CN104328312A - Medical biodegradable zinc alloy and preparation method thereof - Google Patents
Medical biodegradable zinc alloy and preparation method thereof Download PDFInfo
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- CN104328312A CN104328312A CN201410556876.4A CN201410556876A CN104328312A CN 104328312 A CN104328312 A CN 104328312A CN 201410556876 A CN201410556876 A CN 201410556876A CN 104328312 A CN104328312 A CN 104328312A
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- 229910001297 Zn alloy Inorganic materials 0.000 title claims abstract description 35
- 238000002360 preparation method Methods 0.000 title claims abstract description 13
- 239000011701 zinc Substances 0.000 claims abstract description 38
- 229910052751 metal Inorganic materials 0.000 claims abstract description 35
- 239000002184 metal Substances 0.000 claims abstract description 34
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims abstract description 29
- 238000000137 annealing Methods 0.000 claims abstract description 29
- 229910052725 zinc Inorganic materials 0.000 claims abstract description 29
- 239000011575 calcium Substances 0.000 claims abstract description 25
- 238000001816 cooling Methods 0.000 claims abstract description 25
- 229910052791 calcium Inorganic materials 0.000 claims abstract description 24
- 238000005266 casting Methods 0.000 claims abstract description 24
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims abstract description 22
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims abstract description 17
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 claims abstract description 17
- VHHHONWQHHHLTI-UHFFFAOYSA-N hexachloroethane Chemical compound ClC(Cl)(Cl)C(Cl)(Cl)Cl VHHHONWQHHHLTI-UHFFFAOYSA-N 0.000 claims abstract description 15
- 239000011777 magnesium Substances 0.000 claims abstract description 14
- 229910052709 silver Inorganic materials 0.000 claims abstract description 10
- 239000011572 manganese Substances 0.000 claims abstract description 9
- 239000012535 impurity Substances 0.000 claims abstract description 8
- 229910045601 alloy Inorganic materials 0.000 claims description 63
- 239000000956 alloy Substances 0.000 claims description 63
- 238000000034 method Methods 0.000 claims description 36
- 238000009413 insulation Methods 0.000 claims description 33
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 16
- 239000000203 mixture Substances 0.000 claims description 15
- 230000008569 process Effects 0.000 claims description 14
- 238000005096 rolling process Methods 0.000 claims description 12
- 230000003628 erosive effect Effects 0.000 claims description 10
- 229910052748 manganese Inorganic materials 0.000 claims description 8
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 7
- 229910002804 graphite Inorganic materials 0.000 claims description 7
- 239000010439 graphite Substances 0.000 claims description 7
- 238000002844 melting Methods 0.000 claims description 7
- 230000008018 melting Effects 0.000 claims description 7
- 239000002994 raw material Substances 0.000 claims description 7
- 238000010792 warming Methods 0.000 claims description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
- 208000016261 weight loss Diseases 0.000 claims description 7
- 230000004580 weight loss Effects 0.000 claims description 7
- 238000001125 extrusion Methods 0.000 claims description 5
- 238000005242 forging Methods 0.000 claims description 4
- 238000000265 homogenisation Methods 0.000 claims description 4
- 238000011282 treatment Methods 0.000 claims description 4
- 239000000463 material Substances 0.000 abstract description 19
- 238000010438 heat treatment Methods 0.000 abstract description 3
- 239000004332 silver Substances 0.000 abstract description 3
- 238000003825 pressing Methods 0.000 abstract 1
- 238000003756 stirring Methods 0.000 abstract 1
- 238000006731 degradation reaction Methods 0.000 description 8
- 239000007943 implant Substances 0.000 description 8
- 230000015556 catabolic process Effects 0.000 description 7
- 229910052749 magnesium Inorganic materials 0.000 description 6
- 230000007797 corrosion Effects 0.000 description 4
- 238000005260 corrosion Methods 0.000 description 4
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 3
- 229910000861 Mg alloy Inorganic materials 0.000 description 3
- 238000005275 alloying Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 239000007769 metal material Substances 0.000 description 2
- 230000001988 toxicity Effects 0.000 description 2
- 231100000419 toxicity Toxicity 0.000 description 2
- 206010061218 Inflammation Diseases 0.000 description 1
- 241000446313 Lamella Species 0.000 description 1
- 229910001069 Ti alloy Inorganic materials 0.000 description 1
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 1
- 230000000975 bioactive effect Effects 0.000 description 1
- 210000000988 bone and bone Anatomy 0.000 description 1
- 230000000747 cardiac effect Effects 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 235000005911 diet Nutrition 0.000 description 1
- 230000000378 dietary effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 230000003203 everyday effect Effects 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 238000000338 in vitro Methods 0.000 description 1
- 208000015181 infectious disease Diseases 0.000 description 1
- 230000004054 inflammatory process Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 210000004185 liver Anatomy 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 230000003387 muscular Effects 0.000 description 1
- 238000011587 new zealand white rabbit Methods 0.000 description 1
- 229910052758 niobium Inorganic materials 0.000 description 1
- 239000010955 niobium Substances 0.000 description 1
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 description 1
- 230000008520 organization Effects 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 239000010970 precious metal Substances 0.000 description 1
- 210000005084 renal tissue Anatomy 0.000 description 1
- 229910001285 shape-memory alloy Inorganic materials 0.000 description 1
- -1 silver ions Chemical class 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 230000001954 sterilising effect Effects 0.000 description 1
- 238000004659 sterilization and disinfection Methods 0.000 description 1
- 229910052715 tantalum Inorganic materials 0.000 description 1
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 238000004154 testing of material Methods 0.000 description 1
- 238000007669 thermal treatment Methods 0.000 description 1
- 210000001519 tissue Anatomy 0.000 description 1
- 231100000820 toxicity test Toxicity 0.000 description 1
- 239000011573 trace mineral Substances 0.000 description 1
- 235000013619 trace mineral Nutrition 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Abstract
The invention discloses a medical biodegradable zinc alloy and a preparation method thereof, belonging to the technical field of materials. The medical biodegradable zinc alloy comprises the following components in percentage by weight: 0.005-1% of Mg, 0.01-0.5% of Ag, 0.01-0.5% of Ca, 0.01-0.5% of Mn, less than or equal to 0.2% of inevitable impurities and the balance of Zn. The preparation method comprises the following steps: (1) heating pure metal zinc to be 520+/-5 DEG C, dissolving, sequentially adding manganese metal, metallic silver, calcium metal and magnesium metal, and stirring till the components are uniformly mixed; (2) cooling to be 460+/-5 DEG C, pressing hexachloroethane, keeping the temperature, and standing for 10-20 minutes; (3) keeping and reducing the temperature to be 440+/-5 DEG C, and casting; (4) keeping the temperature to be 300+/-5 DEG C for 100-200 minutes, heating to be 330-360 DEG C, keeping the temperature for 3-5 hours, and further water-cooling to be normal temperature; (5) keeping the temperature to be 150-350 DEG C for 20-40 minutes, subsequently performing high-temperature deformation, and air-cooling to be normal temperature; and (6) performing multiple times of normal temperature deformation-intermediate annealing, and finally air-cooling to be the normal temperature. The zinc alloy disclosed by the invention can be used for preparing various degradable medical devices which can meet different clinical use requirements.
Description
Technical field
The invention belongs to field of material technology, particularly a kind of medical bio degradable zinc alloy and preparation method thereof.
Background technology
Metallic substance becomes current clinical application embedded material more widely due to its good mechanical property and processing characteristics, mainly comprises pure metal (tantalum, niobium, zirconium etc.), stainless steel, titanium alloy, cobalt base alloy, shape memory alloy, precious metal etc.; These materials all have good corrosion resistance nature, can stable for extended periods of time after implant into body; But also bring some problems, such as, need second operation to take out; Alloying element discharges and brings the detrimentally affects such as potential hazard to human body.
In order to avoid the problem that above-mentioned embedded material causes, propose the technology using degradable embedded material.The degradable embedded material of current clinical application mainly comprises macromolecular material and biological active ceramic material, but this kind of degradation material still exists obvious defect: Polymer Mechanical performance is too low, the sour environment that degraded produces can increase the possibility that inflammation produces; The plasticity of bioactive ceramics and toughness are all poor, thus limit its range of application.Metal current base degradable embedded material not yet obtains clinical application, still underway to its R and D, and mainly concentrates on magnesium alloy and ferrous alloy.But magnesium alloy and ferrous alloy exist some problems as degradable embedded material in degradation rate, the maximum problem of magnesium alloy is that its degradation speed is too fast, affects its biocompatibility and mechanical property in use; And the maximum problem of ferrous alloy is that degradation speed is excessively slow, can cause a series of untoward reaction similar with bio-inert material.
The chemically reactive of metallic zinc is between magnesium and iron, so its erosion rate is expected between therebetween, thus can to prepare the suitable material of degradation rate.In addition zinc is one of necessary trace element of human body, Zn content in adult body is 1.4 ~ 2.3g, the allowance,dietary of health adult's zinc every day is 15 ~ 40mg, and therefore zinc has certain advantage as degradable embedded material in the control and biological safety of degradation rate.But the mechanical property of pure zinc is poor, intensity and plasticity all can not meet the requirement of embedded material.
Summary of the invention
The object of this invention is to provide a kind of medical bio degradable zinc alloy and preparation method thereof, harmless metallic element is selected to carry out alloying, then alloy is by thermal distortion, cold deformation and thermal treatment, obtains high strength, good plasticity, degradable zinc alloy medical degradable material.
The composition of medical bio degradable zinc alloy of the present invention is by weight percentage containing Mg 0.005 ~ 1%, Ag 0.01 ~ 0.5%, Ca 0.01 ~ 0.5%, Mn 0.01 ~ 0.5%, and inevitable impurity≤0.2%, surplus is Zn.
The tensile strength of above-mentioned medical bio degradable zinc alloy is 260 ~ 450MPa, and tensile yield strength is 195 ~ 380MPa, unit elongation 5 ~ 30%.
The preparation method of medical bio degradable zinc alloy of the present invention carries out according to the following steps:
(1) metallic zinc, MAGNESIUM METAL, argent, calcium metal and manganese metal is prepared as raw material by mentioned component; Pure metal zinc is heated to 520 ± 5 DEG C, after metallic zinc is dissolved, adds manganese metal, argent, calcium metal and MAGNESIUM METAL successively, after whole melting of metal, be stirred to and mix, obtain alloy melt;
(2) alloy melt is cooled to 460 ± 5 DEG C, utilizes graphite bell jar to be pressed into hexachloroethane in alloy melt, the hexachloroethane of press-in is 0.2 ~ 0.3% of alloy melt gross weight, then leaves standstill 10 ~ 20min 460 ± 5 DEG C of insulations;
(3) after the standing end of insulation, alloy melt being cooled to 440 ± 5 DEG C is poured in mould, and in casting cycle, die through water cooling, obtains ingot casting;
(4) ingot casting carries out Homogenization Treatments, and Homogenization Treatments is at 300 DEG C ± 5 insulation 100 ~ 200min; Then be warming up to 330 ~ 360 DEG C of insulations 3 ~ 5 hours, then water-cooled is to normal temperature, obtains ingot blank;
(5) ingot blank is incubated 20 ~ 40min at 150 ~ 350 DEG C, then carry out high temperature plastic distortion at 150 ~ 350 DEG C, then air cooling is to normal temperature, obtain heat-altered morphology alloy; Described high temperature plastic is deformed into extruding, rolling or forging, and when extruding, extrusion ratio is 16 ~ 150; When being rolled or forge, total deformation is 50 ~ 80%;
(6) heat-altered morphology alloy is carried out repeatedly normal temperature distortion-process annealing, each normal temperature distortion is divided into multi pass drawing or rolling, and the deflection of every time drawing or rolling is 8 ~ 20%, and the total deformation of each normal temperature distortion is 60 ~ 80%; Carry out a process annealing after each normal temperature distortion, intermediate anneal temperature is 150 ~ 300 DEG C, and the time is 10 ~ 20min; When the total deformation of repeatedly normal temperature distortion-process annealing reaches 92 ~ 98%, after process annealing, air cooling, to normal temperature, obtains medical bio degradable zinc alloy the last time.
In aforesaid method, the tensile strength of heat-altered morphology alloy is 220 ~ 400MPa, and tensile yield strength is 160 ~ 360MPa, unit elongation 12 ~ 40%.
Above-mentioned medical bio degradable zinc alloy is sheet material, bar or wire rod.
Above-mentioned step 1 and 2 heating installations adopted are resistance furnace.
The ingot casting that above-mentioned step 3 obtains is diameter be the cylindrical of 40 ~ 60mm or the length of side is the square of 40 ~ 60mm.
Above-mentioned medical bio degradable zinc alloy adopts weight-loss method, and in 37 DEG C of SBF solution, record its erosion rate is 0.2 ~ 0.8mm/year.
The invention has the advantages that:
1, in medical bio degradable zinc alloy, zinc, magnesium, calcium, manganese are the element that human body itself contains, and the silver of trace is harmless to human body, and can silver ions be discharged in its degradation process, play the effect of sterilization, can avoid causing infection after device is implanted, thus alleviate misery and the trouble of patient;
2, medical bio degradable zinc alloy is processed by modes such as extruding, rolling, forging or drawings, obtains rod, line, plate and section bar; Its mechanical property can be made significantly to be changed by the small adjustment of alloying element content, yield strength >200MPa can be reached, the performance requriements of unit elongation >15%, and its degradation rate can be controlled reach about 0.5mm/year;
3, the rod of medical bio degradable zinc alloy, line, plate and profile size variation range wider (Φ 0.05 ~ 12mm or t0.1 ~ 20mm), may be used for the preparation of different implant devices, such as nail, hone lamella, angiocarpy bracket, bone tissue engineering scaffold, suture line and make matrix material device etc. with other materials, can be used for preparing various degradable device to meet different Clinical practice requirements.
Accompanying drawing explanation
Fig. 1 is the general toxicity test-results of the medical bio degradable zinc alloy of preparation in the embodiment of the present invention 1; Wherein (a) cardiac muscular tissue; (b) liver organization; (c) renal tissue;
Fig. 2 extrudes the zinc alloy that obtains to implant X-ray image after new zealand white rabbit, after wherein (a) implants one week in the embodiment of the present invention 1; B () implants after one month; C () implants after three months;
Fig. 3 is the metallographic structure photo figure of heat-altered morphology alloy in the embodiment of the present invention 1;
Fig. 4 is heat-altered morphology Alloy At Room Temperature tensile property graphic representation in the embodiment of the present invention 1;
Fig. 5 is that the medical bio degradable zinc alloy of the embodiment of the present invention 1 and pure magnesium soak macro morphology figure after 8 days in 37 DEG C of SBF solution, and wherein (a) is biodegradable zinc alloy medical in the embodiment of the present invention 1, and (b) is pure magnesium;
Fig. 6 be the medical bio degradable zinc alloy of the embodiment of the present invention 1 and pure magnesium in 37 DEG C of SBF solution under soaking conditions, erosion rate is with soak time change curve; In figure, ◆ be pure magnesium, ▼ is medical bio degradable zinc alloy;
Fig. 7 is the alloy microstructure photo figure in the embodiment of the present invention 1 after normal temperature distortion;
Fig. 8 is the Alloy At Room Temperature tensile property graphic representation in the embodiment of the present invention 1 after normal temperature distortion.
Embodiment
The purity of the metallic zinc adopted in the embodiment of the present invention is 99.995%, and MAGNESIUM METAL purity is 99.99%, and argent purity is 99.99%, and calcium metal purity is 99.95%, and manganese metal purity is 99.995%.
In the embodiment of the present invention, the testing method of general toxicity test is according to GB/T 16886.11-1997 BiologicalEvaluationofMedicalDevice the 11st part: general toxicity touchstone.
The equipment observing metallographic structure adopt in the embodiment of the present invention is the GX71 inversion type system gold phase microscope that OLYMPUS company produces.
In the embodiment of the present invention, tension test accepted standard is GB GB/T 228-2002 " metallic substance normal temperature stretching test method ", and equipment is produced AG-X100kN electronic universal material testing machine by being made Co., Ltd. by Shimadzu
In the embodiment of the present invention, test performance accepted standard is standard GB/T/T16545-1996 " corrosion of metal and alloy---the removing of corrosion product on corrosion sample ", and SBF solution preparation is according to ISO/FDIS23317:Implants for surgery---In vitro evaluation for apatite-forming ability of implant materials carries out.
Ingot casting in the embodiment of the present invention to be diameter be the cylindrical of 40 ~ 60mm or the length of side 40 ~ 60mm's is square.
Embodiment 1
Composition contains Mg 0.05%, Ag 0.5%, Ca 0.1%, Mn 0.1% by weight percentage, inevitable impurity≤0.2%, and surplus is Zn;
Metallic zinc, MAGNESIUM METAL, argent, calcium metal and manganese metal are as raw material; Pure metal zinc is heated to 520 ± 5 DEG C, after metallic zinc is dissolved, adds manganese metal, argent, calcium metal and MAGNESIUM METAL successively, after whole melting of metal, be stirred to and mix, obtain alloy melt;
Alloy melt is cooled to 460 ± 5 DEG C, utilizes graphite bell jar to be pressed into hexachloroethane in alloy melt, the hexachloroethane of press-in is 0.2% of alloy melt gross weight, then leaves standstill 20min 460 ± 5 DEG C of insulations;
Alloy melt is cooled to 440 ± 5 DEG C after leaving standstill and terminating and is poured in mould by insulation, and in casting cycle, die through water cooling, obtains ingot casting;
Ingot casting, at 300 DEG C ± 5 insulation 100min, be then warming up to 360 DEG C of insulations 3 hours, then water-cooled is to normal temperature, is obtained ingot blank;
By ingot blank at 200 DEG C of insulation 40min, then high temperature plastic distortion is carried out at 200 DEG C, air cooling is to normal temperature again, obtain heat-altered morphology alloy, tensile strength is 220MPa, and tensile yield strength is 160MPa, unit elongation 17%, as shown in Figure 3, room temperature tensile properties curve as shown in Figure 4 for the metallographic structure photo of heat-altered morphology alloy;
Described high temperature plastic is deformed into extruding, and extrusion ratio is 16;
Heat-altered morphology alloy is carried out repeatedly normal temperature distortion-process annealing, each normal temperature distortion is divided into multi pass drawing, and the deflection of every time drawing is 8 ~ 20%, and the total deformation of each normal temperature distortion is 60 ~ 80%; Carry out a process annealing after each normal temperature distortion, intermediate anneal temperature is 300 DEG C, and the time is 10min; When the total deformation of repeatedly normal temperature distortion-process annealing reaches 92%, after process annealing, air cooling is to normal temperature the last time, and obtain medical bio degradable zinc alloy, tensile strength is 260MPa, and tensile yield strength is 195MPa, unit elongation 14%; Adopt weight-loss method, in 37 DEG C of SBF solution, record its erosion rate is 0.2mm/year, and with soak time change curve as shown in Figure 6, as shown in Figure 7, room temperature tensile properties curve as shown in Figure 8 for the alloy microstructure photo after normal temperature distortion for erosion rate.
Embodiment 2
Composition contains Mg 1%, Ag 0.01%, Ca 0.5%, Mn 0.01% by weight percentage, inevitable impurity≤0.2%, and surplus is Zn;
Metallic zinc, MAGNESIUM METAL, argent, calcium metal and manganese metal are as raw material; Pure metal zinc is heated to 520 ± 5 DEG C, after metallic zinc is dissolved, adds manganese metal, argent, calcium metal and MAGNESIUM METAL successively, after whole melting of metal, be stirred to and mix, obtain alloy melt;
Alloy melt is cooled to 460 ± 5 DEG C, utilizes graphite bell jar to be pressed into hexachloroethane in alloy melt, the hexachloroethane of press-in is 0.25% of alloy melt gross weight, then leaves standstill 10min 460 ± 5 DEG C of insulations;
Alloy melt is cooled to 440 ± 5 DEG C after leaving standstill and terminating and is poured in mould by insulation, and in casting cycle, die through water cooling, obtains ingot casting;
Ingot casting, at 300 DEG C ± 5 insulation 150min, be then warming up to 330 DEG C of insulations 5 hours, then water-cooled is to normal temperature, is obtained ingot blank;
By ingot blank at 250 DEG C of insulation 30min, then carry out high temperature plastic distortion at 250 DEG C, then air cooling is to normal temperature, obtain heat-altered morphology alloy, tensile strength is 400MPa, and tensile yield strength is 60340MPa, unit elongation 12%;
Described high temperature plastic is deformed into extruding, and extrusion ratio is 150;
Heat-altered morphology alloy is carried out repeatedly normal temperature distortion-process annealing, each normal temperature distortion is divided into multi-pass rolling, and the deflection of every time rolling is 8 ~ 20%, and the total deformation of each normal temperature distortion is 60 ~ 80%; Carry out a process annealing after each normal temperature distortion, intermediate anneal temperature is 150 DEG C, and the time is 20min; When the total deformation of repeatedly normal temperature distortion-process annealing reaches 94%, after process annealing, air cooling is to normal temperature the last time, and obtain medical bio degradable zinc alloy, tensile strength is 450MPa, and tensile yield strength is 380MPa, unit elongation 5%; Adopt weight-loss method, in 37 DEG C of SBF solution, record its erosion rate is 0.6mm/year.
Embodiment 3
Composition contains Mg 0.005%, Ag 0.1%, Ca 0.15%, Mn 0.15% by weight percentage, inevitable impurity≤0.2%, and surplus is Zn;
Metallic zinc, MAGNESIUM METAL, argent, calcium metal and manganese metal are as raw material; Pure metal zinc is heated to 520 ± 5 DEG C, after metallic zinc is dissolved, adds manganese metal, argent, calcium metal and MAGNESIUM METAL successively, after whole melting of metal, be stirred to and mix, obtain alloy melt;
Alloy melt is cooled to 460 ± 5 DEG C, utilizes graphite bell jar to be pressed into hexachloroethane in alloy melt, the hexachloroethane of press-in is 0.3% of alloy melt gross weight, then leaves standstill 20min 460 ± 5 DEG C of insulations;
Alloy melt is cooled to 440 ± 5 DEG C after leaving standstill and terminating and is poured in mould by insulation, and in casting cycle, die through water cooling, obtains ingot casting;
Ingot casting, at 300 DEG C ± 5 insulation 200min, be then warming up to 340 DEG C of insulations 3 hours, then water-cooled is to normal temperature, is obtained ingot blank;
By ingot blank at 350 DEG C of insulation 20min, then carry out high temperature plastic distortion at 350 DEG C, then air cooling is to normal temperature, obtain heat-altered morphology alloy, tensile strength is 270MPa, and tensile yield strength is 200MPa, unit elongation 40%;
Described high temperature plastic is deformed into extruding, and extrusion ratio is 80;
Heat-altered morphology alloy is carried out repeatedly normal temperature distortion-process annealing, each normal temperature distortion is divided into multi pass drawing, and the deflection of every time drawing is 8 ~ 20%, and the total deformation of each normal temperature distortion is 60 ~ 80%; Carry out a process annealing after each normal temperature distortion, intermediate anneal temperature is 150 ~ 300 DEG C, and the time is 10 ~ 20min; When the total deformation of repeatedly normal temperature distortion-process annealing reaches 95%, after process annealing, air cooling is to normal temperature the last time, and obtain medical bio degradable zinc alloy, tensile strength is 320MPa, and tensile yield strength is 240MPa, unit elongation 30%; Adopt weight-loss method, in 37 DEG C of SBF solution, record its erosion rate is 0.5mm/year.
Embodiment 4
Composition contains Mg 0.16%, Ag 0.43%, Ca 0.01%, Mn 0.05% by weight percentage, inevitable impurity≤0.2%, and surplus is Zn;
Metallic zinc, MAGNESIUM METAL, argent, calcium metal and manganese metal are as raw material; Pure metal zinc is heated to 520 ± 5 DEG C, after metallic zinc is dissolved, adds MAGNESIUM METAL, argent, calcium metal and manganese metal successively, after whole melting of metal, be stirred to and mix, obtain alloy melt;
Alloy melt is cooled to 460 ± 5 DEG C, utilizes graphite bell jar to be pressed into hexachloroethane in alloy melt, the hexachloroethane of press-in is 0.2% of alloy melt gross weight, then leaves standstill 15min 460 ± 5 DEG C of insulations;
Alloy melt is cooled to 440 ± 5 DEG C after leaving standstill and terminating and is poured in mould by insulation, and in casting cycle, die through water cooling, obtains ingot casting;
Ingot casting, at 300 DEG C ± 5 insulation 100min, be then warming up to 350 DEG C of insulations 4 hours, then water-cooled is to normal temperature, is obtained ingot blank;
By ingot blank at 150 DEG C of insulation 40min, then carry out high temperature plastic distortion at 150 DEG C, then air cooling is to normal temperature, obtain heat-altered morphology alloy, tensile strength is 220MPa, and tensile yield strength is 160MPa, unit elongation 30%;
Described high temperature plastic is deformed into rolling, and total deformation is 80%;
Heat-altered morphology alloy is carried out repeatedly normal temperature distortion-process annealing, each normal temperature distortion is divided into multi-pass rolling, and the deflection of every time rolling is 8 ~ 20%, and the total deformation of each normal temperature distortion is 60 ~ 80%; Carry out a process annealing after each normal temperature distortion, intermediate anneal temperature is 150 ~ 300 DEG C, and the time is 10 ~ 20min; When the total deformation of repeatedly normal temperature distortion-process annealing reaches 98%, after process annealing, air cooling is to normal temperature the last time, and obtain medical bio degradable zinc alloy, tensile strength is 270MPa, and tensile yield strength is 220MPa, unit elongation 22%; Adopt weight-loss method, in 37 DEG C of SBF solution, record its erosion rate is 0.8mm/year.
Embodiment 5
Composition contains Mg 0.47%, Ag 0.2%, Ca 0.38%, Mn 0.5% by weight percentage, inevitable impurity≤0.2%, and surplus is Zn;
Metallic zinc, MAGNESIUM METAL, argent, calcium metal and manganese metal are as raw material; Pure metal zinc is heated to 520 ± 5 DEG C, after metallic zinc is dissolved, adds MAGNESIUM METAL, argent, calcium metal and manganese metal successively, after whole melting of metal, be stirred to and mix, obtain alloy melt;
Alloy melt is cooled to 460 ± 5 DEG C, utilizes graphite bell jar to be pressed into hexachloroethane in alloy melt, the hexachloroethane of press-in is 0.3% of alloy melt gross weight, then leaves standstill 10min 460 ± 5 DEG C of insulations;
Alloy melt is cooled to 440 ± 5 DEG C after leaving standstill and terminating and is poured in mould by insulation, and in casting cycle, die through water cooling, obtains ingot casting;
Ingot casting, at 300 DEG C ± 5 insulation 200min, be then warming up to 330 DEG C of insulations 5 hours, then water-cooled is to normal temperature, is obtained ingot blank;
By ingot blank at 350 DEG C of insulation 20min, then carry out high temperature plastic distortion at 350 DEG C, then air cooling is to normal temperature, obtain heat-altered morphology alloy, tensile strength is 330MPa, and tensile yield strength is 270MPa, unit elongation 36%;
Described high temperature plastic is deformed into forging, and total deformation is 50%;
Heat-altered morphology alloy is carried out repeatedly normal temperature distortion-process annealing, each normal temperature distortion is divided into multi pass drawing, and the deflection of every time drawing is 8 ~ 20%, and the total deformation of each normal temperature distortion is 60 ~ 80%; Carry out a process annealing after each normal temperature distortion, intermediate anneal temperature is 150 DEG C, and the time is 20min; When the total deformation of repeatedly normal temperature distortion-process annealing reaches 96%, after process annealing, air cooling is to normal temperature the last time, and obtain medical bio degradable zinc alloy, tensile strength is 380MPa, and tensile yield strength is 300MPa, unit elongation 26%; Adopt weight-loss method, in 37 DEG C of SBF solution, record its erosion rate is 0.35mm/year.
Claims (5)
1. a medical bio degradable zinc alloy, it is characterized in that composition by weight percentage containing Mg 0.005 ~ 1%, Ag 0.01 ~ 0.5%, Ca 0.01 ~ 0.5%, Mn 0.01 ~ 0.5%, inevitable impurity≤0.2%, surplus is Zn.
2. a kind of medical bio degradable zinc alloy according to claim 1, it is characterized in that the tensile strength of this alloy is 260 ~ 450MPa, tensile yield strength is 195 ~ 380MPa, unit elongation 5 ~ 30%.
3. the preparation method of medical bio degradable zinc alloy according to claim 1, is characterized in that carrying out according to the following steps:
(1) metallic zinc, MAGNESIUM METAL, argent, calcium metal and manganese metal is prepared as raw material by composition according to claim 1; Pure metal zinc is heated to 520 ± 5 DEG C, after metallic zinc is dissolved, adds manganese metal, argent, calcium metal and MAGNESIUM METAL successively, after whole melting of metal, be stirred to and mix, obtain alloy melt;
(2) alloy melt is cooled to 460 ± 5 DEG C, utilizes graphite bell jar to be pressed into hexachloroethane in alloy melt, the hexachloroethane of press-in is 0.2 ~ 0.3% of alloy melt gross weight, then leaves standstill 10 ~ 20min 460 ± 5 DEG C of insulations;
(3) after the standing end of insulation, alloy melt being cooled to 440 ± 5 DEG C is poured in mould, and in casting cycle, die through water cooling, obtains ingot casting;
(4) ingot casting carries out Homogenization Treatments, and Homogenization Treatments is at 300 DEG C ± 5 insulation 100 ~ 200min; Then be warming up to 330 ~ 360 DEG C of insulations 3 ~ 5 hours, then water-cooled is to normal temperature, obtains ingot blank;
(5) ingot blank is incubated 20 ~ 40min at 150 ~ 350 DEG C, then carry out high temperature plastic distortion at 150 ~ 350 DEG C, then air cooling is to normal temperature, obtain heat-altered morphology alloy; Described high temperature plastic is deformed into extruding, rolling or forging, and when extruding, extrusion ratio is 16 ~ 150; When being rolled or forge, total deformation is 50 ~ 80%;
(6) heat-altered morphology alloy is carried out repeatedly normal temperature distortion-process annealing, each normal temperature distortion is divided into multi pass drawing or rolling, and the deflection of every time drawing or rolling is 8 ~ 20%, and the total deformation of each normal temperature distortion is 60 ~ 80%; Carry out a process annealing after each normal temperature distortion, intermediate anneal temperature is 150 ~ 300 DEG C, and the time is 10 ~ 20min; When the total deformation of repeatedly normal temperature distortion-process annealing reaches 92 ~ 98%, after process annealing, air cooling, to normal temperature, obtains medical bio degradable zinc alloy the last time.
4. the preparation method of medical bio degradable zinc alloy according to claim 3, it is characterized in that the tensile strength of described heat-altered morphology alloy is 220 ~ 400MPa, tensile yield strength is 160 ~ 360MPa, unit elongation 12 ~ 40%.
5. the preparation method of medical bio degradable zinc alloy according to claim 3, it is characterized in that described medical bio degradable zinc alloy adopts weight-loss method, in 37 DEG C of SBF solution, record its erosion rate is 0.2 ~ 0.8mm/year.
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