KR20050000246A - Cu-based Amorphous Alloy Composition - Google Patents

Abstract

PURPOSE: To provide a Cu-based amorphous alloy which increases amorphization efficiency, offers a possibility of application as structural material for copper alloy due to great increase of strength and is commercialized more easily by adding a fifth element to a conventional Cu-Ni-Zr-Ti quaternary amorphous alloy, thereby improving glass forming ability. CONSTITUTION: The Cu-based amorphous alloy composition is characterized in that it is represented as a general formula: $û(Cu+Ni)x(Ti+Zr)y$ý100-(a+b)(M1,M2)a(M3)b, wherein x, y, a and b satisfy 39<=x<=71, 29<=y<=61, 0<=a<=10 and 0<=b<=5 as atom% respectively provided that a and b are not 0 at the same time; M1 is Y, Nb, Co or Ag as a metal element; M2 is Al, In or Sn as an amphoteric element; and M3 is P, B or Si as a nonmetal element.

Description

Cu-based Amorphous Alloy Composition

The present invention relates to a copper-based amorphous alloy, and more particularly, to bulking with a superior amorphous forming ability by adding a metal element, an amphoteric element or a non-metal element as a fifth element to a quaternary alloy of Cu-Ni-Zr-Ti. It relates to a possible copper-based amorphous alloy.

In general, copper is a metal with a unique red gloss, which is not only excellent in malleability, ductility, and workability, but also in strength, and has the second highest conductivity of heat and electricity after silver.

Copper is not only itself, but also widely used as an alloy such as brass, bronze, aluminum bronze, beryllium copper, and is particularly used as a new product for electric wires. Electric wire is processed into various electric wires by melting electrolytic copper and using hardened rods. In addition, new copper products are prepared by mixing and dissolving electrolytic copper and other alloy metals, scrap metals, copper alloys, and the like appropriately, and then processing them into plates, rods, pipes, wires, etc., using the ingots injected as raw materials. The copper plate is also used for making general household appliances, and bronze is mixed with 2-10% tin.

However, copper has a relatively low strength for use as a structural material and does not oxidize in pure dry air, but rusts due to moisture in ordinary air, mainly producing cyan.

Thus, this reactivity and low strength of copper are constrained by the wider use of copper.

The amorphous metal material has much higher tensile strength than the crystalline metal material, and is also known to be excellent in toughness and corrosion resistance. Thus, when bulking copper amorphous alloys, there is a possibility that the amorphous metal material can be widely used by improving the strength and reducing the reactivity.

Thus, looking at the copper-based amorphous alloys developed to date, binary alloys such as Cu-M (M = Ti, Zr or Hf), Cu-Mg-Ln (Ln = La, Sm, Eu, Tb, Er or Lu) , Ternary alloys such as Cu-Zr-Ti and Cu-Hf-Ti, and ternary alloys such as Cu-Zr-Hf-Ti, Cu-Zr-Ti-Y and Cu-Ti-Zr-Ni. Can be.

However, such conventional copper-based amorphous alloys can only be amorphous in the form of ribbons or powders, most of which are about tens of micrometers thick using rapid solidification, and recently developed copper-based bulk amorphous alloys are generally 3mm. Has a bulk amorphous maximum diameter of less than the practical use was limited.

Accordingly, the present invention is to solve the problems of the prior art, the object of the bulk amorphous by adding a fifth element to the conventional Cu-Ni-Ti-Zr quaternary amorphous alloy to improve the amorphous forming ability The present invention aims to provide a copper-based amorphous alloy, which is more efficient, suggests the applicability of a copper alloy as a structural material due to a large increase in strength, and which is easier to use.

Figure 1a is a copper-based amorphous alloy composition prepared according to the present invention was prepared by Cu ₄₇ Ti ₃₃ Zr ₁₁ Ni ₈ Si ₁ and analyzed using a differential thermal analyzer,

Figure 1b is a result of the copper-based amorphous alloy composition prepared according to the present invention prepared by Cu ₄₇ Ti ₃₃ Zr ₁₁ Co ₈ Si ₁ and analyzed using a differential thermal analyzer,

Figure 1c is a copper-based amorphous alloy composition prepared according to the present invention prepared by Cu ₄₇ Ti ₃₃ Zr ₁₁ In ₈ Si ₁ and analyzed using a differential thermal analyzer,

Figure 1d is a result of the copper-based amorphous alloy composition prepared according to the present invention prepared by Cu ₄₇ Ti ₃₃ Zr ₁₁ Sn ₈ Si ₁ and analyzed using a differential thermal analyzer,

2A is a differential thermal analysis of the bulk amorphous behavior of Cu ₄₇ Ti ₃₄ Zr ₁₁ Ni ₈ alloy;

2b is a differential thermal analysis of the bulk amorphous behavior of Cu ₄₇ Ti ₃₃ Zr ₁₁ Ni ₈ Si ₁ alloy;

FIG. 3A is an X-ray diffraction analysis of a 4 mm rod-shaped specimen of Cu ₄₇ Ti ₃₃ Zr ₁₁ Ni ₈ Si ₁ alloy.

3B is a transmission electron microscope analysis of 4 mm rod-shaped specimens of Cu ₄₇ Ti ₃₃ Zr ₁₁ Ni ₈ Si ₁ alloy,

4 is a differential thermal analysis of bulk amorphous behavior of Cu ₄₇ Ti ₃₃ Zr ₁₁ Ni ₆ Sn ₂ Si ₁ alloy;

5 is a hardness test result of the copper commercial alloy (Cu-Sn- (Ti, Cr)) and the copper-based amorphous alloy composition according to the present invention.

In order to achieve the above object, according to the present invention, the general formula {(Cu + Ni) _x (Ti + Zr) _y } _{100- (a + b)} (M ₁ , M ₂ ) _a (M ₃ ) _b Where x, y, a and b are atomic%, satisfying 39≤x≤71, 29≤y≤61, 0≤a≤10 and 0≤b≤5, respectively, provided that a, b should not be 0 at the same time), and M ₁ is Y, Nb, Co or Ag as a metal element, M ₂ is Al, In or Sn as an amphoteric element, and M ₃ is P, It provides a copper-based amorphous alloy composition, characterized in that B or Si.

In general, an amorphous alloy may have excellent amorphous forming ability by combining a multicomponent system having three or more components, a large atomic radius difference of 10% or more, and atoms having negative mixed heat, and the lower the melting temperature of the alloy, the more amorphous formation. The rule of thumb for this is known.

In the case of the amorphous alloy that satisfies the above empirical rules, it is possible to have a unique amorphous structure that is very densely packed through the new atomic arrangement partially and a long period uniformity of strong bonding atoms. Under such a structure, the atomic diffusivity is reduced and excellent amorphous forming ability is realized through suppression of nucleation and growth of the crystal phase from the liquid phase.

With this in mind, the present inventors selected copper-based Cu-Ni-Zr-Ti quaternary copper alloys composed of titanium, zirconium and nickel as the basic composition.

In the above, Cu and Ni, and Ti and Zr may be considered as a bundle in designing alloys respectively as a solid solution.

In the present invention, the Cu-Ni-Zr-Ti composition is basically selected in the quaternary alloy region capable of amorphous formation, where x is 39 atomic%, y is less than 9 atomic%, the dense filling effect given in the multi-component alloy Since it is not possible to obtain excellent amorphous, it is inappropriate to form, and when x exceeds 71 atomic percent and y exceeds 61 atomic percent, it is greatly deviated from the quaternary process composition of Cu-Ni-Zr-Ti. Difficulties in achieving low melting temperatures, which are important factors for improvement, are not suitable for good amorphous formation.

In addition, in the present invention, the multi-componentization condition was satisfied by adding a fifth element to the Cu-Ni-Zr-Ti alloy, wherein M ₁ of the added fifth element is a metal element of Y, Nb, and Co. Or Ag, M ₂ is Al, In or Sn as an amphoteric element, and M ₃ is P, B or Si as a nonmetallic element.

And Y (-148 KJ / g-at, -161 KJ / g-at), Nb (-10 KJ / g-at, -143 KJ / g-at), Al (-38 KJ / g-at, -96 KJ / g-at) has a large negative mixed heat value with Cu-Ni, Co (-138 KJ / g-at, -115 KJ / g-at), Ag (-112 KJ / g-at) , -60KJ / g-at), IN (-121 KJ / g-at, -62 KJ / g-at), Sn (-201 KJ / g-at, -139 KJ / g-at) is Zr-Ti It has a large negative mixing heat value and is suitable for good amorphous formation factors.

In addition, nonmetallic elements P, B or Si are generally added by the rule of thumb that metal-nonmetallic pairs are easy to form amorphous.

In addition, in (M ₁ , M ₂ ) _a and (M ₃ ) _b , a and b are limited to atomic% by 0 ≦ a ≦ 10 and 0 ≦ b ≦ 5, because a and b are each 10 atomic%, If it exceeds 5 atomic%, the filling structure of the quaternary alloy is largely out of order. Therefore, it is contrary to the dense filling effect given in the multicomponent system, and is inappropriate to form bulk amorphous. Therefore, there is a limit in forming a better amorphous forming ability.

(Example)

Hereinafter, the present invention will be described in detail with reference to Examples.

First, a metal element (Y, Nb, Co or Ag), an amphoteric element (Al, In or Sn), and a nonmetallic element (P, B or Si) were added to a quaternary copper alloy composition of Cu-Ni-Zr-Ti. Each mixture was mixed as in the atomic% shown in Table 1 to obtain a mixture, and a copper-based bulk amorphous alloy composition in the form of rod was prepared by injection casting.

In the injection casting method used in the present invention, after the mixture is charged into a transparent quartz tube, the vacuum in the chamber is adjusted to about 20 cmHg, and the mixture is dissolved by high frequency induction heating in an argon atmosphere of about 7 to 9 kPa. It is maintained in the quartz tube by the surface tension, and the quartz tube is rapidly lowered before the reaction with the quartz tube, and about 50 kPa of argon gas is injected into the quartz tube to fill the water-cooled copper mold. The rod-shaped specimens with a constant length of 40mm were prepared by varying the diameter to 1-6mm.

The glass transition temperature T _g (glass transition temperature) and the crystallization temperature T _x (Crystallization temperature) of the copper-based amorphous alloy prepared by the method described above using a differential thermal analysis device (DSC) as shown in FIG. 2. Melting temperature (T _m ) was measured using DTA. Based on the results measured in this way, the values of supercooled liquid region (ΔT _x ) = T _x -T _g and reduced glass transition temperature (T _rg ) = T _g / T _m were calculated. It is a representative factor for evaluating the forming ability.

Bulk forming the maximum diameter value of d _max value is compared to the amount of heat generated in the manufacture of rod-shaped specimens been made of a ribbon-like specimen with a differential thermal analyzer, and, X- ray diffraction patterns showed that the characteristic halo pattern of an amorphous alloy (halo pattern It shows the maximum bulk amorphous diameter in each composition through the confirmation of having a), which can be said to be a factor directly proportional to the ability to form amorphous, and the results measured as described above are shown in Table 1.

division Alloy composition (at%) T _g T _x ΔT _x T _rg d _max (mm) Example Cu ₄₇ Ti ₃₃ Zr ₁₁ Ni ₈ Si ₁ 720 757 37 0.56 ≥ 4 Cu ₄₅ Ti ₃₄ Zr ₁₁ Ni ₈ P ₂ 723 765 42 0.56 ≥ 2 Cu ₄₄ Ti ₃₄ Zr ₁₁ Ni ₈ B ₃ 738 763 25 0.57 ≥ 2 Cu ₄₇ Ti ₃₄ Zr ₁₀ Y ₁ Ni ₈ Si ₁ 713 754 41 0.55 ≥ 3 Cu ₄₇ Ti ₃₄ Zr ₈ Nb ₃ Ni ₈ Si ₁ 723 764 41 0.56 ≥ 5 Cu ₄₇ Ti ₃₃ Zr ₁₁ Ni ₆ Co ₂ Si ₁ 724 767 43 0.56 ≥ 3 Cu ₄₇ Ti ₃₃ Zr ₁₁ Ni ₆ Ag ₂ Si ₁ 697 735 38 0.55 ≥ 2 Cu ₄₇ Ti ₃₃ Zr ₁₁ Ni ₆ Al ₂ Si ₁ 715 754 39 0.56 ≥ 3 Cu ₄₇ Ti ₃₃ Zr ₁₁ Ni ₆ In ₂ Si ₁ 717 757 40 0.61 ≥ 5 Cu ₄₇ Ti ₃₃ Zr ₁₁ Ni ₆ Sn ₂ Si ₁ 720 765 45 0.62 ≥ 6 Comparative example Cu ₆₀ Zr ₂₀ Ti ₁₀ Ni ₁₀ 762 <1 Cu ₄₂ Ti ₃₁ Zr ₁₀ Ni ₇ Si ₁₀ 760 <1 Cu ₄₇ Ti ₃₃ Nb ₁₁ Ni ₈ Si ₁ 732 <1 Cu ₄₇ Ti ₃₀ V ₃ Zr ₁₁ Ni ₈ Si ₁ 728 757 19 0.55 <2

In general, it is evaluated that the bulk formation ability is excellent when the amorphous formation ability is directly represented by the d _max value.

However, looking at the results of Table 1, when looking at the embodiment of the present invention, the d _max value is typically at least 2mm in Cu ₄₇ Ti ₃₃ Zr ₁₁ Ni ₆ Ag ₂ Si ₁ composition, Cu ₄₇ Ti ₃₃ Zr ₁₁ Ni ₆ Sn Measured up to 6 mm in ₂ Si ₁ composition it can be seen that the alloy composition of the present invention exhibits an excellent bulk amorphous forming effect.

On the other hand, in the comparative example, Cu ₆₀ Zr ₂₀ Ti ₁₀ Ni _{10 which} is not a composition according to the present invention, which is a conventional basic quaternary system, and Cu ₄₂ in which (M ₃ ) _b deviates from 0≤b≤5 in general formula conditions of the present invention. Ti ₃₁ Zr ₁₀ Ni ₇ Si ₁₀ , Cu ₄₇ Ti ₃₃ Nb ₁₁ Ni ₈ Si _{1 in} which (M ₁ , M ₂ ) _a deviates from 0 ≦ _a ≦ ₁₀ in general formula conditions of the present invention, and the present invention. In the results of Cu ₄₇ Ti ₃₀ V ₃ Zr ₁₁ Ni ₈ Si ₁ added with elements other than the element, the d _max value is less than 2 mm, indicating that the bulk amorphous forming ability is significantly decreased.

In addition, when the copper-based amorphous alloy composition of the present invention is analyzed using a differential thermal analyzer, a supercooled liquid region section known to represent an amorphous forming ability is shown throughout the entire composition region as shown in FIGS. 1A, 1B, 1C, and 1D. It is confirmed that the T _rg value, which is 20 K or more and represents another amorphous formation ability, also has a value of 0.55 or more, which is a value generally given in an alloy having excellent amorphous formation ability.

X-ray diffraction analysis of 4 mm rod-shaped specimens of Cu ₄₇ Ti ₃₃ Zr ₁₁ Ni ₈ Si ₁ alloy showed halo patterns for typical amorphous phases as shown in FIGS. 3A and 3B. This result is also consistent with the result of FIG. 2B.

In addition, the bulk amorphous behavior of the Cu ₄₇ Ti ₃₃ Zr ₁₁ Ni ₆ Sn ₂ Si ₁ alloy in which Ti is substituted by Si 1at% and Ni by Sn 2at% in the Cu ₄₇ Ti ₃₄ Zr ₁₁ Ni ₈ alloy composition is illustrated in FIG. 4. You can check As can be seen from the differential thermal analysis results of FIG. 4, in the case of the alloy composition of the present invention, a good bulk amorphous phase was formed up to 6 mm, which is also consistent with the results of X-ray diffraction analysis and transmission electron microscope analysis.

As a result, it was possible to confirm the excellent bulk amorphous for the alloy composition of the present invention, the results of the hardness difference when compared to the commercial copper alloy copper-based amorphous alloy according to the present invention as shown in Figure 5 It can be seen that the composition has a hardness value of more than five times, the yield strength value calculated through the hardness test value was also confirmed to have a very good strength of about 2GPa.

These results are contrary to the low strengths of existing copper alloys, suggesting the potential applicability of the structural materials of the alloy compositions of the present invention in the future.

As described above, the copper-based amorphous alloy according to the present invention has a superior amorphous forming ability by adding a metal element, an amphoteric element or a nonmetallic element as a fifth element to a quaternary alloy of Cu—Ni—Zr—Ti. Due to the large increase in strength through the bulk amorphous of the alloy, there is an effect that the infinite availability as a structural material, such as copper alloy, high productivity and practical use more easily.

In particular, according to the present invention, the alloy composition of the present invention satisfies the generally known rule of thumb for the improvement of excellent amorphous forming ability and suggests many possibilities for the amorphousization of other alloy systems based on the present invention.

Claims (1)

Formula {(Cu + Ni) _x (Ti + Zr) _y } _{100- (a + b)} (M ₁ , M ₂ ) _a (M ₃ ) _b , wherein x, y, a and b Are atomic%, satisfying 39≤x≤71, 29≤y≤61, 0≤a≤10 and 0≤b≤5 (but a and b are not to be zero at the same time), In addition, M ₁ is Y, Nb, Co or Ag as a metal element, M ₂ is Al, In, or Sn as an amphoteric element, M ₃ is a copper-based amorphous alloy composition, characterized in that as a non-metal element P, B or Si.