JPH1081944A - Co-base metal-glass alloy - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a Co-base metal-glass alloy capable of being produced in bulk and utilization as a magnetic material at ordinary temps. SOLUTION: This alloy consists of a Co-base alloy for which ΔTx= Tx-Tg>=40 K (where Tx is a crystallization initiating temp., Tg is a glass transition temp., and K is a absolute temp.). This alloy consists essentially of Co and further may contain metals such as Al, Ga, In and Sn and metalloids such as P, C, B, Si and Ge besides Co. For example, the alloy is composed of 1-10 atomic % Al, 0.5-4% Ga, 10-17% P, 0.5-7% C, 2-10% B and the balance Co with inevitable impurities.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Co-based metallic glass alloy, and more particularly to a Co-based metallic glass alloy which can be obtained as a bulk alloy having a thickness much larger than that of a conventional amorphous alloy ribbon and has excellent magnetic properties. A Co-based metallic glass alloy.

[0002]

2. Description of the Related Art Some conventional multi-element alloys are
Prior to crystallization, it has a wide temperature range that is in a supercooled liquid state, and these are known to constitute metallic glass alloys. This metallic glass alloy has a much thicker bulk shape (lines, wires, etc.) than conventionally known amorphous alloy ribbons.
Non-specified lumps such as grains, ribbons, ribbons, films, etc.)
It is also known to be an alloy of

For example, as such a metallic glass alloy,
Ln-Al-TM (Ln is a lanthanide metal, TM is a transition metal), Mg-Ln-TM, Zr-Al-TM,
Compositions such as Hf-Al-TM and Ti-Zr-Be-TM are known.

[0004]

Among alloys having various compositions other than those described above, some alloys exhibit a supercooled liquid state. However, the temperature interval ΔTx between these supercooled liquids, that is, the crystallization starting temperature (Tx) and the glass Considering that the difference (Tx-Tg) from the transition temperature (Tg) is remarkably small and therefore practically poor in metallic glass forming ability and lacks practicality, a wide supercooling like the metallic glass alloy described above is taken into consideration. The existence of an alloy that has a liquid temperature range and can form a metallic glass by cooling overcomes the limitation of the thickness of a conventionally known amorphous alloy as a ribbon, and has attracted much attention in metallurgy. Things.

However, none of the conventionally known metallic glass alloys has magnetism at room temperature (normal temperature), and in this respect, there are great restrictions and limits on practical and industrial use values.

Accordingly, an object of the present invention is to provide a Co-based metallic glass alloy which can overcome the morphological limitations of conventional metallic glass alloys, can be manufactured as a bulk material, and can be used as a magnetic material. It is in.

[0007]

SUMMARY OF THE INVENTION The present invention makes it possible to manufacture a bulk glass alloy, which has not been known, and provides a metallic glass alloy having excellent magnetic properties at room temperature. Is what you do.

The metallic glass alloy of the present invention developed to fulfill the above object has a temperature interval ΔTx of a supercooled liquid represented by the following formula: ΔTx = Tx−Tg (Tx is a crystallization start temperature, Tg Indicates the glass transition temperature) is 40K
It is characterized by comprising the above-mentioned Co-based alloy.

As an embodiment of the present invention, other metals and metalloid elements may be contained in addition to Co. Here, the other metal element may be at least one of metal elements belonging to Group IIIB and Group IVB of the periodic table, and the metalloid element may be P, C, or
At least one of B, Si and Ge may be used.

Conventionally, glass transitions have been observed in Co-based alloys.
Are extremely small at 25K or less, and cannot be practically constituted as a metallic glass alloy. On the other hand, the present invention, which has a very wide temperature range in which the temperature interval ΔTx of the supercooled liquid is 40 K or more, is completely unexpected from a conventional Co-based alloy. Moreover, the alloy of the present invention, which is also excellent in magnetic properties, is far more practical and industrially excellent than the conventional amorphous alloy, which was practical only as a ribbon.

The composition of the metallic glass alloy of the present invention can be described as containing Co as a main component as described above and further containing other metals and metalloid elements. Other metals are group IIA, IIIA and IIA of the periodic table.
It can be selected from the group IB, IVA and IVB, the group VA, the group VIA and the group VIIA. Among them, the metal elements of the group IIIB and the group IVB (for example, Al, Ga, I
n, Sn) are indicated as preferred.

Further, Ti, Zr, Hf, V, Nb, T
Metals such as a, Cr, Mo, W, Mn, Fe, Ni, and Cu can also be blended. Examples of the metalloid element include, for example, P, C, Si, Ge, and B. More specifically, the composition is such that Al is 1 in atomic percentage.
-10%, Ga is 0.5-4%, P is 10-17%, C
Is 0.5 to 7%, B is 2 to 10%, and the balance is Co, and may contain unavoidable impurities. Also,
Alloy composition containing 7% or less of V, Nb, Ta, Cr, Mo and W, Ni of 10% or less and / or 30%
A composition containing the following (all in atomic percentage) Fe is also exemplified.

In any of the above compositions, the Co-based metallic glass alloy of the present invention has a temperature difference Δ of the supercooled liquid.
Tx is 40K or more. In order to produce the above-mentioned metallic glass alloy of the present invention, it is possible to produce by melting and casting, a liquid quenching method such as a single roll method or a twin roll method, a liquid spinning method, a solution extraction method, a high pressure gas injection method, and the like. Thus, it can be manufactured in a shape such as a bulk material, a ribbon material, a linear material, and a powder. In such a manufacturing method, it is possible to obtain a bulky metallic glass alloy having, for example, a thickness and a diameter five times or more as compared with the case of a conventionally known amorphous alloy.

In addition to the above-mentioned production method, a suitable cooling rate is determined by the composition of the alloy, the type of the production method, the size and the shape of the product, etc., but usually 1 to 10 ² K
/ Second range can be used as a guide. And actually, Co ₂ P and Co ₄ as crystal phases are added to the glass phase.
The cooling rate and the like can be determined by confirming whether a phase such as B, Co ₃ B or the like precipitates.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION

Example 1 Co, Cr, Al and Ga metals and F
Using e-C alloy, Fe-P alloy, and Fe-B alloy as raw materials, these raw materials are induction-melted in an Ar atmosphere, and the atomic composition ratio is Co ₇₀ Cr ₃ Al ₅ Ga ₂ P ₁₅ C ₁ B.
An alloy block of No. ₄ was produced. Using this alloy, the cross-sectional area is 0.02 × 1.5 mm in an Ar atmosphere by a single roll method.
Was produced.

The ribbon is subjected to X-ray diffraction and TEM (Transmis
As a result, it was confirmed that the film was in a metallic glass state. Also DSC (Differen
The glass transition and crystallization were evaluated by a tialScanning Calorimeter. As a result, the glass transition temperature (T
g) and the temperature interval (ΔTx) of the supercooled liquid represented by the difference (Tx−Tg) between the crystallization onset temperature (Tx) and 51 K.

The magnetic properties (Bs; saturation magnetic flux density, Hc; coercive force, μe; effective permeability) of the above alloy at room temperature were evaluated by experiments.
Hc = 4.5 A / m, μe = 5800 (f = 1 kHz)
And excellent values. [Example 2] In the same manner as in Example 1, the atomic composition ratio was Co.
The ₇₀ Cr ₃ alloy of _{Al 5 Ga 2 P 15 C 1} B 4 was melted.
Using this alloy, injection molding was performed using a Cu mold to prepare a rod-shaped alloy sample having a circular cross section. Sample length is about 50mm, diameter 0.5mm, molding pressure is 0.05MP
a.

Observation of the appearance of the sample showed that it had a smooth surface, good metallic luster, and good moldability. Then 0.5% hydrofluoric acid and 99.5
% Was etched at 293K for 10 seconds, and the cross section was observed with an optical microscope.
The existence of a crystal phase was not confirmed at all, and it was found that it consisted of only a glass phase. In addition, a broad peak was observed in the result of X-ray diffraction, and it was confirmed that the glass phase was a single phase. The magnetic properties were equivalent to those of Example 1.

[0019]

As described above in detail, according to the present invention, the limitations such as the thickness of the conventional amorphous alloy ribbon can be overcome.
It is possible to provide a Co-based metallic glass alloy which can be manufactured as a bulk material and can be applied as a magnetic material having excellent magnetic properties.

Claims (8)

[Claims] 1. A Co-based alloy wherein ΔTx = Tx-Tg (Tx indicates a crystallization start temperature and Tg indicates a glass transition temperature) is 40 K (K; absolute temperature) or more.
-Based metallic glass alloy. 2. The Co-based metallic glass alloy according to claim 1, wherein the composition contains a metal other than Co and a metalloid element. 3. The Co according to claim 2, wherein the metalloid element is at least one of P, C, B, Si and Ge.
-Based metallic glass alloy. 4. The Co-based metallic glass alloy according to claim 2, wherein the other metal element is at least one of Group IIIB and IVB metal elements in the periodic table. 5. The method according to claim 1, wherein the other metal elements are Al and G.
The Co-based metallic glass alloy according to any one of claims 2 to 4, wherein at least one of a, In, and Sn is contained. 6. The composition (atomic percentage) of Al = 1 to 10
%, Ga = 0.5-4%, P = 10-17%, C = 0.
6. An apparatus according to claim 1, wherein 5 to 7%, B = 2 to 10%, and the balance is Co and 0% or more inevitable impurities.
The Co-based metallic glass alloy according to the item. 7. The composition according to claim 1, wherein the composition contains at least one of V, Nb, Ta, Cr, Mo and W in an atomic percentage of 7% or less. Co-based metallic glass alloy. 8. The Co-based metallic glass alloy according to claim 1, which contains 10% or less of Ni and / or 30% or less of Fe in atomic percentage.