induction levels of these alloys are relatively low at high temperatures. These alloys are therefore suitable for power magnetics applications where operating temperatures often exceed 100°C.
tion).

European Patent Application No. 015831 (filed on March 28, 1983) contains 4-10% boron and 14-17% silicon.
% and 73-80% (atomic %) iron, and an amorphous alloy with accompanying impurities. These alloys exhibit high excitation power (for example, about 3 to 5 VA/kli+ at 60 Hz and 1.4 T) and are not sufficiently suitable for power supply magnetic materials that require low excitation power.

European Patent Application No. 09 to 803 (filed on March 28, 1983) contains 6-10% boron and 14-17% silicon.
% and 1 to 4% chromium (JJA%), enriched no more than incidental impurities, and with the remainder being iron, an amorphous alloy is shown. These chromium-based alloys have relatively low intrinsic saturation inductions and relatively low Curie temperatures, making them unsuitable for high temperature, high conductivity applications.

U.S. Pat. No. 4,437,907 describes silicon 8 to
An amorphous alloy with attendant impurities of 19%, 6-13% boron, 0-3.5% carbon, and 74-80% iron (atomic %) is shown. These alloys exhibit low crystallization temperatures (eg, below 515° C.) and are therefore not well suited for power supply magnetics.

European Patent Application No. QO5a269 (May 1981)
May 8th) contains essentially 12-16% boron and 5-5% silicon.
Amorphous alloys containing no more than 10% iron and 77-80% (atomic %) iron and no more than blinding impurities are shown.

There is no mention of alloys that exhibit enhanced induction at elevated temperatures and long-term thermal stability.

When the amorphous alloys mentioned above were discovered, they exhibited superior magnetic properties to the polycrystalline alloys known at the time.

Nevertheless, for new applications requiring improved magnetic overcoat and high thermal stability at elevated temperatures,
Efforts were required to develop other alloy compositions.

According to the invention, the material is at least 90% amorphous and essentially of the formula Fe aS i bB o (where Ial, @b
w and "C" are atomic %, each from about 79.4 to
79.8 or more, 6 to 8 or more, and 12 to 14, provided that the sum of IaI, @bl and lC1 is 1
00) is provided.

The alloys of the present invention have at least 90
% is amorphous, preferably at least 97% amorphous, most preferably 100% amorphous. These alloys can be prepared using a known method consisting of preparing a melt of the desired composition and quenching the molten alloy by casting it on a rapidly rotating cooling wheel at a rate of at least about 0.5°C/sec. processed by the method.

Further, the present invention provides at least 90% amorphous and essentially a formula FeaS1bB, (where 1 a l , a
bl and "c" are atomic percent, each about 79.
4 to 79.8 or more, 6 to 8 and 12 to 14, provided that the sum of 1a1, l bl and ICI is 100
Provided is a method for increasing the magnetism of an alloy comprising a composition having the following properties, the method comprising the step of annealing an amorphous alloy.

Further, in the present invention, at least 90% is amorphous y1,
Essentially 2F'5abibB0 (in the formula "a I,
I bl and fCl are atomic %, each about 79
．． 4-79.8.6-8 and 12-14, where the sum of 1a'', @b'' and l c I is 100
A core Kl for an electromagnetic device is provided, which is made of an alloy having a composition having the following properties.

The alloys of the present invention exhibit improved AC magnetism at temperatures of about 100-150°C. These alloys are therefore used in power transformers, aircraft transformers, current transformers, high frequency transformers (such as transformers with operating frequencies ranging from approximately 400 Hz to 100 KHz), switch cores, high gain magnetic amplifiers,
Particularly suitable for use in low frequency inverters and low frequency inverters.

The present invention will be better understood, and other advantages will become apparent, from the following detailed description and accompanying drawings.

Figure 1 shows the thermal stability (i.e. 1.4T/60 as a function of iron content) for alloys within and outside the scope of the present invention.
Figure 2 is a graph comparing the change in excitation power (%) in Hz as a function of iron content for alloys within and outside the scope of the present invention (i.e., 8000 A/m
and induction measured at 100°C).

The composition of the novel amorphous % Fθ-8i-B alloy according to the present invention is approximately 79.4 to 79.8 atomic % iron, 6 to 8 atomic % silicon.
% by atom, and 12 to 14 atomic% by boron. Compositions of this type exhibit enhanced AC magnetism at low temperatures. Their improved magnetism is evidenced by high magnetization, low core loss and low voltage and current requirements, which range from about 100 to
Constant and stable at temperatures in the range of 150°C. Within the above range, a preferred composition consists of 79.5 atomic percent iron, 13 atomic percent boron, and the balance is silicon.

The alloys of the present invention are at least about 90% amorphous;
Preferably it is at least about 97% amorphous, and most preferably 100% amorphous.

Alloys with larger volume % amorphous constraints have improved demagnetism. Conveniently, the volume percentage of amorphous material is determined by X-ray diffraction.

These amorphous alloys have a melt purity of approximately 105 to 100% of the purity of all materials commonly found in commerce. Various techniques are used to process metal foils by splat quenching and continuous ribbons, wires, sheets, etc. by rapid quenching. Generally, a specific composition is chosen, powders or granules of the required elements (or materials that decompose to produce these elements, e.g. ferroboron, ferrosilicon, etc.) are melted and homogenized in the desired proportions, and this molten alloy quench quickly on a cooling surface, for example a rotating cylinder.

A most preferred method for processing continuous metal strips containing the alloys of the present invention is disclosed in U.S. Pat. No. 4,142,571 (Nara-θimhan).
This is shown in The Narasimhan patent (which is incorporated herein by reference) shows a method for forming a continuous metal strip by depositing molten alloy on the surface of a moving cooling body. This method involves moving the bottom surface of a fat cooling body longitudinally at a constant predetermined speed of about 100 to about 2000 m1, with a lip-to-surface gap of about 0.03 to about 1 m in proximity to the surface. the orifice of a slotted N nozzle defined by a pair of generally parallel lips located at a
The method consists of contacting a stream of molten metal with the surface of a cooling body moving through an orifice of a nozzle and solidifying the metal therein to form a continuous strip. Preferably, the nozzle slot has a width of about 0.34 to 1 wing, and the first lip has a width at least equal to the width of the slot;
The second lip has a width approximately 1.5 to 3 times the slot width,
The amorphous metal strip produced by the Narasimhan process is at least about 7 im, preferably at least about 3 cIr.
Has LO width. The strip is at least 0.02 mm thick, but may be about 0.14 ii or more thick depending on the melting point, solidification and crystallinity of the alloy used.

The alloy of the present invention has a melting point and a high under-cooling temperature.
cooling), so it has improved processability compared to other iron-based metallic glasses.

The magnetism of the alloy of the present invention can be increased by annealing the alloy. The method of annealing is generally sufficient to relieve stress;
However, it consists of heating the alloy to a temperature lower than that required to initiate crystallization, cooling the alloy, and applying an alloy VC field during heating and cooling. Generally about 340 ~
A temperature of 440° C. is used during heating. Approximately 0.5~
A cooling rate range of b is used, with rates of about 1 to b being preferred.

As noted above, the alloys of the present invention exhibit improved magnetism (particularly higher saturation induction), which is stable at temperatures from about 100 to about 150°C, rather than the maximum 125°C exhibited by prior art alloys. .

The increased temperature stability of the alloys of the present invention allows them to be used in high temperature applications, for example as transformer cores for distributing Fi power to residential or commercial consumers.

More specifically, for the above Fe-B-8i composition, by appropriately selecting the annealing conditions, loss characteristics and excitation power characteristics of 4Mi can be achieved. However, two other criteria, namely saturation induction at high temperatures and thermal stability, are extremely important for applications as power supply magnets and must be optimal.

Saturation induction at high temperature is B8000A/at 100℃
It can be roughly estimated by measuring m. FIG. 2 shows saturation induction (i.e., B 4 measured at 8000 A/m and 100° C.) as a function of iron content for FB-E-Si containing alloys within and outside the scope of the present invention.
It is illustrated by a graph consisting of . As shown in FIG. 2, the saturation induction at 100° C. for alloys containing about 79.4% JJA% iron or higher is about 1% higher than for those with iron contents lower than 79.4%. From a loss evaluation point of view, this gain in operational induction at elevated temperatures reduces the dimensions of the transformer and significantly increases the inherent value of amorphous alloys as power source magnetic fur materials.

A wide range of thermal stability was described by Duck et al. in the proceedings of the Symposium on Chemistry and Physics of Rapidly Solidified Materials (held by the Institute of Engineering, Engineering and Metals, October 26-27, 1982 in St. Louis, Missouri). It can be approximated by the accelerated aging process discussed above.The accelerated aging process is
Significant soft magnetic changes in the prototype core exposed to temperatures higher than normal operating temperatures (i.e. 1.4T/60Hz
Estimate the change in VA (%) in this characteristic. It consists of extrapolating to the operating temperature. Figure 1 shows the accelerated aging (i.e., thermal stability) behavior (i.e., variation in excitation power at 1.4 T/60 Hz as a function of iron content) for 'e-B-8i containing alloys within and outside the scope of the present invention. %).

Aging treatment was performed at 240°C for 2200 hours. As shown in FIG. 1, alloys containing more than about 79.8 atomic percent iron had substantially increased excitation power (ie, were significantly aged). Advantageously, for alloys within the scope of the present invention having iron contents of about 79.4-79.8 or higher, saturation induction and thermal stability at elevated temperatures have been simultaneously optimized.

When cores made of the alloys of the invention are used in electromagnetic devices, such as transformers, they exhibit very high magnetization, low core losses and low voltage and current requirements, thus resulting in more efficient operation of the electromagnetic device. Energy is dissipated in the form of heat due to the energy loss that occurs in the magnetic core as a result of eddy currents circulating through the core. Cores made from the alloys of the present invention require less electrical energy to operate and generate less heat. Applications that require cooling equipment to cool the transformer core, such as aircraft transformers and large power transformers, require less heat to be generated by cores made from the alloys of the present invention. Further savings are realized because there is less cooling equipment required. Additionally, the significantly higher magnetization and higher efficiency of cores made from the alloys of the present invention result in cores with low basis weight for a given capacity rating.

The following examples are presented to better understand the invention.

The specific techniques, conditions, materials, proportions and data reported to illustrate the principles and practice of the invention are illustrative and should not be construed as limiting the scope of the invention.

Examples Alloy ribbons of various compositions containing iron, silicon and boron (width 0.0254 m) each containing approximately 0.030 mm and 0.00 mm.
Circular samples were prepared by winding them onto steatite cores having inner and outer diameters of 0.0397 m and 0.0445 m. A Q of 795.8 A/m was applied to the annealing head by winding a high-temperature manonet 1150 times around the ring.
C, Circumferential magnetic field was applied. The samples were annealed in an inert gas atmosphere at a temperature of 340-440° C. for 2 hours, a magnetic field of 795.8 A/m was applied during heating and cooling, and the optimum magnetic field annealing performance was determined for each composition. The optimum magnetic field annealing conditions for each composition are those that result in the lowest core excitation power. The sample was cooled at a rate of approximately 0°C/min.

AC magnetism of the sample, i.e. t force loss (W/9) Oh! Pi excitation mW, power (RMS 'MA/to!V) 11 waves 60
It was measured by the sine field flux method at Hz and magnetic strength of 1.4 tes2.

& pot annealed A for various alloy compositions within the scope of the present invention
Table 1 shows the Ci values.

Table 1 Fe B Si Power Loss Original Power Power Loss Version Example (i%) (W#) (VAAli) for amorphous alloys within the scope of the present invention
') (W#) (VAAg)1 79.4 13.5
7.1 0.217 0.4170.198 0.4
292 79.5 13 7.5 0.220 0.
3310.221 0.3123 79.6 13
7.4 0.218 0.321 0.203 0.3
174 79.8 12.5 7.7 0.236 0
．． 3270.255 0.3615 79.8 14
6.2 0.218 0.3830.239 0.4
376 79.8 13.5 6.7 0.248 0
．． 4180.271 0.467 For comparison, the compositions of some amorphous alloys outside the scope of the present invention and their magnetic field annealed AClil constant values are shown in Table 2. These alloys have higher core losses and higher voltage flow requirements X at room temperature and 100° C. in contrast to those within the scope of the present invention.

Table ■ Open side (atomic %) for amorphous alloys not included in the scope of the present invention
) (W#) (MA/に9) (W#) (V
A#) 7 7.8 13 9 0.2631.03 0
．． 2571.118 78.41110.60.381
2.91 0.4273.339 78.812.58
．． 70.2010.798 0.2170.81310
79 13 8 0.2100.637 0.201
0.6411179°213 7.80.2200.6
01 0.2130.58312 80 11 9 0
．． 3901.77 0.3392.30 To illustrate the improved saturation induction of the synthetic compositions of the present invention at elevated temperatures, samples 1-6 from Table 1 were further tested at 8000 A/m
Trial sales were carried out by excitation at 100° C. with a driving magnetic field of The improved saturation induction of the alloys thus tested is shown in Table m.

Table ■ Composition F'e, B Si saturation induction (T)
=179.413.57.1 1.50279.51
37.5 1.51 379.6137.4 1.51 479.812.57.7 1.51579.814
6.2 1.51 679.813.56.7 1.51 For comparison, some compositions of amorphous alloys outside the scope of the present invention as well as 800
Their saturation induction measurements at a driving magnetic field of 0 A/m and at 100° C. are shown in Table 3.

■ Solubility induction composition of amorphous alloy outside the scope of the present invention Fe B Si Saturation induction (T) near 78 13 9 1.47 878.411 10.6 1.48978.812
．． 58.7 1.501079 13 8 1.5
0 1179.213 7.8 1.501280 11
9 1.49 Although the present invention has been described in considerable detail above, it is not necessary to strictly follow these details, and it is obvious that those skilled in the art may make further changes and modifications, all of which are covered by the patent claims. does not fall within the scope of the present invention as defined by the scope of the invention.

[Brief explanation of drawings]

Figure 1 shows the thermal stability (i.e. 1.4T/60 as a function of iron content) for alloys within and outside the scope of the present invention.
Figure 2 is a graph comparing the variation of excitation power in Hz (%'I) as a function of iron content for alloys within and outside the scope of the present invention (i.e., 8000 A/m
and induction measured at 100°C). Patent applicant: Allied Corporation (5 others) 4'ah@machiBF1000 A'nq)ioo'

Claims (10)

[Claims] (1) At least 90% amorphous and essentially of formula F
e_aSi_bB_c (in the formula “a”, “b” and “c
” are atomic % and are approximately 79.4 to 79.8 and 6, respectively.
~8, and 12~14, where "a", "b"
and "c" is 100), wherein the alloy has a power loss of 0.3 W/kg or less and an excitation power of 1 VA/kg or less, Alloy whose excitation power was measured at 100° C. at 60 Hz and 1.4 T. (2) The amorphous alloy of claim 1, wherein the alloy is at least about 97% amorphous. (3) The amorphous alloy according to claim 1, wherein the alloy is 100% amorphous. (4) "a" and "c" are respectively 79.3 to 79.
7 and 13, the balance being silicon. (5) The alloy according to claim 1, wherein the alloy has an induction of at least 1.50 T at 100° C. and a driving magnetic field of 8000 A/m. (6) At least 90% amorphous and essentially of formula)
Fe_aSi_bB_c (in the formula “a”, “b” and “
c” is atomic % and is approximately 79.4 to 79.8, respectively;
6 to 8, and 12 to 14, with “a” and “b”
and "c" is 100), the method comprising the step of annealing the alloy. (7) heating the alloy to a temperature sufficient for annealing to relieve stress, but lower than required to initiate crystallization; and applying a magnetic field to the alloy during said heating and cooling. (8) The method according to claim 7, wherein the temperature range for heating the alloy is about 340-440°C. (9) The annealing step heats the alloy to a temperature in the range of about 340-440°C; cools the alloy at a rate of about 1°C/min to 16°C/min; and applies a magnetic field to the alloy during said heating and cooling. 7. A method according to claim 6, comprising providing. (10) at least 90% amorphous and essentially of the formula Fe_aSi_bB_c, where "a", "b" and "c" are each about 79.4 to 79.
8, 6-8, and 12-14, with the exception of "a",
(the sum of "b" and "c" is 100); at a predetermined speed past the location of an orifice of a nozzle slot defined by a pair of generally parallel lips positioned proximate said surface such that the gap between said lips and said surface is from about 0.03 mm to about 1 mm. At least move it,
The orifice is generally arranged perpendicular to the direction of movement of the cooling body and (b) directs the molten metal stream through the orifice of the nozzle and into contact with the surface of the moving cooling body, solidifying the metal therein and causing continuous Form a strip and (
c) Annealing the alloy to improve its power loss and excitation power such that the power loss is 0.3 W/kg or less and the excitation power is 1 VA/kg or less (these power losses and excitation power are 60 Hz and 1.4 T) (measured at 100°C).