CN102418053A - Zr-Cu-Ni-Al amorphous alloy added with trace boron and preparation method thereof - Google Patents

Abstract

The invention provides a Zr-Cu-Ni-Al amorphous alloy added with trace boron and a preparation method thereof, wherein the component expression of the amorphous alloy is Zr_aCu_bAl_cNi_dB_eThe alloy is prepared by arc melting high-purity metal materials of elements into master alloy, cutting the master alloy into a volume weight required by a copper mold, cleaning, placing a master alloy sample in a suction casting crucible, sucking the master alloy sample into the copper mold after melting, filling air, and finally discharging the copper mold. The obtained amorphous alloy has the advantages of low cooling rate, large size, high hardness, good thermal stability, wider supercooled liquid region and good amorphous forming capability.

Description

Zr-Cu-Ni-Al amorphous alloy with trace amount of boron added and preparation method thereof

technical field

The invention belongs to the field of amorphous alloys, in particular to a Zr-Cu-Ni-Al amorphous alloy added with a trace amount of boron and a preparation method thereof.

Background technique

Amorphous alloy refers to an alloy in which the three-dimensional space of its atoms is topologically disordered in a solid state and maintains this state relatively stable within a certain temperature range, also known as metallic glass (Metallic Glass). Due to ultra-rapid solidification, when the alloy is solidified, the atoms have no time to arrange and crystallize in an orderly manner, and there are no grains, grain boundaries and dislocation defects of the crystalline alloy, so it presents excellent comprehensive physical, chemical and mechanical properties. The earliest metals and alloys used by people are crystalline materials. In 1937, German physicist Kramer first prepared amorphous Sb thin film by evaporation deposition method. In 1950, Brenner et al. prepared Ni-P amorphous state by electrodeposition method. alloy. In the late 1950s, Professor Turnbull of Harvard University in the United States first proposed the idea of using the method of deep supercooling of the melt to prepare amorphous alloys. In the early 1960s, Professor Duwez of the California Institute of Technology invented the spray gun and the piston device, and for the first time used the supercooled melt quenching method (cooling rate up to 105K/s) to prepare the Au75Si25 amorphous alloy film. Since then, amorphous alloys have attracted widespread attention. During the nearly 30 years from the early 1960s to the end of the 1980s, due to the restriction of the cooling rate, the prepared amorphous alloys were limited to thin strips, filaments, or powders. shape, thus limiting the application of amorphous alloys, especially as engineering structural materials. In 1974, Chen used the vacuum suction casting method to prepare a Pd-Cu-Si ternary amorphous alloy with a size of millimeters and a critical cooling rate lower than 103K/s. Since then, the era of bulk amorphous (Bulk Metallic Glass) has come. The so-called bulk amorphous alloy refers to an amorphous alloy with high amorphous forming ability (GFA) and low critical cooling rate Rc. Its three-dimensional space size is uniform Greater than 1mm. In 1982, Turnbull used the boron oxide wrapping method to avoid heterogeneous nucleation, and successfully prepared a Pd-Ni-P bulk amorphous alloy with a diameter of 10mm. The critical cooling rate was in the range of 10K/s, but the prepared bulk amorphous alloy Alloys are limited to noble metal systems such as Pd. In the late 1980s, Japan's Inoue broke through the limitation of cooling rate through the method of multi-element alloying, and prepared bulk amorphous alloys composed of non-noble metals (such as: La-Al-Ni and La-Al-Cu[10 ]). In 1993, Johnson in the United States successfully prepared a Zr-Ti-Cu-Ni-Be bulk amorphous alloy with a high glass forming ability, and the critical size reached 14mm. Subsequently, Professor Inoue used the water quenching method to prepare a Pd-Ni-Cu-P bulk amorphous alloy with a critical diameter of 72mm, and the critical cooling rate reached 0.1K/s. Since then, bulk amorphous alloys have attracted much attention in the field of materials and condensed matter physics. Many new alloys of deep supercooled bulk amorphous alloys have been prepared, such as: Ti-based, Hf-based, Fe-based, Pd-Fe-based , Co-based, Cu-based, Zr-based, etc. Great progress has been made in researches on the formation ability, structure, performance, stability and application of bulk amorphous alloys.

Since Inoue et al. summed up three principles for obtaining bulk amorphous alloys, breakthroughs have been made in the preparation and performance research of bulk amorphous alloys. There are three main reasons for the nucleation of large amorphous alloys when they are cooled: (1) the impurities brought in from the raw materials serve as the core of heterogeneous nucleation; The oxide inclusions formed by the reaction in the oxidizing atmosphere; (3) The cooling rate is not large enough to cause the formation of primary crystal nuclei and even grains. Therefore, in the preparation of bulk amorphous alloys, the key is to suppress the heterogeneous nucleation of the alloy during cooling and to increase the cooling rate as much as possible to reduce the incubation time of homogeneous nuclei. In order to reduce the nucleation of amorphous alloys, strict inert gas protection is required for the melting of metals. Impurities in the melt and the inner surface of the container will play a role in heterogeneous nucleation, so purification and slagging during smelting are also extremely important. According to the principle proposed by Inoue to obtain an alloy system with high amorphous forming ability, the composition of the alloy will mainly determine the amorphous forming ability. By choosing an appropriate alloy system, amorphous alloys can be obtained at lower cooling rates. But for the same alloy system, choosing an appropriate preparation method will obtain larger samples.

At present, the preparation methods of bulk amorphous alloys can be divided into direct solidification method and powder consolidation forming method. The direct solidification method mainly includes: water quenching method, copper mold casting method, suction casting method, powder metallurgy technology, argon arc furnace melting method, one-way melting method, etc.

The water quenching method is to seal the ingredients of the bulk amorphous alloy in a vacuumed quartz tube, and then water quench and cool after heating to obtain a bulk amorphous alloy. If there is a high melting point composition in the alloy, it can be mixed in an argon arc furnace to form an alloy and then packaged into a quartz tube. The advantage of this method is that the equipment investment is small, the department that encapsulates the quartz tube is easy to find, and it is easy to obtain a large cylindrical bulk amorphous rod. The disadvantage is that the quartz tube must be sealed every time an amorphous sample is prepared, and the quartz tube will be destroyed during quenching.

The argon arc furnace smelting method is to directly smelt amorphous products by using an argon arc furnace after mixing the components. This method can only refine amorphous samples with small size, and the shape of amorphous samples is generally button-shaped, which is not easy to process and shape. In addition, this method has high requirements on the amorphous forming ability of the alloy system, otherwise the sample or the center of the sample cannot form amorphous, and sometimes the bottom of the sample and the crucible in direct contact with the crucible is not completely melted, which can become the core of the crystal phase and formation, and is also prone to occur. crystalline phase.

The powder metallurgy method utilizes the characteristic that the effective viscosity of the amorphous solid decreases significantly in the supercooled liquid phase region ΔT _x , and a certain pressure is applied to make the material undergo uniform rheology, thereby recombining into a block. The bulk amorphous alloy prepared by powder metallurgy should not only be dense, but also avoid crystallization. The bulk materials of fabricated devices are very limited in terms of purity, density, size and shape.

Contents of the invention

In order to solve the above-mentioned technical problems, the present invention provides a Zr-Cu-Ni-Al amorphous alloy with a trace amount of boron and a preparation method thereof. The amorphous alloy has low cooling rate, large size, high hardness, good thermal stability, and Wide supercooled liquid phase region, good amorphous formation ability.

The technical scheme of the present invention is: a kind of Zr-Cu-Ni-Al amorphous alloy that adds trace amount of boron, and its compositional expression is ZraCubAlcNidBe, and described a, b, c, d, e are the atoms of each element in the alloy. Percentage, where a=50%, b=24~30%, c=10%, d=10%, e=0~6%, a+b+c+d+e=100%.

The preferred scheme of the above-mentioned Zr-Cu-Ni-Al amorphous alloy with a trace amount of boron added is: a=50%, b=28%, c=10%, d=10%, e=2%.

The preferred scheme of the above-mentioned Zr-Cu-Ni-Al amorphous alloy with a trace amount of boron added is: a=50%, b=26%, c=10%, d=10%, e=4%.

The preferred scheme of the above-mentioned Zr-Cu-Ni-Al amorphous alloy with a trace amount of boron added is: a=50%, b=24%, c=10%, d=10%, e=6%.

A method for preparing the above-mentioned Zr-Cu-Ni-Al amorphous alloy with a trace amount of boron added, the steps are as follows: high-purity metal materials of Zr, Cu, Ni, Al elements are arc smelted under an argon atmosphere purified by titanium Then use the EDM wire to cut the master alloy into the required volume and weight of the copper mold. After cutting, put it into a beaker containing 97% alcohol and put it into an ultrasonic cleaning instrument for cleaning. Put the cleaned master alloy sample in In the suction-casting crucible, repeat the previous steps until the master alloy sample is melted, suck it into the copper mold, fill it with air, open the furnace door to clean the crucible, and finally remove the copper mold, that is, add a trace amount of boron to the copper mold Zr-Cu-Ni-Al amorphous alloy.

The beneficial effect of the present invention is that: the Zr-Cu-Ni-Al amorphous alloy added with a trace amount of boron provided by the present invention has the advantages of low cooling rate, large size, high hardness, good thermal stability, and wide The cold liquid phase area, its preparation method integrates the arc melting alloy technology and the copper mold casting technology, which not only utilizes the advantages of no pollution and good uniformity of the arc melting alloy, but also uses the suction casting technology The advantages of fast cooling, especially this technology enables the alloy melting, filling and solidification process to be completed in a vacuum chamber through one vacuum pumping, which belongs to a short-process preparation method.

The copper mold casting method adopted in the present invention is to set a water-cooled copper mold under the heating device, and after the amorphous alloy component is melted, it enters the water-cooled copper mold to be cooled by suction casting or other methods to form an amorphous. Although this method requires special equipment, it can prepare larger-sized amorphous samples due to its high cooling rate, and can prepare amorphous samples of different shapes with different molds, and can also prepare amorphous samples with complex shapes. Copper mold casting, especially with suction casting devices, is widely used because of these advantages.

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Description of drawings

Fig. 1 is the X-ray diffraction spectrum of the amorphous alloy in each embodiment.

Figure 2 is the shear band morphology of the alloy described in Example 1.

Figure 3 is the shear band morphology of the alloy described in Example 2.

Figure 4 is the shear band morphology of the alloy described in Example 3.

FIG. 5 is a stress-strain curve diagram of the amorphous alloys of various embodiments during compression.

Detailed ways

Example 1

A Zr-Cu-Ni-Al amorphous alloy with a trace amount of boron added, its composition expression is: Zr _a Cu _b Al _c Ni _d B _e , where a, b, c, d, e are atomic percentages, a= 50%, b= 28%, c= 10%, d= 10%, e=2%, a+b+c+d+e=100%, its X-ray diffraction spectrum is shown in the top waveform in Fig. 1 The shape of the shear band is shown in Figure 2, and the stress-strain curve during compression is shown in Figure 5 as the marked 3 line. Its preparation method is as follows: take the rod, block or powder material of pure metal Zr, Cu, Ni and Al at the above atomic percentage, and first arc melt it in an argon atmosphere purified by titanium, and the alloy needs to be smelted several times To ensure the uniformity of the composition. Then use electric discharge wire to cut the master alloy to meet the volume and weight requirements of different molds, put the cut materials into a beaker filled with 97% alcohol, and put them together in an ultrasonic cleaning instrument for cleaning for 1 minute. Put the cleaned master alloy sample in the suction casting crucible, repeat the previous steps, press the suction casting button after the master alloy sample is melted, and suck it into the mold. Then fill in the air, open the furnace door to clean the crucible, remove the copper mold (the mold size is Φ5*75mm), and take out the Zr-Cu-Ni-Al amorphous alloy with trace boron added in the copper mold. After the master alloy sample is melted and cooled at a cooling rate greater than 100°C/s, an amorphous material can be formed, and the volume percentage of the amorphous phase is not less than 50%.

Example 2

The only difference between this embodiment and embodiment 1 is that a=50%, b=26%, c=10%, d=10%, e=4%. Its X-ray diffraction spectrum is shown in the waveform in the middle of Fig. 1, its shear band morphology is shown in Fig. 3, and the stress-strain curve during compression is shown in Fig. 5 as marked 4 lines. Its preparation method is identical with embodiment 1.

Example 3

The only difference between this embodiment and embodiment 1 is that a= 50%, b= 24%, c= 10%, d= 10%, e=6%, a+b+c+d+e=100 %. Its X-ray diffraction spectrum is shown in the waveform at the bottom of Fig. 1, its shear band morphology is shown in Fig. 4, and the stress-strain curve during compression is shown in Fig. 5 as marked 2 lines. Its preparation method is identical with embodiment 1.

A small amount of impurities such as oxygen, nitrogen, phosphorus, etc. are allowed to exist in the Zr-Cu-Ni-Al amorphous alloy with a trace amount of boron added by the present invention. The impurity elements mainly come from the starting materials, the atmosphere in the alloy smelting process, and Impurities, etc. Some elements occupying a small proportion may have an impact on the performance of the amorphous alloy, such as the oxygen content has a greater impact on the glass-forming ability of the alloy. The main element Zr of the alloy provided by the present invention is a very active element, and it can be mixed with gases such as oxygen. Impurity elements have a strong affinity, therefore, the existence of a small amount of oxides can still ensure that the alloy has a good glass-forming ability, but the oxygen content in the alloy should not exceed 0.1% (weight ratio).

Claims (6)

1.1 a Zr-Cu-Ni-Al non-crystaline amorphous metal that adds trace B is characterized in that: its composition expression formula is Zr _aCu _bAl _cNi _dB _e, said a, b, c, d, e are the shared per-cent of each element atom in the alloy, a=50% wherein, b=24 ~ 30%, c=10%, d=10%, e=0 ~ 6%, a+b+c+d+e=100%.

2. the Zr-Cu-Ni-Al non-crystaline amorphous metal of interpolation trace B according to claim 1 is characterized in that: a=50%, and b=28%, and c=10%, and d=10%, e=2%.

3. the Zr-Cu-Ni-Al non-crystaline amorphous metal of interpolation trace B according to claim 1 is characterized in that: a=50%, and b=26%, and c=10%, and d=10%, e=4%.

4. the Zr-Cu-Ni-Al non-crystaline amorphous metal of interpolation trace B according to claim 1 is characterized in that: a=50%, and b=24%, and c=10%, and d=10%, e=6%.

5. the preparation method of the Zr-Cu-Ni-Al non-crystaline amorphous metal of the said interpolation trace B of claim 1; Its step is following: the high purity metal material of Zr, Cu, Ni, Al element arc melting under through the argon gas atmosphere of titanium purifying is become mother alloy, cut into the required volume weight of copper mold to mother alloy with wire electric discharge, put into the beaker of Sheng 97% alcohol behind the well cutting and clean at the ultrasonic cleaning instrument; Mother alloy sample after cleaning is placed in the crucible of inhaling casting; To the mother alloy sample melted, it is sucked in the copper mold, charge into air, open the fire door cleaning crucible; At last copper mold is unloaded, promptly get the Zr-Cu-Ni-Al non-crystaline amorphous metal that adds trace B in the copper mold.

6. the preparation method of the Zr-Cu-Ni-Al non-crystaline amorphous metal of interpolation trace B according to claim 5 is characterized in that: cool off with the rate of cooling greater than 100 ℃/second after the said mother alloy sample melted.

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