1. A method for preparing a tantalum coating on the surface of a zirconium alloy is characterized by comprising the following steps:

carrying out chlorination reaction on chlorine and preheated metal tantalum to generate tantalum chloride gas, wherein the temperature of the chlorination reaction is 1000-1200 ℃;

and carrying out reduction reaction on the tantalum chloride gas and hydrogen on the surface of the preheated zirconium alloy to generate a tantalum coating on the surface of the zirconium alloy, wherein the temperature of the reduction reaction is 1000-1200 ℃.

2. The method of claim 1, wherein the tantalum coating has a thickness of 20 to 50 μm.

3. The method of claim 1, wherein the flow rate of the chlorine gas is 40 to 60 sccm.

4. The method according to claim 1 or 4, wherein the pressure of chlorine gas is 100 to 200Pa during the chlorination reaction.

5. The method of claim 1, wherein the hydrogen gas is flowed at a rate of 40 to 60sccm and the tantalum chloride is flowed at a rate of 16 to 24 sccm.

6. The method according to claim 1 or 5, wherein the pressure of hydrogen gas is 100 to 200MPa during the reduction reaction.

7. The method according to claim 1, wherein the time of the reduction reaction is 25 to 40 min.

8. The method according to claim 1, wherein the zirconium alloy is rotated at a speed of 5 to 10r/min during the reduction reaction.

9. The method of claim 1, wherein the chlorination reaction and the reduction reaction are performed in two separate reaction chambers;

the chlorination reaction is carried out in a first reaction chamber, the generated tantalum chloride gas is introduced into a second reaction chamber from the first reaction chamber to carry out the reduction reaction with hydrogen, and a zirconium alloy is arranged in the second reaction chamber.

10. The method of claim 1, wherein the zirconium alloy comprises a zirconium titanium niobium alloy, a zirconium titanium molybdenum alloy, or a zirconium niobium silicon alloy.

Background

Zirconium alloys have attracted scientific attention because of their excellent mechanical properties and corrosion resistance. In addition, the zirconium alloy also has larger elastic strain capacity, the elastic limit reaches 2 percent (the elastic limit of medical stainless steel is only 0.3 percent, and the elastic limit of natural bone is 1 percent), the elastic modulus is 70-100 GPa (the elastic modulus of titanium and Ti-6Al-4V alloy is about 110-125 GPa, and the elastic modulus of natural bone is about 20GPa), and the zirconium alloy material is closer to the performance of the natural bone of a human body than the conventional medical vanadium-containing titanium alloy material. In addition, the zirconium alloy has good abrasion resistance, corrosion resistance and fatigue resistance, and hardly generates abrasion debris. Therefore, the zirconium alloy has a wide application prospect in the aspects of artificial joints, tooth root implants, femoral head supports and the like.

However, the biocompatibility of zirconium alloy as medical alloy and the corrosion resistance in the environment of human body fluid need to be further improved.

Disclosure of Invention

In view of the above, the invention provides a method for preparing a tantalum coating on the surface of a zirconium alloy, the method provided by the invention has the advantages that metal tantalum is uniformly distributed on the surface of the zirconium alloy, the biocompatibility and the corrosion resistance of the zirconium alloy are favorably improved, meanwhile, the method provided by the invention has simple preparation conditions and low cost, and can be used for large-scale production.

In order to achieve the above object, the present invention provides the following technical solutions:

the invention provides a method for preparing a tantalum coating on the surface of a zirconium alloy, which comprises the following steps:

carrying out chlorination reaction on chlorine and preheated metal tantalum to generate tantalum chloride gas, wherein the temperature of the chlorination reaction is 1000-1200 ℃;

and carrying out reduction reaction on the tantalum chloride gas and hydrogen on the surface of the preheated zirconium alloy to generate a tantalum coating on the surface of the zirconium alloy, wherein the temperature of the reduction reaction is 1000-1200 ℃.

Preferably, the thickness of the tantalum coating is 20-50 μm.

Preferably, the flow rate of the chlorine gas is 40-60 sccm.

Preferably, the pressure of the chlorine gas during the chlorination reaction is 100-200 Pa.

Preferably, the flow rate of the hydrogen is 40-60 sccm, and the flow rate of the tantalum chloride is 16-24 sccm.

Preferably, the pressure of the hydrogen gas during the reduction reaction is 100 to 200 MPa.

Preferably, the time of the reduction reaction is 25-40 min.

Preferably, the zirconium alloy is rotated at a speed of 5 to 10r/min during the reduction reaction.

Preferably, the chlorination reaction and the reduction reaction are carried out in two separate reaction chambers;

the chlorination reaction is carried out in a first reaction chamber, the generated tantalum chloride gas is introduced into a second reaction chamber from the first reaction chamber to carry out the reduction reaction with hydrogen, and a zirconium alloy is arranged in the second reaction chamber.

Preferably, the zirconium alloy comprises a zirconium titanium niobium alloy, a zirconium titanium molybdenum alloy or a zirconium niobium silicon alloy.

The invention provides a method for preparing a tantalum coating on the surface of a zirconium alloy, which comprises the following steps: carrying out chlorination reaction on chlorine and preheated metal tantalum to generate tantalum chloride gas, wherein the temperature of the chlorination reaction is 1000-1200 ℃; and carrying out reduction reaction on the tantalum chloride gas and hydrogen on the surface of the preheated zirconium alloy to generate a tantalum coating on the surface of the zirconium alloy, wherein the temperature of the reduction reaction is 1000-1200 ℃. Firstly, carrying out chlorination reaction on chlorine gas and preheated metal tantalum at 1000-1200 ℃ to generate tantalum chloride gas, and then carrying out in-situ reduction reaction on the tantalum chloride gas and hydrogen at 1000-1200 ℃ on the surface of the preheated zirconium alloy to obtain a tantalum coating; the method provided by the invention can enable the metal tantalum to be uniformly distributed on the surface of the zirconium alloy, is favorable for improving the biocompatibility of the zirconium alloy and the corrosion resistance in a body fluid environment, and meanwhile, the method provided by the invention uses the metal tantalum as a raw material of a chemical reduction reaction, compared with the method using tantalum chloride to directly carry out the chemical reduction reaction, the price of the metal tantalum is lower, and the large-scale production can be realized.

Drawings

FIG. 1 is a schematic view of a chemical vapor deposition apparatus according to an embodiment of the present invention,

the device comprises a metal, a first chamber, an induction heating coil, a vacuum exhaust pipe, a rotary workpiece frame, a resistance heater, a first chamber, a second chamber, a chlorine pipeline, a hydrogen pipeline and an exhaust hole, wherein 1-metal tantalum, 2-the first chamber, 3-the induction heating coil, 4-the vacuum exhaust pipe, 5-the rotary workpiece frame, 6-zirconium alloy, 7-the resistance heater, 8-the second chamber, 9-the chlorine pipeline, 10-the hydrogen pipeline and 11-the exhaust hole;

FIG. 2 is an SEM photograph of a tantalum-containing coating on the surface of a zirconium alloy in accordance with example 1 of the present invention;

FIG. 3 is an SEM photograph of a tantalum-containing coating on the surface of a zirconium alloy in accordance with example 2 of the present invention;

FIG. 4 is an SEM photograph of a tantalum-containing coating on the surface of a zirconium alloy in accordance with example 3 of the present invention.

Detailed Description

The invention provides a method for preparing a tantalum coating on the surface of a zirconium alloy, which comprises the following steps:

carrying out chlorination reaction on chlorine and preheated metal tantalum to generate tantalum chloride gas, wherein the temperature of the chlorination reaction is 1000-1200 ℃;

and carrying out reduction reaction on the tantalum chloride gas and hydrogen on the surface of the preheated zirconium alloy to generate a tantalum coating on the surface of the zirconium alloy, wherein the temperature of the reduction reaction is 1000-1200 ℃.

In the present invention, the starting materials are all commercially available products well known to those skilled in the art unless otherwise specified.

The method comprises the step of carrying out chlorination reaction on chlorine and preheated metal tantalum to generate tantalum chloride gas, wherein the temperature of the chlorination reaction is 1000-1200 ℃.

In the present invention, the moisture content of the chlorine gas is preferably 1% or less, more preferably 0.5% or less. The chlorine gas having an unsatisfactory water content is preferably subjected to a pretreatment in the present invention, the pretreatment preferably includes a purification in the present invention, the purification preferably removes water from the chlorine gas, and the present invention does not require a specific implementation process of the purification. In an embodiment of the present invention, the purification is preferably performed by drying, and in the present invention, the water content of the purified chlorine gas is preferably less than or equal to 1%, and more preferably less than or equal to 0.5%.

In the invention, the flow rate of the chlorine gas is preferably 40-60 sccm, and more preferably 50 sccm.

In the present invention, the pressure of the chlorine gas during the chlorination reaction is preferably 100 to 200Pa, and more preferably 120 to 150 Pa.

In the invention, the temperature of the chlorination reaction is 1000-1200 ℃, and 1050-1100 ℃ is preferred.

In the present invention, the temperature of the preheated metallic tantalum is preferably the same as the temperature of the chlorination reaction, and will not be described herein.

In the present invention, the chlorination reaction is preferably performed in a separate reaction chamber (first reaction chamber), and in a specific embodiment of the present invention, the present invention preferably places the metallic tantalum in the first reaction chamber, and the chlorine gas is introduced into the first reaction chamber before the metallic tantalum is preheated; according to the invention, the first reaction chamber is preferably vacuumized before chlorine gas is introduced, and the pressure of the first reaction chamber after vacuumization is preferably 1-5 Pa.

In the specific embodiment of the invention, when the pressure of the chlorine gas is preferably 100-200, the metal tantalum is preferably preheated, and the chlorine gas and the preheated metal tantalum are subjected to chlorination reaction to generate tantalum chloride gas.

After the tantalum chloride gas is generated, the tantalum chloride gas and hydrogen are subjected to reduction reaction on the surface of a preheated zirconium alloy, a tantalum coating is generated on the surface of the zirconium alloy, and the temperature of the reduction reaction is 1000-1200 ℃.

In the invention, the zirconium alloy is preferably a medical zirconium alloy, and particularly preferably comprises zirconium titanium niobiumAn alloy, a zirconium niobium alloy, a zirconium titanium molybdenum alloy or a zirconium niobium silicon alloy, in a particular embodiment of the invention, the zirconium titanium niobium alloy is preferably ZrTi₃₀Nb₁The zirconium niobium alloy is preferably Zr_2.5Nb。

In the present invention, the zirconium alloy is preferably subjected to a pretreatment, and in the present invention, the pretreatment preferably includes: the polishing, the decontamination, the cleaning and the drying are carried out in sequence, and the invention has no special requirements on the specific implementation process of the polishing and the decontamination; the method preferably removes an oxide layer on the surface of the zirconium alloy through polishing and decontamination, wherein the cleaning preferably comprises organic solvent cleaning and water cleaning in sequence, the organic solvent used in the organic solvent cleaning is preferably acetone, isopropanol or ethanol, more preferably acetone or ethanol, in the invention, the number of times of the organic solvent cleaning is preferably 1-3, the number of times of the water cleaning is preferably 1-3, and the oil stain on the surface of the zirconium alloy is removed through the organic solvent cleaning; the organic solvent used in the cleaning of the organic solvent is removed by water washing; the present invention has no special requirement on the specific implementation process of the drying, and a zirconium alloy drying method well known to those skilled in the art can be adopted, and the present invention preferably dries the zirconium alloy to a constant weight.

In the invention, the flow rate of the hydrogen is preferably 40-60 sccm, and more preferably 50 sccm; the flow rate of the tantalum chloride is preferably 16-24 sccm, and more preferably 20 sccm.

In the present invention, the tantalum chloride gas generated by the chlorination reaction is preferably introduced into the reaction chamber of the reduction reaction from the reaction chamber of the chlorination reaction.

In the present invention, the pressure of the hydrogen gas during the reduction reaction is preferably 100 to 200Pa, and more preferably 120 to 150 Pa.

In the present invention, the time of the reduction reaction is preferably 25 to 40min, and more preferably 30 min.

In the invention, the temperature of the reduction reaction is 1000-1200 ℃, and 1050-1100 ℃ is preferred.

In the present invention, the preheating temperature of the preheated zirconium alloy is preferably the same as the temperature of the reduction reaction, and will not be described herein again.

In the present invention, in the reduction reaction, the zirconium alloy is preferably rotated at a speed of preferably 5 to 10r/min, more preferably 6 to 8 r/min.

According to the invention, the zirconium alloy is rotated during the reduction reaction, so that the tantalum coating on the surface of the zirconium alloy is more uniform.

In the present invention, the reduction reaction is preferably carried out in a reaction chamber (second reaction chamber) different from the chlorination reaction; in the present invention, it is preferable that the zirconium alloy is placed in the second reaction chamber, and then the tantalum chloride gas and the hydrogen gas are introduced into the second reaction chamber, and in the present invention, the zirconium metal is preferably sizedThe height is 10 mm; before the tantalum chloride and the hydrogen are introduced, the second reaction chamber is preferably vacuumized, and after the vacuumization is finished, the pressure of the second reaction chamber is preferably 1-5 Pa.

Preferably, hydrogen is firstly introduced into the second reaction chamber, when the pressure of the hydrogen is preferably 100-200 Pa, and the zirconium alloy is preheated to the temperature of the reduction reaction, the tantalum chloride gas is introduced into the second reaction chamber from the first reaction chamber to carry out the reduction reaction with the hydrogen, the zirconium alloy is arranged in the second reaction chamber, and a tantalum coating is generated on the surface of the zirconium alloy.

In the invention, the thickness of the metal tantalum coating is preferably 20-50 μm, and more preferably 25-45 μm.

The method for preparing the tantalum coating on the surface of the zirconium alloy is preferably carried out in a chemical vapor deposition device, and in the specific implementation of the invention, the chemical vapor deposition device is preferably a high-temperature chemical vapor deposition device of a KJ-T1500CVD-DZ model, as shown in FIG. 1.

In the practice of the present invention, the chemical vapor reduction reaction apparatus (shown in FIG. 1) includes a second chamber 8;

a hydrogen pipeline 10 arranged at the top of the second chamber 8 and communicated with the second chamber 8, wherein the hydrogen pipeline 10 is used for introducing hydrogen, and a flow control meter is arranged on the hydrogen pipeline 10 and used for controlling the flow of the hydrogen;

a chlorine gas pipeline 9 penetrating through the top of the second chamber 8 and communicated with the first chamber 2, wherein the chlorine gas pipeline 9 is used for introducing chlorine gas, and a flow control meter is arranged on the chlorine gas pipeline 9 and is used for controlling the flow of the chlorine gas; the chlorine pipeline 10 is communicated with a first chamber 2 arranged in the second chamber, and metal tantalum 1 is placed in the first chamber 2;

in the present invention, the first chamber 2 is located inside the second chamber 8 while being located right above the rotating work rest 5.

In the invention, the outer surface of the first chamber 2 is provided with a resistance heater 7, and the resistance heater 7 is used for heating the metal tantalum 1 in the first chamber 2; the resistance heater 7 is provided with a thermocouple, the thermocouple is used for measuring the temperature of the metal tantalum 1, and the thermocouple is preferably a platinum-rhodium thermocouple;

the bottom of the first chamber 2 is provided with an exhaust hole 11, and the exhaust hole 11 is used for exhausting tantalum chloride gas generated by chlorination reaction from the first chamber 2 to the second chamber 8;

a rotary workpiece holder 5 is arranged at the bottom of the second chamber 8, and the rotary workpiece holder 5 is used for placing the zirconium alloy 6;

an induction heating coil 3 is arranged on the outer surface of the second chamber 8, the induction heating coil 3 is used for heating the zirconium alloy 6, the induction heating coil 3 is preferably a silicon controlled induction heating coil, and the induction heating coil 3 is provided with an optical pyrometer which is used for measuring the temperature of the zirconium metal 6; and a vacuum exhaust pipe 4 is arranged on the side wall of the second chamber 8, and the vacuum exhaust pipe 4 is used for vacuumizing the first chamber 2 and the second chamber 8.

According to the method provided by the invention, the chlorination reaction of the metal tantalum and the reduction reaction of the tantalum chloride are respectively carried out in two independent reaction chambers, so that the reaction efficiency is improved.

In the specific embodiment of the invention, when the tantalum coating is prepared on the surface of the zirconium alloy in the chemical vapor deposition device, firstly, the chromium alloy 6 is placed on the rotating workpiece 5, and the metal tantalum 1 is placed at the bottom of the first chamber 2; vacuumizing the second chamber 8 and the first chamber 2 through the vacuum exhaust pipe 4, when the vacuum degrees of the second chamber 8 and the first chamber 2 are pumped to 1-5 Pa, introducing hydrogen into the second chamber 8 through a hydrogen pipeline 10 until the pressure of the hydrogen is 100-200 Pa, and introducing chlorine into the back of the first chamber 2 through a chlorine pipeline until the pressure of the chlorine is 100-200 Pa; when the surface that adopts first cavity 2 sets up resistance heater 7 and heats metal tantalum 1 to chlorination's temperature, metal tantalum 1 and chlorine take place chlorination, generate tantalum chloride gas, and when the surface that adopts second cavity 8 set up induction heating coil 3 and heat zirconium alloy 6 to reduction's temperature, open the exhaust hole 11 of first cavity 2 bottom, discharge tantalum chloride gas to second cavity 8 in, tantalum chloride gas and hydrogen carry out reduction on the zirconium alloy surface generates the tantalum coating.

The technical solution of the present invention will be clearly and completely described below with reference to the embodiments 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

Adopting the chemical vapor deposition device shown in FIG. 1 to obtain ZrTi₃₀Nb₁Zirconium alloy (A), (B), (C), (Height 10mm) was placed in a chemical vapor deposition apparatus. Vacuumizing until the pressure is 5Pa, introducing chlorine into the first chamber, introducing hydrogen into the second chamber, adjusting the flow rate of the hydrogen to be 50sccm and the flow rate of the chlorine to be 50sccm, and then adjusting a vacuum device to ensure that the chlorine in the first chamber is in a vacuum stateThe pressure of the gas and the pressure of the hydrogen in the second chamber are 150Pa, the metal raw material tantalum sheet is heated to 1000 ℃ under the condition of the pressure of 150Pa, the purified chlorine gas is introduced into the first chamber of the metal tantalum sheet heated to 1000 ℃, and the chlorine gas and the metal tantalum react in the first chamber to generate TaCl₅Gaseous TaCl₅Is conveyed to the surface of a zirconium alloy matrix which is inductively heated to 1000 ℃, and is subjected to reduction reaction with hydrogen to deposit tantalum metal, wherein the rotation speed of the zirconium alloy matrix is controlled to be 5r/min, and the reduction reaction time is controlled to be 30 min. Waste gas generated by the reaction enters a mechanical pump discharge system after being trapped and dedusted by a filter flask.

Example 2

Adopting the chemical vapor deposition device shown in FIG. 1 to obtain ZrTi₃₀Nb₁Zirconium alloy (A), (B), (C), (B), (C), (B), (C)Height 10mm) was placed in a chemical vapor deposition apparatus. Vacuumizing to the pressure of 5Pa, introducing chlorine into the first chamber, introducing hydrogen into the second chamber, adjusting the flow rate of the hydrogen to 50sccm and the flow rate of the chlorine to 50sccm, then adjusting a vacuum device to ensure that the pressure of the chlorine in the first chamber and the pressure of the hydrogen in the second chamber are 150Pa, heating the metal raw material tantalum sheet to 1100 ℃ under the condition of the pressure of 150Pa, introducing the purified chlorine into the first chamber of the metal tantalum sheet heated to 1100 ℃, and reacting the chlorine and the metal tantalum in the first chamber to generate TaCl₅Gaseous TaCl₅Is conveyed to the surface of a zirconium alloy matrix which is inductively heated to 1000 ℃, and is subjected to reduction reaction with hydrogen to deposit tantalum metal, wherein the rotation speed of the zirconium alloy matrix is controlled to be 5r/min, and the reduction reaction time is controlled to be 30 min. Waste gas generated by the reaction enters a mechanical pump discharge system after being trapped and dedusted by a filter flask.

Example 3

Adopting the chemical vapor deposition device shown in FIG. 1 to obtain ZrTi₃₀Nb₁Zirconium alloy (A), (B), (C), (B), (C), (B), (C)Height 10mm) was placed in a chemical vapor deposition apparatus. Vacuumizing to the pressure of 5Pa, introducing chlorine into the first chamber, introducing hydrogen into the second chamber, adjusting the flow rate of the hydrogen to 50sccm and the flow rate of the chlorine to 50sccm, then adjusting a vacuum device to ensure that the pressure of the chlorine in the first chamber and the pressure of the hydrogen in the second chamber are 150Pa, heating the metal raw material tantalum sheet to 1200 ℃ under the condition of the pressure of 150Pa, introducing the purified chlorine into the first chamber of the metal tantalum sheet heated to 1200 ℃, and reacting the chlorine and the metal tantalum in the first chamber to generate TaCl₅Gaseous TaCl₅Is conveyed to the surface of a zirconium alloy matrix which is inductively heated to 1000 ℃, and is subjected to reduction reaction with hydrogen to deposit tantalum metal, wherein the rotation speed of the zirconium alloy matrix is controlled to be 5r/min, and the reduction reaction time is controlled to be 30 min. Waste gas generated by the reaction enters a mechanical pump discharge system after being trapped and dedusted by a filter flask.

Test example

Fig. 2 to 4 are electron micrographs of the tantalum coating on the surface of the zirconium alloy prepared in examples 1 to 3, and it can be seen from fig. 2 to 4 that the metal tantalum coating is prepared on the surface of the zirconium alloy by the preparation method provided by the present invention, wherein the thickness of the metal tantalum coating on the surface of the zirconium alloy is 25 μm.

Performing electrochemical corrosion point location test on the zirconium alloy with the tantalum coating on the surface prepared in the embodiment 1-3 in the artificial body fluid, wherein the artificial body fluid comprises the following components in percentage by mass: sodium chloride (NaCl, 87%), sodium bicarbonate (NaHCO)₃3.8 percent), potassium chloride (KCl, 2.44 percent), dipotassium phosphate trihydrate (K)₂HPO₄·3H₂O, 2.49%,), magnesium chloride hexahydrate (MgCl)₂·6H₂O, 2.32%), sodium sulfate (Na)₂SO₄0.77%), trimethylol amine alkane ((HOCH)₂)₃CNH₂1.03%), and finally the pH of the artificial body fluid is adjusted to 7.3 by hydrochloric acid; as shown in Table 1, it can be seen from Table 1 that the method provided in examples 1 to 3 produces a tantalum coating on the surface of a calcium alloy, and compared to a zirconium alloy without a tantalum coating, the corrosion potential, current density and corrosion rate thereof are higherAre all significantly reduced.

TABLE 1 results of electrochemical corrosion treatment of examples 1-3 and zirconium alloys not protected by a metallic tantalum coating

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.