CN103526174A - Surface modification method for delaying degradation rate of biomedical magnesium alloy - Google Patents
Surface modification method for delaying degradation rate of biomedical magnesium alloy Download PDFInfo
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- CN103526174A CN103526174A CN201310447446.4A CN201310447446A CN103526174A CN 103526174 A CN103526174 A CN 103526174A CN 201310447446 A CN201310447446 A CN 201310447446A CN 103526174 A CN103526174 A CN 103526174A
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- magnesium alloy
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Abstract
The invention discloses a surface modification method for delaying the degradation rate of a biomedical magnesium alloy. The method comprises the following steps of pre-processing the magnesium alloy, injecting ions and post-processing, wherein pre-processing the magnesium alloy comprises grinding, polishing, cleaning and drying sequentially; in the step of injecting the ions, the processed magnesium alloy is put into a cavity of an ion injection machine and vacuumized, the injection dose is set and an extraction power supply is turned on after an ion source pre-heats for 10 minutes, the extraction voltage is regulated, and the ions are injected into the surface, wherein the injection mode is that the gadolinium ions are injected and then the neodymium ions are injected, the injection dose of the gadolinium ions is 2.5*10<16>-1*10<17> ions/cm<2>, and the injection dose of the neodymium ions is 5*10<16>-1.5*10<17> ions/cm<2>; and in the step of post-processing, the magnesium alloy with the ions injected is cleaned, dried and saved. The surface modification method for delaying the degradation rate of the biomedical magnesium alloy, provided by the invention, is simple in process, has no pollution to the environment, can delay the degradation rate of the biomedical magnesium alloy in a human body, prolongs the service life of a magnesium alloy medical implantation device, causes no harm to the human body and has a relatively good biocompatibility, and the application scope of the magnesium alloy is expanded.
Description
Technical field
The present invention relates to a kind of surface modifying method that delays biological medical magnesium alloy degradation rate, belong to Metal Surface Modification Technique field.
Background technology
Due to the biocompatibility of magnesium alloy excellence, and the comprehensive mechanical property such as Young's modulus and skeleton approach, so magnesium alloy is subject to people in fields such as biomedicines and more and more pays close attention to.But magnesium alloy chemical activity is high, fast degradation in physiological environment very easily, this has seriously hindered its development and application in biomedical sector.Therefore the degradation rate of, effectively controlling magnesium alloy has vital role to expanding magnesium alloy medical use.
Common Magnesiumalloy surface modifying technology mainly contains alloying, chemical conversion, vapour deposition, anodic oxidation, plating, Laser Surface Treatment and ion implantation etc., wherein, alloying is to improve at present the major measure of magnesium alloy degradation behavior, but in alloying process, needs to consume many rare earth metals.Ion implantation is the important means of improving abrasion-resistant metal, the surface property such as anti-corrosion and anti-oxidant, this technique consumable quantity is little, technological process is not limited by conventional thermodynamic condition, can accurately control the dosage and the energy that inject element, and the part dimension after noting does not change substantially, there is not abrupt interface and the rete problem that comes off in modified layer yet.
Through existing technical literature retrieval, find, although existing a variety of for the injection element of magnesium alloy modification, as Al, Ti, Ta, Ce, Zr etc., and the research of the rare earth element ion injection magnesium alloy such as relevant Gd, Nd there is not yet report.Up to the present, both at home and abroad to magnesium alloy altogether the research of notes aspect also mostly only limit to the common notes research of metal-elemental gas, as Ti/N(Liu Hong happiness, the first month of spring flower bud, Lin Bo, Deng. nitrogen titanium double ion injects the anticorrosive and mechanical property [J] of AZ31 magnesium alloy. material heat treatment journal, 2011, 32 (8): 137-141), Ti/O(Y Zhao, G.S Wu, Q.Y Lu, et al. Improved surface corrosion resistance of WE43 magnesium alloy by dual titanium and oxygen ion implantation[J] .Thin Solid Films, 2013, 529:407-411) etc., and for the metal-metal element of magnesium alloy, the technical study that particularly rare earth metal-thulium is noted altogether there is not yet report.
Summary of the invention
Object: in order to overcome the deficiencies in the prior art, the invention provides a kind of surface modifying method that delays biological medical magnesium alloy degradation rate, use the method can effectively slow down the degradation behavior of magnesium alloy etc., expands the range of application of magnesium alloy.
Technical scheme: for solving the problems of the technologies described above, the technical solution used in the present invention is:
A surface modifying method that delays biological medical magnesium alloy degradation rate, is characterized in that, comprises the following steps:
Ion implantation: clean magnesium alloy to be put into ion implanter chamber, and be evacuated to vacuum; After ion source preheating 10min, implantation dosage be set and open and draw power supply, regulating extraction voltage, to its surface, carrying out ion implantation; Along with implantation dosage increases, input horizon meeting progressive additive, to the implantation dosage value of reaching capacity, wherein injection mode is: after first injecting gadolinium ion, inject neodymium ion; Gadolinium ion implantation dosage is 2.5 * 10
16~ 1 * 10
17ions/cm
2, neodymium ion implantation dosage 5 * 10
16~ 1.5 * 10
17ions/cm
2.
As preferred version, described a kind of surface modifying method that delays biological medical magnesium alloy degradation rate, is characterized in that: describedly also comprise magnesium alloy pre-treatment step before ion implantation: comprise successively polishing, polishing, clean and dry up;
After ion implantation, also comprise aftertreatment: the magnesium alloy after ion implantation is cleaned, then dry up preservation.
As preferred version, described polishing is successively with 280 orders, 400 orders, 800 orders and 1000 object abrasive paper for metallograph polishing Mg alloy surface, removal surface contaminant; And/or described polishing is to make rumbling compound with MgO, is polished to minute surface; And/or described cleaning is ultrasonic cleaning 10min in ethanol; And/or described drying up is to adopt cold wind to dry up.
As preferred version, described magnesium alloy is a kind of in magnalium zinc series magnesium alloy, magnesium zinc series magnesium alloy, Rare Earth magnesium alloy.
As preferred version, described magnalium zinc series magnesium alloy is AZ31 magnesium alloy or AZ91 magnesium alloy; And/or magnesium zinc series magnesium alloy is Mg-Zn magnesium alloy or ZK60 magnesium alloy; And/or magnesium-rare earth is Mg-2.0Nd-0.3Sr-0.4Zr magnesium alloy.
As preferred version, described in be evacuated to vacuum tightness≤2 * 10 that vacuum is chamber
-3pa, and/or described adjusting extraction voltage is 60kV.
As preferred version, described cleaning is ultrasonic cleaning 5min in distilled water, and/or described drying up is to adopt cold wind to dry up.
Beneficial effect: a kind of surface modifying method that delays biological medical magnesium alloy degradation rate provided by the invention, technique is simple, injecting ion is gadolinium and neodymium, because gadolinium, neodymium itself have excellent corrosion resisting property, and gadolinium, neodymium element can Refining Mg Alloy crystal grain, to improving its mechanical property and degradation behavior, play an important role; The more important thing is, gadolinium, neodymium element are harmless, have good biocompatibility, and gadolinium element has dilating effect to blood vessel, and neodymium element can keep cytotoxicity in lower level; Environmentally safe, can effectively slow down magnesium alloy degradation speed in vivo, extend the service life of magnesium alloy medical treatment implantation equipment, and the injection ion that degradation process is separated out has positive pharmacological action, this will widen the range of application of magnesium alloy in medical science greatly; The method, than conventional alloys metallization processes consumption rare earth element still less, has been saved rare earth resources in addition.
Accompanying drawing explanation
Fig. 1 is that gadolinium, the neodymium ion in the present invention noted the polarization curve of AZ31 magnesium alloy in simulated body fluid altogether;
Wherein, (a) curve: do not inject gadolinium, neodymium ion; (b) curve: first inject gadolinium ion 2.5 * 10
16ions/cm
2after Gd, inject neodymium ion 5 * 10
16ions/cm
2nd.
Embodiment
The gadolinium, the neodymium ion that are different implantation dosages are below noted the several embodiment in magnalium zinc series magnesium alloy (AZ31, AZ91), magnesium zinc series magnesium alloy (Mg-Zn, ZK60), Rare Earth magnesium alloy (Mg-2.0Nd-0.3Sr-0.4Zr) altogether, to be further described for the technical program.
Embodiment 1
Using AZ31 magnesium alloy as base material, and its composition is: Al3%, and Zn1%, all the other are Mg.The surface modifying method that delays biological medical magnesium alloy degradation rate is: first AZ31 Mg alloy surface is polished with 280,400,800 and 1000 object abrasive paper for metallograph successively, remove surface contaminant, and be polished to minute surface; Use ethanol ultrasonic cleaning, cold wind dries up again; Then put into the vacuum chamber of ion implanter, treat that vacuum tightness is evacuated to 2 * 10
-3below Pa, inject neodymium ion after first injecting gadolinium ion to its surface, implantation temperature is room temperature, and extraction voltage is 60kV, and implantation dosage is gadolinium ion 2.5 * 10
16ions/cm
2, neodymium ion 5 * 10
16ions/cm
2; After injection finishes, inflation, takes out sample, cleans and dries up.The polarization curve test of sample in simulated body fluid (SBF) shows (as shown in Figure 1), after AZ31 magnesium alloy gadolinium, neodymium ion are noted altogether, and be elevated to-1.35V of corrosion voltage, corrosion electric current density is reduced to 6.39 * 10
-6a/cm
2, compare with base material, the corrosion voltage of the AZ31 magnesium alloy after the injection 0.24V that raise, it is many that corrosion electric current density has reduced an order of magnitude, illustrates and note altogether 2.5 * 10
16ions/cm
2gd+5 * 10
16ions/cm
2the gadolinium of Nd, neodymium ion have slowed down the degradation speed of AZ31 magnesium alloy in physiological environment significantly.
Using AZ91 magnesium alloy as base material, and its composition is: Al9%, and Zn1%, all the other are Mg.It is identical with embodiment 1 that gadolinium, neodymium ion are noted process altogether, and different is that implantation dosage is 2.5 * 10
16ions/cm
2gd+1 * 10
17ions/cm
2nd.Sample records corrosion voltage in mould SBF, exceeds matrix 0.1V, and corrosion current is about 1.52 * 10
-5a/cm
2, than the low nearly order of magnitude of matrix, illustrate and note altogether 2.5 * 10
16ions/cm
2gd+1 * 10
17ions/cm
2after the gadolinium of Nd, neodymium ion, the degradation behavior of AZ91 magnesium alloy obtains larger alleviation.
Embodiment 3
Using Mg-Zn magnesium alloy as base material, and its composition is: Zn5.6%, all the other are Mg.It is identical with embodiment 1 that gadolinium, neodymium ion are noted process altogether, and different is that implantation dosage is gadolinium ion 5 * 10
16ions/cm
2, neodymium ion 1.5 * 10
17ions/cm
2.The corrosion voltage of Mg-Zn magnesium alloy after noting altogether in SBF does not change substantially, and corrosion electric current density reduces to 5.13 * 10
-5a/cm
2, reduced by 7 times of left and right, illustrate that Mg-Zn magnesium alloy is through 5 * 10
16ions/cm
2gd+1.5 * 10
17ions/cm
2after the gadolinium of Nd, neodymium ion are noted altogether, its degradation speed is reduced.
Embodiment 4
Using ZK60 magnesium alloy as base material, and its composition is: Zn5.5%, and Zr0.45%, all the other are Mg.It is identical with embodiment 1 that gadolinium, neodymium ion are noted process altogether, and different is that implantation dosage is gadolinium ion 5 * 10
16ions/cm
2gd, neodymium ion 1 * 10
17ions/cm
2nd.The polarization curve of sample in SBF tested and shown, gadolinium, neodymium ion are noted after ZK60 magnesium alloy altogether, be elevated to-1.4V of corrosion voltage, and corrosion electric current density is reduced to 4.55 * 10
-6a/cm
2, compare with base material, the corrosion voltage of the ZK60 magnesium alloy after the injection 0.07V that raise, corrosion electric current density reduces approximately 5 times, illustrates and notes altogether 5 * 10
16ions/cm
2gd+1 * 10
17ions/cm
2after the gadolinium of Nd, neodymium ion, ZK60 magnesium alloy degradation behavior has necessarily and slows down.
Using Mg-2.0Nd-0.3Sr-0.4Zr magnesium alloy as base material, and its composition is: Nd2%, and Sr0.3%, Zr0.4%, all the other are Mg.It is identical with embodiment 1 that gadolinium, neodymium ion are noted process altogether, and different is that implantation dosage is gadolinium ion 1 * 10
17ions/cm
2gd, neodymium ion 1 * 10
17ions/cm
2nd.The test of the solidity to corrosion of sample in SBF shows, Mg-2.0Nd-0.3Sr-0.4Zr magnesium alloy is noted after gadolinium, neodymium ion altogether, the corrosion voltage 0.12V that raise, and corrosion electric current density is reduced to 2.23 * 10
-5a/cm
2, reduced nearly order of magnitude, illustrate and note altogether 1 * 10
17ions/cm
2gd+1 * 10
17ions/cm
2after the gadolinium of Nd, neodymium ion, the degradation speed of Mg-2.0Nd-0.3Sr-0.4Zr magnesium alloy is retarded.
The above is only the preferred embodiment of the present invention; be noted that for those skilled in the art; under the premise without departing from the principles of the invention, can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.
Claims (7)
1. a surface modifying method that delays biological medical magnesium alloy degradation rate, is characterized in that, comprises the following steps:
Ion implantation: clean magnesium alloy to be put into ion implanter chamber, and be evacuated to vacuum; After ion source preheating 10min, implantation dosage be set and open and draw power supply, regulating extraction voltage, to its surface, carrying out ion implantation; Along with implantation dosage increases, input horizon meeting progressive additive, to the implantation dosage value of reaching capacity, wherein injection mode is: after first injecting gadolinium ion, inject neodymium ion; Gadolinium ion implantation dosage is 2.5 * 10
16~ 1 * 10
17ions/cm
2, neodymium ion implantation dosage 5 * 10
16~ 1.5 * 10
17ions/cm
2.
2. a kind of surface modifying method that delays biological medical magnesium alloy degradation rate according to claim 1, is characterized in that: describedly also comprise magnesium alloy pre-treatment step before ion implantation: comprise successively polishing, polishing, clean and dry up;
After ion implantation, also comprise aftertreatment: the magnesium alloy after ion implantation is cleaned, then dry up preservation.
3. a kind of surface modifying method that delays biological medical magnesium alloy degradation rate according to claim 2, it is characterized in that: described polishing is successively with 280 orders, 400 orders, 800 orders and 1000 object abrasive paper for metallograph polishing Mg alloy surface, removal surface contaminant; And/or described polishing is to make rumbling compound with MgO, is polished to minute surface; And/or described cleaning is ultrasonic cleaning 10min in ethanol; And/or described drying up is to adopt cold wind to dry up.
4. a kind of surface modifying method that delays biological medical magnesium alloy degradation rate according to claim 1, is characterized in that: described magnesium alloy is a kind of in magnalium zinc series magnesium alloy, magnesium zinc series magnesium alloy, Rare Earth magnesium alloy.
5. a kind of surface modifying method that delays biological medical magnesium alloy degradation rate according to claim 4, is characterized in that: described magnalium zinc series magnesium alloy is AZ31 magnesium alloy or AZ91 magnesium alloy; And/or magnesium zinc series magnesium alloy is Mg-Zn magnesium alloy or ZK60 magnesium alloy; And/or magnesium-rare earth is Mg-2.0Nd-0.3Sr-0.4Zr magnesium alloy.
6. a kind of surface modifying method that delays biological medical magnesium alloy degradation rate according to claim 2, is characterized in that: described in be evacuated to vacuum tightness≤2 * 10 that vacuum is chamber
-3pa, and/or described adjusting extraction voltage is 60kV.
7. a kind of surface modifying method that delays biological medical magnesium alloy degradation rate according to claim 2, is characterized in that: described cleaning is ultrasonic cleaning 5min in distilled water, and/or described drying up is to adopt cold wind to dry up.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107805792A (en) * | 2017-11-06 | 2018-03-16 | 南京工程学院 | A kind of method for improving biologic medical magnesium surface property and corrosive wear behavior |
| CN109355651A (en) * | 2018-10-23 | 2019-02-19 | 吴桂菁 | A kind of chemical composition coating of Mg alloy surface and preparation method thereof |
| CN113073303A (en) * | 2021-03-26 | 2021-07-06 | 南京工程学院 | Biomedical pure magnesium surface functional structured ion implantation modified layer and preparation method and application thereof |
| CN115772622A (en) * | 2021-09-06 | 2023-03-10 | 武汉苏泊尔炊具有限公司 | Cooking utensil and preparation method thereof |
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| CN102345103A (en) * | 2011-09-23 | 2012-02-08 | 佳木斯大学 | Preparation method of titanium modified layer on surface of magnesium and lithium alloy |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107805792A (en) * | 2017-11-06 | 2018-03-16 | 南京工程学院 | A kind of method for improving biologic medical magnesium surface property and corrosive wear behavior |
| CN109355651A (en) * | 2018-10-23 | 2019-02-19 | 吴桂菁 | A kind of chemical composition coating of Mg alloy surface and preparation method thereof |
| CN113073303A (en) * | 2021-03-26 | 2021-07-06 | 南京工程学院 | Biomedical pure magnesium surface functional structured ion implantation modified layer and preparation method and application thereof |
| CN113073303B (en) * | 2021-03-26 | 2021-11-16 | 南京工程学院 | Biomedical pure magnesium surface functional structured ion implantation modified layer and preparation method and application thereof |
| CN115772622A (en) * | 2021-09-06 | 2023-03-10 | 武汉苏泊尔炊具有限公司 | Cooking utensil and preparation method thereof |
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