JP2016516893A - Zr-based amorphous alloy composition - Google Patents

Abstract

The present invention is a Zr-based amorphous alloy composition that has a higher Zr content than conventional amorphous alloys, consists only of commonly used metal elements, has excellent industrial and economic utility, and is easy to put into practical use. The purpose is to provide goods. According to one aspect of the present invention, Zr is selected from 67 atomic% to 78 atomic%, and any one or more selected from Al and Co is selected from 4 atomic% to 13 atomic%, Cu and Ni. In addition, a Zr-based amorphous alloy composition in which any one or more of 15% to 24% by atom and the amorphous forming ability is 0.5 mm or more is provided.

Description

  The present invention relates to an amorphous alloy composition having high corrosion resistance, and more particularly to a Zr-based amorphous alloy composition having an amorphous forming ability of 0.5 mm or more.

  Amorphous alloys have high strength characteristics of 2 GPa or more, and outstanding characteristics compared to existing crystalline metal materials such as excellent wear resistance, corrosion resistance, and fracture toughness. ing.

  On the other hand, it reacts with nitrogen, which is a reactive gas, in the field of semiconductor manufacturing process, in the production of fine elements such as MEMS, as well as in the field of coating formation for various tools, molds, wear resistance improvement of automotive parts, etc. Development of a multi-component sputtering target using an amorphous alloy based on zirconium capable of forming a high-mild nitride is required. As demand for electric vehicles increases, amorphous materials have attracted attention for improving the corrosion resistance of metal bipolar plates used in polymer electrolyte fuel cells. In the early days, graphite was applied to bipolar plates, but recently, development of metal bipolar plates has been promoted in order to improve economy, strength, and electrical conductivity. However, in the case of metal bipolar plates, it has been pointed out as a problem that the corrosion resistance is low with respect to the operating environment of the fuel cell. Therefore, recently, attempts have been made to improve the corrosion resistance of bipolar plates by manufacturing bipolar plates using amorphous alloy ribbons or coating amorphous plates on metal-based plates. ing. In the case of a Zr-based amorphous alloy, it is known as an alloy system having a high forming ability. Typically, in the case of a Zr-Al-Ni-Cu-based alloy, it is reported that it has an amorphous forming ability of 10 mm or more. Has been. However, in the reported Zr-based amorphous alloys, most of them have a Zr content of 65 atomic% or less, and have an amorphous forming ability in a composition range in which the contents of added Ni and Cu elements are relatively high. It is known to have. As a result, in order to improve wear resistance and corrosion resistance, it is required to develop an alloy system having a high content of Zr constituting an amorphous alloy and a low content of Ni or Cu.

  The present invention is for solving various problems including the above-mentioned problems, and has a higher Zr content than conventional alloys, consisting only of ordinary metal elements, and is excellent in industrial and economical utility. An object of the present invention is to provide a Zr-based amorphous alloy composition having high corrosion resistance that is easy to put into practical use. However, such a problem is exemplary and does not limit the scope of the present invention.

  According to one aspect of the present invention, Zr is selected from 67 atomic% to 78 atomic%, and any one or more selected from Al and Co is selected from 4 atomic% to 13 atomic%, Cu and Ni. In addition, a Zr-based amorphous alloy composition in which any one or more of 15% to 24% by atom and the amorphous forming ability is 0.5 mm or more is provided.

  In the Zr-based amorphous alloy composition, Zr is 67 atomic% to 78 atomic%, Co is 4 atomic% to 12 atomic%, and at least one selected from Cu and Ni is 15 atomic% to It can consist of 24 atomic percent.

  In the Zr-based amorphous alloy composition, Zr is 67 atomic% to 78 atomic%, Al is 3 atomic% to 10 atomic%, Co is 2 atomic% to 9 atomic%, and Cu is 17 atomic% to 23 atomic%. It can consist of

The Zr-based amorphous alloy composition has a casting thickness in the range of 20 μm to 100 μm when the molten alloy composition is cast at a cooling rate in the range of 10 ⁴ K / sec to 10 ⁶ K / sec. It can be an alloy composition from which a crystalline ribbon is obtained.

  The Zr-based amorphous alloy composition may be an amorphous alloy powder or a nanocrystalline alloy powder. The Zr-based amorphous alloy composition may be a foil-like amorphous alloy ribbon or a nanocrystalline alloy ribbon. The Zr-based amorphous alloy composition may be an amorphous alloy casting or a nanocrystalline alloy casting.

  According to another aspect of the present invention, there is provided a bipolar plate for a fuel cell manufactured using an amorphous ribbon having the same composition as the alloy composition described above.

  According to the embodiment of the present invention, it is possible to implement a Zr-based amorphous alloy composition having an amorphous forming ability and a wide supercooled liquid phase region. Furthermore, a sputtering target made of a crystalline alloy embodied by heating the Zr-based amorphous alloy composition in a predetermined temperature range has greatly improved thermal / mechanical stability. The phenomenon of sudden destruction does not occur, and the sputtering process can be performed stably. In addition, since it has a very uniform microstructure, it has the effect of reducing the deviation between the target composition and the thin film composition due to the difference in the sputtering rate of the multi-components constituting the target, depending on the thickness of the thin film The composition uniformity can be ensured.

  In addition, in the case of an amorphous ribbon made of the above amorphous alloy composition, when applied to a bipolar plate of a polymer electrolyte fuel cell stack, the bipolar plate has much better corrosion resistance than a metal plate. Can be manufactured. Of course, the scope of the present invention is not limited by such effects.

FIG. 4 is a Zr—Co— (Ni, Cu) -based ternary phase diagram showing a region where bulk amorphous formation of 0.5 mm or more is confirmed in the alloy composition according to the present invention. FIG. 3 is a Zr— (Al, Co) —Cu based ternary phase diagram according to the present invention. It is the result of having irradiated the amorphous formation ability with respect to a part Example of this invention using X-ray diffraction. The DSC analysis results showing the crystallization characteristics of the examples of the present invention are shown. It is an external appearance of the sputtering target manufactured using the alloy composition which has a composition by Example 2 of this invention. 5 (a) to 5 (d) were observed with an electron microscope around the indenter traces that appeared when the crack generation test proceeded after annealing the Zr-based amorphous alloy composition according to the example of the present invention. It is a result. 6 (a) to 6 (d) are results of observing the microstructure of the crystalline alloy target manufactured from the Zr-based amorphous alloy composition according to the example of the present invention with an electron microscope. It is an amorphous alloy ribbon photograph with a thickness of 70 μm manufactured using the composition of Example 15 of the present invention. 3 is a result of a potentiodynamic polarization test performed in an atmosphere of a fuel cell stack of an amorphous ribbon manufactured using a Zr-based amorphous alloy composition according to an embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and can be embodied in various forms different from each other. The following embodiments complete the disclosure of the present invention, and It is provided to fully inform the trader of the scope of the invention. For convenience of explanation, in the drawings, the size of components can be exaggerated or reduced.

  In the present invention, the term “amorphous” means characteristics of an amorphous phase generally known to those skilled in the art, such as an amorphous structure as a whole and an X-ray diffraction pattern forming a halo shape. Means having For example, the term “amorphous” refers not only to the case where the composition structure is 100% amorphous, but also to the extent that the crystalline is present more than the amorphous structure and loses the amorphous characteristics. Unless it is a thing, the case where a part exists in an amorphous structure by crystalline (or nano crystalline) may also be included. The nanocrystalline alloy means a metal alloy body having an average crystal grain size of less than 100 nm.

In the present invention, the glass forming ability means a relative scale indicating whether an alloy having a specific composition easily becomes amorphous to a certain cooling rate. Generally, in order to form an amorphous alloy through casting, a high cooling rate above a certain level is required, and when used in a casting method having a relatively low solidification rate (for example, a copper mold casting method) The amorphous forming composition range is reduced. On the other hand, a rapid solidification method such as melt spinning, in which a molten alloy is dropped on a rotating copper roll and solidified into a ribbon or wire, has been maximized by 10 ⁴ K / sec to 10 ⁶ K / sec or more. A cooling rate is obtained, and the composition range in which amorphous can be formed is expanded. Therefore, the evaluation of how much amorphous a specific composition has is generally characterized by a relative value depending on the cooling rate of a given cooling step.

Such an amorphous forming ability depends on the alloy composition and the cooling rate, and in general, the cooling rate is inversely proportional to the casting thickness ([cooling rate] 鋳 造 [casting thickness] ⁻² ). Therefore, the amorphous forming ability can be relatively quantified by evaluating the critical thickness of the cast material from which amorphous is obtained during casting. For example, according to the copper mold casting method, it is possible to display the critical casting thickness (diameter in the case of a rod shape) of a cast material from which an amorphous structure is obtained. As another example, when forming a ribbon by melt spinning, it can be indicated by the critical thickness of the ribbon in which the amorphous is formed.

In the present invention, the meaning of the alloy having an amorphous forming ability is that when the molten metal is cast at a cooling rate in the range of 10 ⁴ K / sec to 10 ⁶ K / sec, the casting thickness in the range of 20 μm to 100 μm. Furthermore, it means an alloy from which an amorphous ribbon can be obtained.

  The alloy composition having an amorphous forming ability according to the present invention is composed of multi-components of three or more elements, a difference in atomic radius between main elements is 12% or more, and heat of mixing between the main elements (heat of mixing). Has a characteristic of having a negative value.

  The Zr-based amorphous alloy composition according to an embodiment of the present invention has a composition in which Zr is 67 atomic% to 78 atomic%, any one or more selected from Al and Co is 4 atomic% to 13 atomic%, Any one or more selected from Cu and Ni consists of 15 atomic% to 24 atomic%, and the amorphous forming ability is 0.5 mm or more. For example, the Zr-based amorphous alloy composition according to an embodiment of the present invention may be any one selected from 67 atomic% to 78 atomic%, Co from 4 atomic% to 12 atomic%, Cu and Ni. One or more may consist of 15 atom% to 24 atom%, and the amorphous forming ability may be 0.5 mm or more. As another example, the Zr-based amorphous alloy composition according to an embodiment of the present invention has a Zr of 67 atom% to 78 atom%, Al of 3 atom% to 10 atom%, and Co of 2 atom% to It may be 9 atomic%, Cu may be 17 atomic% to 23 atomic%, and the amorphous forming ability may be 0.5 mm or more.

  On the other hand, the Zr-based amorphous alloy composition according to the embodiment of the present invention has a Zr in the range of 67 atomic% to 78 atomic%, strictly speaking, in the range of 67 atomic% to 76 atomic%, more strictly 67 In the range of 4 atomic percent to 75.7 atomic percent, more strictly in the range of 69.86 atomic percent to 75.7 atomic percent, more strictly in the range of 70.2 atomic percent to 75.7 atomic percent. To be controlled.

  The unit of atomic% mentioned in the present specification means the proportion of the atom in the total alloy composition.

  Examples are provided below to assist in understanding the present invention. However, the following examples are for helping understanding of the present invention, and the present invention is not limited to the following examples.

Table 1 shows the alloy composition, amorphous forming ability (GFA), glass transition temperature (Tg), and crystallization onset temperature (Tx) of the Zr-based amorphous alloy composition according to the embodiment of the present invention. ), Supercooled liquid phase region (ΔT = Tx−Tg), solidus temperature (T _S ), liquidus temperature (T _L ), and the like. For example, the amorphous alloy composition of Example 1 is such that Zr is 67.4 atomic%, Al is 7 atomic%, Co is 3 atomic%, and Cu is 22.6 atomic%, which is Zr _67.4 Al. ₇ Co ₃ Cu _22.6 is displayed (hereinafter, the composition of the alloy is displayed in this manner).

  The inventor has used the Zr-based amorphous alloy composition disclosed in Table 1 as an amorphous alloy casting (amorphous alloy rod), amorphous alloy powder, foil-like amorphous alloy ribbon, etc. Embodied. As an exemplary method for realizing it, a rapid solidification method, a mold casting method, a high-pressure casting method, an atomizing method, and / or a melt spinning method can be used.

  The amorphous alloy casting was manufactured by, for example, a copper mold suction casting method after melting an alloy button having the composition disclosed in Table 1 by arc melting. Generally, the cooling rate of a die casting method such as a copper die suction casting method is lower than that of a melt spinning method, and the alloy having the above composition is an amorphous material as defined in the present invention. Has the ability to form.

  The amorphous alloy powder can be manufactured by an atomizing method. For example, after an alloy having the composition disclosed in Table 1 is melted by an arc melting method, an alloy button is manufactured and a powder manufacturing apparatus is prepared. The alloy button was remelted by high frequency and then the molten alloy was sprayed with argon gas.

  The foil-like amorphous alloy ribbon is manufactured by a melt spinning method. Specifically, an alloy melt is manufactured by an arc melting method in accordance with the composition ratio disclosed in Table 1, and then at a high speed of 700 rpm. The molten alloy was manufactured by rapidly injecting the molten alloy into the surface of a rotating copper roll having a diameter of 600 mm through a nozzle.

  The Zr-based amorphous alloy composition having the composition disclosed in Table 1 has an amorphous forming ability of 0.5 mm or more and a supercooled liquid phase region (ΔT in the range of 11.85 ° C. to 48.55 ° C. ). That is, the present inventor has a high Zr content, that is, Zr is in the range of 67 atomic% to 78 atomic%, strictly, in the range of 67 atomic% to 76 atomic%, more strictly, In the range of 67.4 atomic% to 75.7 atomic%, more strictly in the range of 69.86 atomic% to 75.7 atomic%, more strictly in the range of 70.2 atomic% to 75.7 atomic%. A Zr-based amorphous alloy composition capable of ensuring an excellent amorphous forming ability and a wide range of supercooled liquid phase region while having a range was realized.

  For this purpose, referring to Examples 1 to 3, Example 5 to Example 8, and Examples 10 to 15 disclosed in Table 1, a Zr-based amorphous alloy according to an embodiment of the present invention. In the composition, Zr is 67 atomic% to 78 atomic%, any one selected from Al and Co is 4 atomic% to 13 atomic%, and any one selected from Cu and Ni. The above consists of 15 atomic% to 24 atomic%. Strictly, the Zr-based amorphous alloy composition has a Zr of 67.4 atomic% to 75.7 atomic%, and at least one selected from Al and Co is 4.8 atomic% to 13 Any one or more selected from among atomic%, Cu and Ni may consist of 15.7 atomic% to 23.6 atomic%. In this case, the amorphous forming ability has a range of 0.5 mm to 4 mm.

  FIG. 1A is a state diagram illustrating a Zr-based amorphous alloy region to which Al of the present invention is not added. It is known that when Al is not added, it is difficult to ensure sufficient amorphous forming ability and a wide range of supercooled liquid phase region. Referring to Examples 12 to 15 disclosed in Table 1, the Zr-based amorphous alloy composition according to an embodiment of the present invention does not include Al, and Zr is 67 atomic% to 78 atomic%. Co is 4 atomic% to 12 atomic%, and at least one selected from Cu and Ni is 15 atomic% to 24 atomic%. More strictly, Al is not included, and Zr is 69.86. At least one selected from atomic percent to 75.7 atomic percent, Co from 4.8 atomic percent to 12 atomic percent, and Cu and Ni consists of 15.7 atomic percent to 23.6 atomic percent. It was confirmed that an amorphous forming ability in the range of 0.5 mm to 1 mm and a wide supercooled liquid phase region in the range of 13.33 ° C. to 33.86 ° C. can be secured.

  FIG. 1B is an alloy phase diagram illustrating the Zr— (Al, Co) —Cu based amorphous alloy range of the present invention. In the case where Ni is not added, it is known that sufficient amorphous forming ability and a wide range of supercooled liquid phase regions are difficult to be secured. However, Examples 1, 3 and 5 disclosed in Table 1 are used. Referring to Examples 8 and 10, the Zr-based amorphous alloy composition according to an embodiment of the present invention does not contain Ni, Zr is 67 atomic% to 78 atomic%, and Al is 3 atomic%. 10 atom%, Co 2 atom% to 9 atom%, Cu 17 atom% to 23 atom%, and more strictly, it does not contain Ni and Zr is 67.4 atom% to 70.9 atom%. Al is composed of 3 atomic% to 10 atomic%, Co is composed of 2 atomic% to 9 atomic%, and Cu is composed of 17.1 atomic% to 22.6 atomic%, but has an amorphous forming ability in the range of 1 mm to 4 mm. It was confirmed that a wide supercooled liquid phase region in the range of 15.37 ° C. to 48.55 ° C. can be secured.

  FIG. 2 shows the result of irradiating the amorphous forming ability of some examples of the present invention disclosed in Table 1 using X-ray diffraction.

  Referring to FIG. 2, the Zr-based amorphous alloy compositions according to Example 2, Example 7, Example 12, and Example 15 disclosed in Table 1 are typically represented in an amorphous phase. It can be confirmed that a broad peak is observed and no sharp peak appears. The inventor has confirmed that such a typical broad peak is observed in all examples disclosed in Table 1.

  3 (a) to 3 (d) are DSCs (Differential Differences) showing crystallization characteristics according to Example 2, Example 7, Example 13, and Example 15 of the present invention disclosed in Table 1, respectively. Scanning calorimeter) analysis results are shown sequentially.

  Referring to FIGS. 3 (a) to 3 (d), the alloys of Examples 2, 7, 13, and 15 of the present invention disclosed in Table 1 are used at elevated temperatures. It was confirmed that an exothermic peak due to crystallization behavior was observed. Thereby, it can confirm that the alloy of the Example of this invention has an amorphous phase in at least one part in an alloy.

  The Zr-based amorphous alloy composition according to the embodiment of the present invention is a coating for improving the wear resistance of various tools, molds, and automotive parts as well as manufacturing of microelements such as MEMS in the field of semiconductor manufacturing processes. Can be used in the field of formation. Hereinafter, the case where it is applied to a sputtering target will be described as a specific example.

  The sputtering process is a technique for forming a thin film on the surface of a base material by causing argon ions or the like to collide with a target to which a negative voltage is applied at a high speed to release target atoms and supplying the target material to the base material. When producing an amorphous phase thin film or a nanocomposite thin film containing an amorphous phase by sputtering, an amorphous target can be used. Such an amorphous target is composed of a multi-component metal alloy having a high amorphous forming ability, and the dissimilar metal element separated from the amorphous target forms an amorphous phase on the surface of the base material. An alloy thin film can be formed.

  However, the temperature of such an amorphous target increases due to ion collision during the sputtering process, and the structure near the surface of the target can be changed due to such temperature increase. That is, due to the characteristics of the thermally unstable amorphous phase, when the target temperature increases, local crystallization can proceed on the target surface. Such local crystallization can cause volume change and structural relaxation of the target, thereby increasing the brittleness of the target and can result in the target being easily destroyed during the sputtering process. If the target is destroyed during the process, it becomes a fatal problem for product production. Therefore, it is very important to secure a stable target that does not cause such destruction during the sputtering process.

  The inventor prepares a plurality of the aforementioned Zr-based amorphous alloys (or nanocrystalline alloys), and converts the plurality of amorphous alloys (or nanocrystalline alloys) into the amorphous state. An alloy (or nanocrystalline alloy) is heat-pressed in a temperature range not lower than the crystallization start temperature and lower than the melting temperature, and the average size of the crystal grains is in the range of 0.1 μm to 5 μm (strictly, 0.1 μm Producing a crystalline alloy having a range of 1 μm, more strictly, a range of 0.1 μm to 0.5 μm, and more strictly a range of 0.3 μm to 0.5 μm. The sputtering alloy target made of a crystalline alloy is greatly improved in thermal / mechanical stability, and the target is not destroyed suddenly during the sputtering process, and the sputtering process can be performed stably. I confirmed that I can . In addition, since it has a very uniform microstructure, it has the effect of reducing the deviation between the target composition and the thin film composition due to the difference in the sputtering rates of the multiple components that make up the target. It was confirmed that there was an effect that could be secured. For more details on this, reference may be made to patent application numbers 10-2011-0129888 and 10-2013-0065244 already filed by the inventors of the present application.

  FIG. 4 is an appearance photograph after sputtering of a target manufactured using the amorphous alloy composition of Example 2 disclosed in Table 1 of the present invention. Referring to FIG. 4, the manufactured sputtering target is not observed to be broken during the sputtering process, and the surface after sputtering is not observed to be non-uniform due to the difference in sputtering yield between components. .

  FIG. 5 shows a crack generation test after annealing the Zr-based amorphous alloy compositions according to the compositions of Example 2, Example 7, Example 12, and Example 15 disclosed in Table 1 of the present invention. FIG. 6 is a result of observing the periphery of the indenter appearing with an electron microscope. FIG. 6 shows Zr according to the compositions of Example 2, Example 7, Example 12, and Example 15 disclosed in Table 1 of the present invention. It is the result of having observed the fine structure of the crystalline alloy target manufactured from the base amorphous alloy composition with the electron microscope.

  Referring to FIGS. 5 and 6, the Zr-based amorphous alloy composition according to the embodiment disclosed in Table 1 of the present invention is annealed in a temperature range above the crystallization start temperature of the amorphous alloy and below the melting temperature. The sputtering alloy target thus formed has a crystalline structure in which crystal grains having a size in the range of 0.1 μm to about 5 μm are uniformly distributed, and it can be confirmed that no cracks are generated.

  In addition, the Zr-based amorphous alloy composition according to the embodiment of the present invention is manufactured as an amorphous alloy ribbon and used as a metal bipolar plate used in a polymer electrolyte fuel cell. Hereinafter, the case where it applies to a bipolar plate using an amorphous alloy ribbon is demonstrated as a specific example. In the case of a metal bipolar plate, the characteristics of the fuel cell are lowered due to the low corrosion resistance against the operating environment of the fuel cell. Therefore, recently, attempts have been made to improve the corrosion resistance of bipolar plates by manufacturing bipolar plates using amorphous alloy ribbons or coating amorphous plates on metal-based plates. Yes. As described above, using the method of coating an amorphous film on the surface of a metal bipolar plate using the amorphous alloy target of the present invention, as another example, to replace the currently used stainless steel It is possible to use an amorphous ribbon manufactured using the amorphous alloy of the present invention.

FIG. 7 is a photograph of an amorphous alloy ribbon manufactured using the amorphous alloy composition according to Example 15 of the present invention. FIG. 8 shows an experiment using the amorphous alloy ribbons having the compositions of Example 2, Example 7, Example 12 and Example 15 of the present invention under the same conditions as the polymer electrolyte fuel cell stack environment. It is a result of a potentiodynamic polarization test. The potentiodynamic polarization test was performed in a potential range of −0.6 V to 1.2 V using a 1M H ₂ SO ₄ +2 ppm HF solution. Table 2 summarizes the results of potentiodynamic polarization experiments on amorphous ribbons with different alloy compositions.

According to Table 2, the corrosion current density is measured at 5.60 × 10 ⁻⁵ A / cm ² in the case of the stainless steel plate currently used as the metal bipolar plate material, while the Zr group of the present invention is measured. In the case of an amorphous alloy ribbon, it was confirmed that a corrosion current density of 1.78 × 10 ⁻⁸ A / cm ² was obtained. This proves that the corrosion characteristics of the amorphous alloy ribbon of the present invention are very excellent compared to the stainless steel plate.

  FIG. 8 is a graph illustrating the results of a potentiodynamic polarization test measured using amorphous alloy ribbons of the compositions of Example 2, Example 7, Example 12, and Example 15 of the present invention. In the case of a stainless steel plate, it was confirmed that a corrosion phenomenon due to a hyperpassive reaction occurred at a corrosion potential of 1.0 V, which is the operating environment of the fuel cell stack, but in the case of an amorphous alloy ribbon according to an embodiment of the present invention. It can be confirmed that no further corrosion occurs after the passive reaction at a corrosion potential in the range of 0.6 to 1.2 V, which is the operating environment of the fuel cell stack. Therefore, it can be seen that the amorphous ribbon using the amorphous alloy composition of the present invention has excellent corrosion resistance in the environment where the fuel cell stack is used.

  Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely illustrative, and various modifications and equivalent other embodiments can be made by those skilled in the art. You will understand that. Therefore, the true technical protection scope of the present invention should be determined by the technical idea of the claims.

  The present invention is applicable to technical fields related to Zr-based amorphous alloy compositions.

Claims (5)

  Zr is 67 atom% to 78 atom%, any one or more selected from Al and Co is 4 atom% to 13 atom%, and any one or more selected from Cu and Ni is 15 atoms A Zr-based amorphous alloy composition comprising about 24 to 24 atomic% and having an amorphous forming ability of 0.5 mm or more.   In the composition, Zr is 67 atom% to 78 atom%, Co is 4 atom% to 12 atom%, and at least one selected from Cu and Ni is 15 atom% to 24 atom%. Item 2. The Zr-based amorphous alloy composition according to Item 1.   2. The composition according to claim 1, wherein the composition comprises 67 atomic% to 78 atomic% of Zr, 3 atomic% to 10 atomic% of Al, 2 atomic% to 9 atomic% of Co, and 17 atomic% to 23 atomic% of Cu. The Zr-based amorphous alloy composition described. When the alloy composition is cast at a cooling rate in the range of 10 ⁴ K / sec to 10 ⁶ K / sec, an amorphous ribbon is obtained in a casting thickness in the range of 20 μm to 100 μm. The Zr-based amorphous alloy composition according to any one of claims 1 to 3, which is an alloy composition to be obtained.   The bipolar plate for a fuel cell according to any one of claims 1 to 3, wherein the bipolar plate is manufactured using an amorphous ribbon having the same composition as the alloy composition.