阅读说明：本技术 一种低弹性模量锆合金及其制备方法和应用 (Low-elasticity-modulus zirconium alloy and preparation method and application thereof ) 是由 刘日平 姬朋飞 李波 陈博涵 逯昊燃 石鹤洋 马明臻 张新宇 于 2021-08-11 设计创作，主要内容包括：本发明属于合金技术领域,特别涉及一种低弹性模量锆合金及其制备方法和应用。本发明提供的低弹性模量锆合金,以质量百分含量计,包括以下元素：Nb0.5～15％、Sn0.5～5％、Hf0.1～4.5％和余量的Zr。在本发明中,Nb具有固溶强化的作用,能够显著提高锆合金的强度,能够控制锆合金中β相的含量,从而降低锆合金的弹性模量；本发明通过严格控制各元素的含量,利用合金化,使Nb与Zr形成固溶体,实现固溶强化；Sn和Hf属于中性元素,在α相和β相中固溶强化作用明显,通过各元素协同配合,共同在保证锆合金强度的基础上降低锆合金的弹性模量。而且,本申请中Nb含量低,有利于降低锆合金的成本。(The invention belongs to the technical field of alloys, and particularly relates to a low-elasticity-modulus zirconium alloy and a preparation method and application thereof. The low-elasticity-modulus zirconium alloy provided by the invention comprises the following elements in percentage by mass: nb0.5-15%, Sn0.5-5%, Hf0.1-4.5% and the balance Zr. In the invention, Nb has the function of solid solution strengthening, the strength of the zirconium alloy can be obviously improved, and the content of beta phase in the zirconium alloy can be controlled, so that the elastic modulus of the zirconium alloy is reduced; according to the invention, the content of each element is strictly controlled, and Nb and Zr form a solid solution by alloying, so that solid solution strengthening is realized; sn and Hf belong to neutral elements, the solid solution strengthening effect is obvious in alpha phase and beta phase, and the elastic modulus of the zirconium alloy is reduced on the basis of ensuring the strength of the zirconium alloy through the synergistic cooperation of the elements. Moreover, the Nb content is low, and the cost of the zirconium alloy is reduced.)

1. A low elastic modulus zirconium alloy comprises the following elements in percentage by mass:

0.5 to 15% of Nb, 0.5 to 5% of Sn, 0.1 to 4.5% of Hf, and the balance of Zr.

2. The low elastic modulus zirconium alloy of claim 1, wherein the low elastic modulus zirconium alloy has a structure comprising lath alpha phase and/or equiaxed beta phase.

3. The low elastic modulus zirconium alloy according to claim 2, wherein the lath width of the lath α phase is 1 to 7.2 μm; the crystal grain size of the equiaxed beta phase is 52-240 mu m.

4. The low elastic modulus zirconium alloy according to any one of claims 1 to 3, wherein the low elastic modulus zirconium alloy has an elastic modulus of 45 to 80GPa, a yield strength of 350 to 600MPa, a tensile strength of 600 to 800MPa, and an elongation of 12 to 26%.

5. A method for preparing the low elastic modulus zirconium alloy of any one of claims 1 to 4, comprising the steps of:

providing an alloy ingot, wherein the chemical composition of the ingot is consistent with that of the low-elasticity-modulus zirconium alloy;

and annealing the alloy ingot to obtain the low-elasticity-modulus zirconium alloy.

6. The method according to claim 5, wherein the method for preparing the alloy ingot comprises: sequentially smelting and cooling alloy raw materials to obtain the alloy ingot;

the smelting temperature is 2300-2600 ℃.

7. The preparation method according to claim 5, wherein the annealing temperature is 450-600 ℃, and the holding time is 1-2 h.

8. The method of claim 5 or 7, wherein the annealing is performed under a protective gas.

9. Use of the low elastic modulus zirconium alloy of any one of claims 1 to 4 or the low elastic modulus zirconium alloy prepared by the preparation method of any one of claims 5 to 8 in the preparation of force-bearing implant materials.

Technical Field

The invention belongs to the technical field of alloys, and particularly relates to a low-elasticity-modulus zirconium alloy and a preparation method and application thereof.

Background

Zirconium has excellent biocompatibility and is widely applied to the field of biomedical science. However, the zirconium alloy in the biomedical field still has many problems, such as low strength and high elastic modulus. For example, the Zr-Nb system in the zirconium alloy system is a typical alloy system, and the yield strength of the Zr-Nb system alloy in the prior art is usually only about 400MPa, and the strength is low, and the elastic modulus of the zirconium alloy is high. For example, Chinese patent application CN110408815A discloses an AM decomposition type Zr-Nb-Ti alloy material with low elastic modulus and biomedical low elastic modulus and a preparation method thereof, but the niobium content in the alloy is 15-45%, and the cost of the raw material is high.

Disclosure of Invention

In view of the above, the present invention provides a low elastic modulus zirconium alloy and a preparation method thereof, and the low elastic modulus zirconium alloy provided by the present invention has the characteristics of low elastic modulus, high strength, excellent plasticity and low cost.

In order to achieve the purpose of the invention, the invention provides the following technical scheme:

the invention provides a low-elasticity-modulus zirconium alloy which comprises the following elements in percentage by mass:

0.5 to 15% of Nb, 0.5 to 5% of Sn, 0.1 to 4.5% of Hf, and the balance of Zr.

Preferably, the low elastic modulus zirconium alloy has a structure comprising lath alpha phase and/or equiaxed beta phase.

Preferably, the width of the lath alpha phase is 1-7.2 μm; the crystal grain size of the equiaxed beta phase is 52-240 mu m.

Preferably, the elastic modulus of the low-elastic-modulus zirconium alloy is 45-80 GPa, the yield strength is 350-600 MPa, the tensile strength is 600-800 MPa, and the elongation is 12-26%.

The invention also provides a preparation method of the low-elasticity-modulus zirconium alloy, which comprises the following steps:

providing an alloy ingot, wherein the chemical composition of the ingot is consistent with that of the low-elasticity-modulus zirconium alloy;

and annealing the alloy ingot to obtain the low-elasticity-modulus zirconium alloy.

Preferably, the preparation method of the alloy ingot comprises the following steps: sequentially smelting and cooling alloy raw materials to obtain the alloy ingot;

the smelting temperature is 2300-2600 ℃.

Preferably, the annealing temperature is 450-600 ℃, and the heat preservation time is 1-2 h.

Preferably, the annealing is performed under a protective gas condition.

The invention also provides application of the low-elasticity-modulus zirconium alloy in the technical scheme or the low-elasticity-modulus zirconium alloy prepared by the preparation method in the technical scheme in preparation of a bearing implant material.

The invention provides a low-elasticity-modulus zirconium alloy which comprises the following elements in percentage by mass: 0.5 to 15% of Nb, 0.5 to 5% of Sn, 0.1 to 4.5% of Hf, and the balance of Zr. In the invention, Nb and Zr belong to the same main group, have the effect of solid solution strengthening, can obviously improve the strength of the zirconium alloy, and simultaneously, the addition of Nb is controlled, so that the improvement of the content of beta phase in the zirconium alloy is facilitated, the elastic modulus of the zirconium alloy is reduced, and the corrosion resistance, the plasticity and the biocompatibility of the zirconium alloy are improved; sn belongs to neutral elements, has obvious solid solution strengthening effect in an alpha phase and a beta phase, improves the strength of the alloy, and simultaneously has good biocompatibility, thereby ensuring the biocompatibility of the zirconium alloy; hf belongs to neutral elements, has obvious solid solution strengthening effect in an alpha phase and a beta phase, and is favorable for improving the strength of the zirconium alloy. According to the invention, the content of each element is strictly controlled, and Nb and Zr form a solid solution by alloying, so that solid solution strengthening is realized; sn and Hf belong to neutral elements, the solid solution strengthening effect is obvious in alpha phase and beta phase, and the elastic modulus of the zirconium alloy is reduced on the basis of ensuring the strength of the zirconium alloy through the synergistic cooperation of the elements. Moreover, the Nb content is low, and the cost of the zirconium alloy is reduced.

The test result of the embodiment shows that the low-elasticity-modulus zirconium alloy provided by the invention has the elasticity modulus of 52-76 GPa, the yield strength of 421.8-591.2 MPa, the tensile strength of 642.3-772.6 MPa, the elongation of 15.2-20.3%, and has low elasticity modulus on the basis of high strength and high plasticity.

The invention also provides a preparation method of the low-elasticity-modulus zirconium alloy, which comprises the following steps: providing an alloy ingot, wherein the chemical composition of the ingot is consistent with that of the low-elasticity-modulus zirconium alloy; and annealing the alloy ingot to obtain the low-elasticity-modulus zirconium alloy. According to the invention, through annealing, the residual stress formed in the smelting process can be eliminated, and partial microscopic defects can be eliminated, so that the alloy components are further homogenized; the invention can obtain the zirconium alloy with excellent comprehensive performance only by annealing after smelting, and the method is simple and easy to implement.

Drawings

FIG. 1 is a metallographic optical micrograph of a low elastic modulus zirconium alloy obtained in example 1;

FIG. 2 is a metallographic optical micrograph of a low elastic modulus zirconium alloy obtained in example 2;

FIG. 3 is a metallographic optical micrograph of a low elastic modulus zirconium alloy obtained in example 3;

FIG. 4 is a metallographic optical micrograph of a low elastic modulus zirconium alloy obtained in example 4;

FIG. 5 is a metallographic optical micrograph of the zirconium alloy obtained in comparative example 1.

Detailed Description

The invention provides a low-elasticity-modulus zirconium alloy which comprises the following elements in percentage by mass:

0.5 to 15% of Nb, 0.5 to 5% of Sn, 0.1 to 4.5% of Hf, and the balance of Zr.

In the invention, the low-elastic-modulus zirconium alloy comprises 0.5-15% of Nb by mass percentage, preferably 1.5-14%, more preferably 2-13%, and still more preferably 2.5-12%. In the invention, Nb and Zr belong to the same main group, have the function of solid solution strengthening and can improve the strength of the zirconium alloy; meanwhile, the content of beta phase in the alloy can be controlled by controlling the addition of Nb, so that the elastic modulus of the zirconium alloy is reduced, and the corrosion resistance, the plasticity and the biocompatibility of the zirconium alloy are improved.

In the invention, the low-elastic-modulus zirconium alloy comprises, by mass, 0.5% -5% of Sn, preferably 0.8-4.5%, more preferably 0.9-4.3%, and still more preferably 1-4%. In the invention, Sn belongs to neutral elements, has obvious solid solution strengthening effect in an alpha phase and a beta phase, and is beneficial to improving the strength of the zirconium alloy; meanwhile, Sn has good biocompatibility, and is beneficial to improving the biocompatibility of the zirconium alloy.

In the invention, the low-elastic-modulus zirconium alloy comprises 0.1-4.5% of Hf (hafnium), preferably 0.5-4.2%, more preferably 1-4%, and even more preferably 1.6-3.6% in percentage by mass. In the invention, Hf belongs to neutral elements, has obvious solid solution strengthening effect in alpha phase and beta phase, and is beneficial to improving the strength of the zirconium alloy.

In the invention, the low-elastic-modulus zirconium alloy comprises Zr in the balance by mass percentage. In the present invention, Zr is a base element of the zirconium alloy.

In the present invention, the structure of the low elastic modulus zirconium alloy preferably includes lath alpha phase and/or equiaxed beta phase. In the present invention, when the structure of the low elastic modulus zirconium alloy includes both the lath α phase and the equiaxed β phase, the structure of the low elastic modulus zirconium alloy is a basket structure formed by the lath α phase and the equiaxed β phase.

In the invention, the lath width of the lath alpha phase is preferably 1-7.2 μm, more preferably 1.5-7 μm, and still more preferably 2-6.5 μm. In the invention, the crystal grain size of the equiaxed beta phase is preferably 52-240 μm, more preferably 55-235 μm, and still more preferably 57-232 μm.

In the invention, the crystal structure of the alpha phase is a close-packed hexagonal structure and has the characteristic of high strength; the beta phase is a body-centered cubic structure, is easy to coordinate and deform, and is easy to obtain low elastic modulus, but the strength is low, the higher the Nb content is, the larger the beta phase proportion of the corresponding component is, so that the relative content of the alpha phase and the beta phase in the alloy is regulated and controlled by controlling the Nb content, and the zirconium alloy with excellent comprehensive mechanical properties is favorably obtained.

In the invention, as Nb and Sn elements in the zirconium alloy increase, the beta transformation temperature of the alloy decreases, and under similar cooling conditions, the nucleation number of original beta crystal grains increases, the size of the generated original beta crystal grains is smaller, and the content of beta phase is higher.

The low-elasticity-modulus zirconium alloy provided by the invention has good biocompatibility and has application potential as a force-bearing implant material.

In the invention, the elastic modulus of the low-elastic-modulus zirconium alloy is preferably 45-80 GPa, the yield strength is preferably 350-600 MPa, the tensile strength is preferably 600-800 MPa, and the elongation is preferably 12-26%.

The invention also provides a preparation method of the low-elasticity-modulus zirconium alloy, which comprises the following steps:

providing an alloy ingot, wherein the chemical composition of the ingot is consistent with that of the low-elasticity-modulus zirconium alloy;

and annealing the alloy ingot to obtain the low-elasticity-modulus zirconium alloy.

The invention provides an alloy ingot, the chemical composition of which is consistent with that of a low-elastic-modulus zirconium alloy.

In the present invention, the method for producing an alloy ingot preferably includes: and smelting and cooling the alloy raw materials in sequence to obtain the alloy ingot.

In the invention, the alloy raw materials are preferably sponge zirconium, pure niobium wires and pure tin particles; the sponge zirconium contains hafnium. The invention adopts hafnium-containing zirconium sponge, i.e. the zirconium sponge does not need to be purified. The invention adopts zirconium sponge without zirconium and hafnium separation, which is beneficial to reducing the cost of raw materials. In the invention, the purity of the pure niobium wire is preferably more than or equal to 99.9%. In the present invention, the purity of the pure tin particles is preferably not less than 99.9%. The specific source and the addition amount of the alloy raw materials are not specially limited, so that the zirconium alloy with low elastic modulus meeting the chemical composition requirement is obtained. Specifically, the amount of each raw material alloy is adjusted appropriately according to the composition of the alloy raw material actually obtained, so that a low-elastic-modulus zirconium alloy satisfying the chemical composition can be obtained.

According to the invention, the alloy raw materials are preferably cleaned and dried in sequence and then used for smelting. In the present invention, the cleaning is preferably ultrasonic cleaning. In the present invention, the cleaning agent in the ultrasonic cleaning is preferably absolute ethyl alcohol. The ultrasonic cleaning is not particularly limited in the present invention, and may be ultrasonic cleaning known to those skilled in the art. The washing and drying are not particularly limited in the present invention, and washing and drying known to those skilled in the art may be employed. The invention removes impurities and oil stains on the surface of the alloy raw material by cleaning.

In the present invention, the melting is preferably vacuum arc melting, and more preferably non-consumable vacuum arc melting. In the present invention, the melting facility is preferably a non-consumable arc melting furnace, more preferably a non-consumable vacuum arc melting furnace. In the present invention, the crucible in the non-consumable vacuum arc melting furnace is preferably a water-cooled copper crucible. According to the invention, after the equipment cavity for smelting is vacuumized, the protective gas is filled into the vacuumized equipment cavity for smelting, and then smelting is carried out. In the invention, the vacuum degree in the equipment cavity for smelting after vacuum pumping is preferably less than or equal to 8 multiplied by 10^-3Pa, more preferably 3X 10^-3Pa～7×10^-3Pa. In the present invention, the shielding gas is preferably argon gas. The filling amount of the argon is not specially limited so as to meet the consumption of the ionized gas for arc melting. The invention adopts the mode of firstly vacuumizing and then introducing argon, can avoid a large amount of oxygen absorption and nitrogen absorption of Zr under the condition of high temperature, and can also provide ionized gas for vacuum arc melting.

In the invention, the smelting temperature is 2300-2600 ℃, preferably 2330-2580 ℃, and more preferably 2350-2550 ℃. In the invention, the current of non-consumable arc melting in the melting is preferably 480-450A, and more preferably 400-430A. In the present invention, the smelting is preferably carried out under a protective gas condition. In the present invention, the shielding gas is preferably argon gas. In the invention, the pressure of the protective gas is preferably 0.04-0.05 MPa, and more preferably 0.042-0.048 MPa.

According to the invention, the casting blank is cooled after each non-consumable vacuum arc melting is finished, and the obtained casting blank is turned over for next non-consumable vacuum arc melting. In the invention, the time of each non-consumable vacuum arc melting is preferably 3-5 min independently, and more preferably 3.5-4.5 min independently. In the invention, the non-consumable arc melting times in the melting are preferably not less than 5 times, and more preferably 6-10 times. The invention preferably repeatedly carries out non-consumable vacuum arc melting, which is beneficial to ensuring that the components of the obtained alloy cast ingot are more uniform.

In the invention, during smelting, the smelting liquid firstly forms a beta phase in the solidification process, and the beta phase is completely or partially converted into an alpha phase along with the reduction of the temperature.

After the alloy ingot is obtained, annealing the alloy ingot to obtain the low-elastic-modulus zirconium alloy.

Before annealing, the present invention preferably further comprises: grinding and polishing the surface of the alloy cast ingot; the present invention is not particularly limited to the above-described lapping and polishing, and the lapping known to those skilled in the art may be used. The method is beneficial to improving the surface smoothness of the alloy cast ingot and the uniform heating of the alloy cast ingot during annealing and has strong repeatability through grinding and polishing.

According to the invention, the alloy ingot is preferably cut to obtain an alloy ingot sheet; the thickness of the alloy cast ingot thin plate is preferably 5-6 mm. In the invention, the alloy ingot sheet is annealed, which is more beneficial to uniform annealing.

In the invention, the annealing temperature is preferably 450-600 ℃, and more preferably 470-580 ℃; the heat preservation time is preferably 1-2 h, and more preferably 1.2-1.8 h. In the present invention, the temperature of the annealing is preferably obtained by raising the temperature to room temperature; the heating rate is preferably 10-20 ℃/min, and more preferably 10-15 ℃/min. The present invention preferably cools the annealed alloy billet to room temperature. In the present invention, the cooling after the annealing is preferably furnace cooling. In the present invention, the annealing is preferably performed under a protective gas condition; in the present invention, the shielding gas is preferably argon gas. In the present invention, the annealing apparatus is preferably a vacuum tube furnace. In an embodiment of the present invention, the vacuum tube furnace is preferably SK-G06143 available from Zhonghuan laboratory electric furnace Co., Ltd. The invention is beneficial to effectively eliminating residual stress formed in the smelting process and partial microscopic defects through annealing, so that the components of the zirconium alloy are further homogenized.

The invention can obtain the zirconium alloy with excellent comprehensive performance only by simple annealing after smelting, and the method is simple and easy to implement.

After annealing, the present invention preferably further comprises: and sequentially polishing the surfaces of the zirconium alloys obtained by annealing. The present invention is not particularly limited to the polishing, and polishing known to those skilled in the art may be used. In the invention, the oxide skin on the surface of the zirconium alloy is removed by polishing.

The preparation method of the low-elasticity-modulus zirconium alloy provided by the invention is low in cost and simple and feasible.

The invention also provides application of the low-elasticity-modulus zirconium alloy in the technical scheme or the low-elasticity-modulus zirconium alloy prepared by the preparation method in the technical scheme in preparation of a bearing implant material.

The invention is not particularly limited in this application, and can be applied to bearing implant materials well known to those skilled in the art.

In order to further illustrate the present invention, the following examples are provided to describe the low elastic modulus zirconium alloy of the present invention and its preparation method and application in detail, but they should not be construed as limiting the scope of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

Designing the chemical components of the low-elasticity-modulus zirconium alloy as Zr-0.6Nb-0.5Sn-4.4Hf, namely Nb 0.6%, Sn 0.5%, Hf 4.4%, and the balance of Zr and inevitable impurities in percentage by mass;

placing the alloy raw material into absolute ethyl alcohol to make ultrasonic cleaning, air-drying, mixing, placing into water-cooled copper crucible, placing into non-consumable vacuum electric arc melting furnace, vacuumizing the furnace cavity to 5X 10^-3Pa, then filling argon, and the vacuum degree is 5X 10^-3Carrying out non-consumable arc melting under the argon condition with Pa and the pressure of 0.04-0.05 MPa, wherein the melting temperature is 2400 ℃, the current is 420A in the melting process, the single melting time is 4min, cooling is carried out after melting, the obtained casting blank is turned over, the next non-consumable arc melting treatment is carried out, 6 times of non-consumable arc melting are carried out in total, and an alloy ingot is obtained after cooling;

cutting the obtained alloy ingot to obtain an alloy ingot sheet with the thickness of 5mm, polishing the surface of the alloy ingot sheet, placing the alloy ingot sheet in a vacuum tube furnace, heating the alloy ingot sheet to 500 ℃ at the speed of 10 ℃/min, preserving the temperature of the alloy ingot sheet at 500 ℃ for 100min, cooling the alloy ingot sheet to room temperature along with the furnace, taking out the alloy ingot sheet, polishing the alloy ingot sheet to remove oxide skin on the surface, cleaning and air-drying the alloy ingot sheet to obtain the low-elasticity-modulus zirconium alloy.

And performing component detection on the obtained low-elastic-modulus zirconium alloy by adopting an ICP-OES method, and determining that the chemical component of the obtained low-elastic-modulus zirconium alloy is Zr-0.57Nb-0.44Sn-4.4Hf, namely Nb 0.57%, Sn 0.44%, Hf 4.4%, and the balance Zr and inevitable impurities in percentage by mass.

The metallographic microstructure of the low-modulus zirconium alloy obtained in example 1 was measured, and the test chart is shown in FIG. 1. As can be seen from fig. 1, the low elastic modulus zirconium alloy prepared in this example is composed of a lath α phase having an average lath width of 6 μm.

Example 2

Designing the chemical components of the low-elasticity-modulus zirconium alloy as Zr-3Nb-1Sn-4.2Hf, namely Nb 3%, Sn 1%, Hf 4.2% by mass, and the balance of Zr and inevitable impurities;

placing the alloy raw material into absolute ethyl alcohol to make ultrasonic cleaning, air-drying, mixing, placing into water-cooled copper crucible, placing into non-consumable vacuum electric arc melting furnace, vacuumizing the furnace cavity to 5X 10^-3Pa, then filling argon, and the vacuum degree is 5X 10^-3Carrying out non-consumable arc melting under the argon condition with Pa and the pressure of 0.04-0.05 MPa, wherein the melting temperature is 2400 ℃, the current is 420A in the melting process, the single melting time is 4min, cooling is carried out after melting, the obtained casting blank is turned over, the next non-consumable arc melting treatment is carried out, 6 times of non-consumable arc melting are carried out in total, and an alloy ingot is obtained after cooling;

cutting the obtained alloy ingot to obtain an alloy ingot sheet with the thickness of 5mm, polishing the surface of the alloy ingot sheet, placing the alloy ingot sheet in a vacuum tube furnace, heating the alloy ingot sheet to 500 ℃ at the speed of 10 ℃/min, preserving the temperature of the alloy ingot sheet at 500 ℃ for 100min, cooling the alloy ingot sheet to room temperature along with the furnace, taking out the alloy ingot sheet, polishing the alloy ingot sheet to remove oxide skin on the surface, cleaning and air-drying the alloy ingot sheet to obtain the low-elasticity-modulus zirconium alloy.

And detecting the components of the obtained low-elastic-modulus zirconium alloy by adopting an ICP-OES method, and determining that the chemical component of the obtained low-elastic-modulus zirconium alloy is Zr-2.9Nb-0.9Sn-4.2Hf, namely Nb 2.9%, Sn 0.9%, Hf 4.2%, and the balance of Zr and inevitable impurities in percentage by mass.

The metallographic microstructure of the low-modulus zirconium alloy obtained in example 2 was measured, and the test chart is shown in FIG. 2. As can be seen from fig. 2, the low elastic modulus zirconium alloy prepared in this example is a typical α + β phase basket structure, in which the volume content of the equiaxed β phase is 5-15%, the equiaxed β phase is less distributed among the lath α phases, and the average lath width of the lath α phase is 4.5 μm.

Example 3

The chemical composition of the low-elasticity-modulus zirconium alloy is Zr-5Nb-2Sn-4.1Hf, namely Nb 5%, Sn 2%, Hf 4.1% by mass, and the balance of Zr and inevitable impurities;

placing the alloy raw material into absolute ethyl alcohol to make ultrasonic cleaning, air-drying, mixing, placing into water-cooled copper crucible, placing into non-consumable vacuum electric arc melting furnace, vacuumizing the furnace cavity to 5X 10^-3Pa, then filling argon, and the vacuum degree is 5X 10^-3Carrying out non-consumable arc melting under the argon condition with Pa and the pressure of 0.04-0.05 MPa, wherein the melting temperature is 2400 ℃, the current is 420A in the melting process, the single melting time is 4min, cooling is carried out after melting, the obtained casting blank is turned over, the next non-consumable arc melting treatment is carried out, 6 times of non-consumable arc melting are carried out in total, and an alloy ingot is obtained after cooling;

cutting the obtained alloy ingot to obtain an alloy ingot sheet with the thickness of 5mm, polishing the surface of the alloy ingot sheet, placing the alloy ingot sheet in a vacuum tube furnace, heating the alloy ingot sheet to 500 ℃ at the speed of 10 ℃/min, preserving the temperature of the alloy ingot sheet at 500 ℃ for 100min, cooling the alloy ingot sheet to room temperature along with the furnace, taking out the alloy ingot sheet, polishing the alloy ingot sheet to remove oxide skin on the surface, cleaning and air-drying the alloy ingot sheet to obtain the low-elasticity-modulus zirconium alloy.

And detecting the components of the obtained low-elastic-modulus zirconium alloy by adopting an ICP-OES method, and determining that the chemical component of the obtained low-elastic-modulus zirconium alloy is Zr-5.1Nb-1.8Sn-4.1Hf, namely Nb 5.1%, Sn 1.8%, Hf 4.1%, and the balance of Zr and inevitable impurities in percentage by mass.

The metallographic microstructure of the low-modulus zirconium alloy obtained in example 3 was measured, and the graph is shown in FIG. 3. As can be seen from fig. 3, the low-elastic-modulus zirconium alloy prepared in this example is a typical α + β phase structure, in which the volume content of the equiaxed β phase is 50-70%, the equiaxed β phase is more abundant and distributed among the lath α phases, and the average lath width of the lath α phase is 5.1 μm.

Example 4

The chemical components of the low-elasticity-modulus zirconium alloy are Zr-10Nb-2.5Sn-3.8Hf, namely Nb 10%, Sn 2.5%, Hf 3.8%, and the balance of Zr and inevitable impurities in percentage by mass;

placing the alloy raw material into absolute ethyl alcohol to make ultrasonic cleaning, air-drying, mixing, placing into water-cooled copper crucible, placing into non-consumable vacuum electric arc melting furnace, vacuumizing the furnace cavity to 5X 10^-3Pa, then filling argon, and the vacuum degree is 5X 10^-3Carrying out non-consumable arc melting under the argon condition with Pa and the pressure of 0.04-0.05 MPa, wherein the melting temperature is 2400 ℃, the current is 420A in the melting process, the single melting time is 4min, cooling is carried out after melting, the obtained casting blank is turned over, the next non-consumable arc melting treatment is carried out, 6 times of non-consumable arc melting are carried out in total, and an alloy ingot is obtained after cooling;

cutting the obtained alloy ingot to obtain an alloy ingot sheet with the thickness of 5mm, polishing the surface of the alloy ingot sheet, placing the alloy ingot sheet in a vacuum tube furnace, heating the alloy ingot sheet to 500 ℃ at the speed of 10 ℃/min, preserving the temperature of the alloy ingot sheet at 500 ℃ for 100min, cooling the alloy ingot sheet to room temperature along with the furnace, taking out the alloy ingot sheet, polishing the alloy ingot sheet to remove oxide skin on the surface, cleaning and air-drying the alloy ingot sheet to obtain the low-elasticity-modulus zirconium alloy.

And detecting the components of the obtained low-elastic-modulus zirconium alloy by adopting an ICP-OES method, and determining that the chemical component of the obtained low-elastic-modulus zirconium alloy is Zr-9.8Nb-2.3Sn-3.8Hf, namely Nb 9.8%, Sn 2.3%, Hf 3.8%, and the balance of Zr and inevitable impurities in percentage by mass.

The metallographic microstructure of the low-modulus zirconium alloy obtained in example 4 was measured, and the test pattern is shown in FIG. 4. As can be seen from fig. 4, the low elastic modulus zirconium alloy prepared in this example is a typical equiaxed beta phase structure, without the presence of lath alpha phase, and the equiaxed beta phase has an average grain size of 132 μm.

Comparative example 1

Designing the chemical components of the zirconium alloy as Zr-2.5Nb-4.4Hf, namely Nb 2.5 percent, Hf 4.4 percent, and the balance of Zr and inevitable impurities according to the mass percentage; the remaining technical means were the same as in example 1 to obtain a zirconium alloy.

And detecting the components of the obtained zirconium alloy by adopting an ICP-OES method, and determining that the chemical component of the obtained zirconium alloy is Zr-2.48Nb-4.4Hf, namely Nb 2.48 percent, Hf 4.4 percent, and the balance of Zr and inevitable impurities according to the mass percentage.

The metallographic microstructure of the zirconium alloy obtained in comparative example 1 was measured, and the graph is shown in FIG. 5. As can be seen from fig. 5, the zirconium alloy prepared in the present comparative example is a typical α + β phase basket structure in which the equiaxed β phase is 7 to 12% by volume, less distributed among lath α phases, and the lath α phases have an average lath width of 4.5 μm.

The zirconium alloys obtained in the examples 1-4 and the comparative example 1 are tested according to GB/T228-: cutting a bone-rod-shaped uniaxial tensile sample from the zirconium alloy plate by utilizing linear cutting, and testing the mechanical property of the uniaxial tensile sample according to the national standard GBT 228-2002; during the test, at least 5 tensile specimens were cut out of the samples of each example to ensure the reproducibility of the data, and the measurement was carried out using a room-temperature uniaxial tensile test with an Instron5982 Universal Material testing machine (manufacturer: Instron, USA) whose tensile displacement was monitored all the way with an extensometer, the tensile rate being set at 5X 10^-4s^-1And a tensile test was performed. The test results are shown in Table 1.

TABLE 1 Performance test results of zirconium alloys obtained in examples 1 to 4 and comparative example 1

As can be seen from Table 1, the low-elastic-modulus zirconium alloy provided by the invention has the elastic modulus of 52-76 GPa and low elastic modulus; the yield strength is 421.8-591.2 MPa, the tensile strength is 642.3-772.6 MPa, the elongation is 15.2-20.3%, and the steel has high yield strength, tensile strength and excellent plasticity.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.