JPH07188877A - Amorphous alloy for biological use - Google Patents

Abstract

PURPOSE:To provide amorphous alloy for biological use excellent in the corrosion resistance and the strength, and excellent in the amorphous formability by constituting the alloy from Zr, Ti, Hf, Pd, Pt, Al, Cu, Co and Ni at the prescribed ratio. CONSTITUTION:The amorphous alloy for biological use has the composition as indicated by the formula, Zr100-a-b-cMaAlbXcYd (wherein, M is one or more kinds of Ti and Hf or its mixture, X is one or more kinds of Pt and Pd or its mixture, Y is one or more kinds of Cu, Co and Ni or its mixture, a, b, c, d are the atm.% respectively to satisfy the inequalities of 5<=a<=55, 2<=b<=30, 2<=c<=45, 5<=d<=40, 20<=a+b+c+d<=80). The amorphous formability is deteriorated when either of the total content of Ti and Hf, that of Pt and Pd, or that of Ti, Hf, Al, Pd, Pt, Cu, Co and Ni is other the range. When the content of Al is below the lower limit, the corrosion resistance and the strength are low, and when the content of Al is above the upper limit, the amorphous formability is deteriorated. The amorphous formability is deteriorated when the total content of Cu, Co and Ni is below the lower limit, while the corrosion resistance is deteriorated when the total content is above the upper limit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an amorphous alloy for living body. More specifically, the present invention relates to an amorphous alloy for living body, which is useful for implant materials, medical equipment, etc. in the fields of dentistry and orthopedics, has excellent corrosion resistance, high strength, and excellent amorphous forming ability.

[0002]

2. Description of the Related Art It has been known that amorphous alloys having various compositions and shapes can be obtained by rapidly cooling molten alloys. This amorphous alloy is often manufactured by a single roll method that easily realizes a high cooling rate. So far, Fe system, Ni system, Co system,
Many amorphous alloy materials have been developed for Al-based, Zr-based, and Ti-based alloys. Among them, Zr and Ti
Amorphous amorphous alloys have significantly better corrosion resistance than Al-based amorphous alloys, and have high applicability to human bodies and safety,
Moreover, since it exhibits high thermal stability and the width of the supercooled liquid region is wide, it is possible to perform processing using the supercooled liquid region. It is expected to be applied to various fields as a different type of amorphous alloy material.

On the other hand, metallic materials currently used for living bodies include precious metals, Co-based alloys, stainless steel and T.
The i alloy is the majority. Conventionally, among such bio-alloys, for example, as a metal material for implants, Co-based alloys such as Co-Cr-Mo-based cast alloys (vitallium), stainless steel, and more recently Ti- A Ti alloy represented by 6Al-4V is used. Precious metals have been widely used as dental metal materials since ancient times, and stainless steel is widely used as scalpels, scissors, tweezers, clips and the like as metal materials used in medical equipment and the like.

[0004]

As described above, the Co-based alloy, the stainless steel and the Ti alloy are used as the biomedical metal material. In the case of the Co-based alloy or the stainless steel, Fe, Co, There is a problem that a large amount of toxic elements such as Cr are contained in the living body, and when these materials are used in the living body for a long time, these elements flow out into the living body. In addition, since Ti alloys generally have low strength and further contain elements having strong cytotoxicity such as V, it has been difficult to use such Ti alloys as biomaterials.

Therefore, unlike conventional crystalline alloys, the development of an amorphous alloy having excellent corrosion resistance and high strength has been strongly desired. Further, for example, since it is necessary to process into bulk materials having various shapes as a biomaterial, it is desired to manufacture a powdery amorphous alloy which can be easily applied with a solidification technique. Therefore, in the case of an alloy system containing an active metal element such as Al, Ti or Zr, it is produced by a high pressure gas atomizing method using an inert gas. In this method, a general method for producing an amorphous alloy for living organisms is used. The cooling rate is smaller than that of the single roll method, etc., and even if atomization is performed using an alloy composition that can produce an amorphous alloy with a thickness of about 30 μm by the single roll method, an alloy powder consisting of an amorphous single phase is obtained. There was a problem that it was not easy to obtain.

Therefore, there has been a strong demand for realization of an amorphous alloy for living body which has an excellent ability to form an amorphous body and can easily obtain an amorphous alloy even in the case of the gas atomizing method having a slow cooling rate.
The present invention has been made in view of the above circumstances, solves the drawbacks of the prior art, is excellent in corrosion resistance, high strength, and is excellent in amorphous forming ability even if the cooling rate is slow It is intended to provide an amorphous alloy.

[0007]

The present invention is to solve the above-mentioned problems, and the gist of the present invention is to provide a composition formula:
Zr _100-abcd MaAlbXcYd (where M is Ti
And one element selected from the group consisting of Hf or a mixture thereof, X is one element selected from Pt and Pd or a mixture thereof, and Z is one selected from a group consisting of Cu, Co and Ni. Elements or mixtures thereof,
a, b, c and d are each represented by atomic%, and 5 ≦
a ≦ 55, 2 ≦ b ≦ 30, 2 ≦ c ≦ 45, 5 ≦ d ≦ 4
0, 20 ≦ a + b + c + d ≦ 80), which is an amorphous alloy for living body.

In the amorphous alloy of the present invention, it is essential that the alloy is based on Zr and is a combination of the above-mentioned elemental components. Of these, Ti and Hf are both essential elements for obtaining an amorphous alloy excellent in strength, corrosion resistance and amorphous forming ability, and one of them selected from the group consisting of Ti and Hf. The content of the element or the mixture thereof needs to be 5 atomic% or more and 55 atomic% or less, and preferably 10 atomic% or more and 45 atomic% or less. When the content of these elements is less than 5 atom% or more than 55 atom%, the amorphous forming ability is lowered, and in the case of a liquid quenching method such as a high pressure gas atomizing method or a casting method, which has a relatively slow cooling rate. Amorphous single phase alloy cannot be obtained.

Next, the Al content must be 2 at% or more and 30 at% or less, preferably 5 at%.
It is desirable that the content is 25 atomic% or less. If the Al content is less than 2 atomic%, the corrosion resistance and strength are low and it cannot be put to practical use. On the other hand, if the Al content exceeds 30 atomic%, the amorphous forming ability is lowered, and an amorphous single phase alloy cannot be obtained in the case of the liquid quenching method in which the cooling rate is relatively slow.

Pd or Pt is an essential element for obtaining an amorphous alloy having an excellent amorphous forming ability, and the content of one or a mixture of Pd and Pd is 2 atomic%. It is necessary to be 45 atomic% or less, and the more preferable range is 3 atomic% or more and 35 atomic% or less. Pd or Pt content less than 2 atomic% or 4
If it exceeds 5 atomic%, the ability to form an amorphous material decreases, and an amorphous single phase alloy cannot be obtained in the case of the liquid quenching method in which the cooling rate is relatively slow. Furthermore, if the content of Pd or Pt exceeds 45 atomic%, the corrosion resistance decreases and it cannot be put to practical use.

In the biomedical amorphous alloy of the present invention, Cu, Co and Ni are essential elements for obtaining excellent amorphous forming ability and strength.
The element or mixture selected from the group consisting of i must be 5 atomic% or more and 40 atomic% or less, preferably 10 atomic% or less.
It is desirable that the content is at least 30 atomic% and not less than 30 atomic%. When Cu, Co and Ni are less than 5 atomic%, the amorphous forming ability of the alloy is lowered, and in the case of a liquid quenching method such as a high pressure gas atomizing method or a casting method, which has a relatively slow cooling rate, it is amorphous. A single phase alloy cannot be obtained. The content of these is 40 atomic%
If it exceeds, the corrosion resistance is deteriorated and it cannot be put to practical use.

In the present invention, Ti, Hf, A
The total content of 1, Pd, Pt, Co, Cu and Ni needs to be 20 at% or more and 80 at% or less, preferably 25 at% or more and 70 at% or less. When the total content of these elements is less than 20 atom% or more than 80 atom%, the amorphous forming ability is lowered, and the liquid quenching method such as the high pressure gas atomizing method or the casting method having a relatively slow cooling rate is used. In that case, an amorphous single phase alloy cannot be obtained.

In the case of stainless steel, Co alloy and Ti alloy used as conventional bioimplant materials, the tensile strength thereof is 1000 MPa or less, whereas the biocrystalline amorphous alloy of the present invention is Its tensile strength is 1500 MPa or more, and it has excellent strength. Further, the biomedical amorphous metal of the present invention has excellent corrosion resistance as well as excellent strength, and has significantly better corrosion resistance than austenitic stainless steel widely used as a biomaterial. Show. Therefore, even if the biogenic amorphous alloy of the present invention contains elements having strong biotoxicity such as Cu, Co and Ni, there is no problem in use.

Further, since the amorphous alloy for living body of the present invention has an excellent amorphous forming ability, it can be used in the liquid quenching method such as the high pressure gas atomizing method or the casting method, which has a relatively slow cooling rate. Also, an amorphous single phase alloy can be easily obtained.
Therefore, for example, by using the amorphous alloy powder of the present invention obtained by the high pressure gas atomization method, it is possible to provide a bulk material having an arbitrary shape by hot pressing or hot extrusion processing.

The biological amorphous alloy of the present invention is
Since it has excellent strength and corrosion resistance as well as high amorphous forming ability, it is possible to obtain an amorphous alloy by adding various elements in addition to the constituent elements. Add elements that are less toxic to living organisms (for example, Si, Au) within the range of a few atomic% or less,
A living body amorphous alloy can be obtained.

The amorphous alloy for a living body of the present invention can be obtained by cooling and solidifying by various methods from a molten state, but it is a single roll method, a twin roll method, a rotating liquid spinning method, a rotating liquid. It is desirable to use a liquid quenching method having excellent productivity such as a spraying method or a gas atomizing method. For example, since the amorphous alloy of the present invention has excellent amorphous forming ability, it can be easily amorphous by cooling and solidifying by an atomizing method using various liquid or gas refrigerants from a molten state. A spherical powder consisting of a single phase can be obtained. A high-pressure gas atomization method using a clean inert gas such as Ar or He is particularly suitable for producing such a spherical powder.

When these atomizing methods are applied to the alloy of the present invention, in the high pressure gas atomizing method,
The alloy of the present invention is melted in a ceramic crucible equipped with a stopper and a ceramic nozzle having a hole diameter of 0.5 mm to 5.0 mm in an argon atmosphere, and then the ejection pressure is 0.2 to 5.0 kg / cm in an argon atmosphere. ^A spherical amorphous alloy powder can be obtained by extruding the molten metal from the nozzle at ² and atomizing it with an inert gas such as Ar ejected at a pressure of 30 to ²⁰⁰ kg / cm ² .

[0018]

The present invention will be described in more detail with reference to the following examples. Examples 1 to 20, Comparative Examples 1 to 18 Examples 1 to 20 shown in Table 1 and Comparative Examples 1 to 1 shown in Table 2
After melting the alloys having the compositions of 16 in a quartz tube in an argon atmosphere and using a quartz nozzle having a hole diameter of 0.3 mm, on a copper roll having a diameter of about 20 cm rotating at 3000 rpm in an argon atmosphere. Jet pressure 0.3kg / c
It squirts out at m ² and is rapidly cooled and solidified, width 3mm, thickness 50μ
A continuous quenching ribbon of m was produced.

Next, the amorphous phase of these produced ribbons was identified, and the corrosion resistance and strength were measured. The results are shown in Table 1 and Table 2, respectively. X for phase identification
The state in which a halo pattern peculiar to the amorphous phase was obtained by the line diffraction method was determined to be amorphous, and the state in which the amorphous phase and the crystalline phase were mixed was determined to be crystalline. Corrosion resistance is 1N-H for quenched ribbon
It was immersed in Cl for 100 hours, and the corrosion amount was calculated. The strength σf is 30 m in length using an Instron tensile tester.
It was determined by performing a tensile test on a quenched ribbon of m at a strain rate of 4.2 × 10 ⁻⁴ .

Tables 1 and 2 show the structure, strength σf, and corrosion resistance (corrosion rate) of the thin ribbons manufactured and characterized as described above. As is clear from Table 1 and Table 2, in Examples 1 to 20 of the present invention, ribbons composed of an amorphous single phase were obtained. On the other hand, Comparative Examples 1, 2,
4, 6, 9 to 12, 14 and 15 are Ti,
Since Al, Pd, Zr, Hf or Pt was out of the composition range of the alloy of the present invention, the amorphous forming ability of the alloy was low and a ribbon of crystalline alloy was obtained.

As is clear from the results shown in Tables 1 and 2, the amorphous alloys of Examples 1 to 20 of the present invention all have a tensile strength of 1500 MPa or more, and Comparative Examples 1 to
16 amorphous or crystalline alloys outside the scope of this invention or commercially available thicknesses of Comparative Examples 17 and 18 50μ
The strength was remarkably superior to that of the thin stainless steel plate of m or the Ti plate.

Further, from the results of the corrosion resistance shown in Tables 1 and 2, the amorphous alloys of Examples 1 to 20 of the present invention were compared with Comparative Example 1
.About.7, 9, 11, 14 and 16, which are far superior to the amorphous alloys and crystalline alloys outside the scope of the present invention, and stainless steel of Comparative Example 17, the corrosion resistance was remarkably excellent.

[0023]

[Table 1]

[0024]

[Table 2]

Examples 21 to 40, Comparative Examples 19 to 24 Alloys having various compositions shown in Tables 3 and 4 were used, in an argon atmosphere, with a BN stopper and a hole diameter of 2.0 mm.
After melting 300g in a BN crucible equipped with a BN nozzle at the bottom, raise the stopper at 1400 ° C, and at the same time, extrude the molten metal from the nozzle at a jet pressure of 0.5 kg / cm ² in an argon atmosphere to form an angle of 45 1 from 18 high pressure gas atomizing nozzles with a diameter of 1 mm
Atomization was performed with 4N Ar gas ejected at a pressure of 00 kg / cm ² . Then, spherical alloy powders having various compositions shown in Table 1 and having an average particle diameter of 25 μm were prepared.

Next, these powders produced were 25 μm or less, 25 to 44 μm, 44 to 63 μm, and 63 μm.
The particles were classified into the above particle sizes, and the amorphous phase was identified by the X-ray diffraction method for the powders having the respective particle sizes. The texture was judged to be amorphous when an amorphous single phase was obtained by the X-ray diffraction method and crystalline when mixed with amorphous and crystalline.

The results are shown in Tables 3 and 4. From Table 3 and Table 4, the alloy powders of Examples 21 to 40 are
Because of the alloy composition according to the present invention and the excellent amorphous forming ability, amorphous alloy powders each having an amorphous single phase were obtained in spherical powders of 63 μm or less. On the other hand, since Comparative Examples 19 to 24 deviate from this composition,
Amorphous single phase was not obtained in the powder having a low amorphous forming ability and a particle size of 44 μm or more. That is, Comparative Examples 19 to
The alloy composition of 24 is Comparative Examples 3, 5, 7, 8, 13 and 1
Although the same as No. 6, in the gas atomization method with a slow cooling rate, an amorphous alloy could not be obtained with a large particle size of the amorphous single-phase powder due to its low amorphous forming ability.

[0028]

[Table 3]

[0029]

[Table 4]

[0030]

INDUSTRIAL APPLICABILITY The biological amorphous alloy of the present invention is an amorphous alloy having excellent strength, corrosion resistance and ability to form an amorphous material, and can be used in various amorphous materials such as hot extrusion and hot pressing. By applying the solidification technique, it can be formed into an amorphous alloy of any shape, and can be applied as a new type of biomedical material to implant materials and medical equipment materials.

(72) Inventor Ken Masumoto, 1-1, Katahira, Aoba-ku, Sendai-shi, Miyagi, Tohoku University Institute for Materials Research (72) Akihisa Inoue, 1-1, Katahira, Aoba-ku, Sendai-shi, Miyagi (72) Inventor Shuji Kamino 23, Uji-kozakura, Uji-shi, Kyoto Prefecture Unitika Central Co., Ltd. (72) Inventor, Kenji Amitani, 23, Uji-kozakura, Uji-shi, Kyoto Unitika-sha, Central Research Company In-house

Claims (1)

[Claims] 1. Compositional formula: Zr _100-abcd MaAlbX
cYd (where M is one element selected from the group consisting of Ti and Hf or a mixture thereof, X is Pt and Pd)
One element or a mixture thereof, Y is C
One element selected from the group consisting of u, Co and Ni or a mixture thereof, a, b, c and d each represent atomic%, 5 ≦ a ≦ 55, 2 ≦ b ≦ 30, 2 ≦ c ≤
45, 5 ≦ d ≦ 40, 20 ≦ a + b + c + d ≦ 80).