Summary of the invention
The objective of the invention is provides a kind of snappiness (the minimum 37.6GPa of reaching of Young's modulus), a kind of intravascular stent beta titanium alloy that intensity is moderate, working plasticity is better, cost is relatively low at the deficiency of above-mentioned prior art in solution stent postoperative thrombosis and the existence of restenosis problem.
Method of the present invention is achieved through the following technical solutions.
A kind of intravascular stent beta titanium alloy is characterized in that the weight percent of its alloy consists of: zirconium 0.5%-9.5%, and molybdenum 0.5%-6.5%, niobium 8.5%-28.5%, surplus is titanium and unavoidable impurities, wherein low gap constituent content carbon≤0.03%; Nitrogen≤0.04%, hydrogen≤0.003%, oxygen≤0.12%.
A kind of intravascular stent beta titanium alloy is characterized in that the weight percent of alloy consists of: zirconium 3%-6%, and molybdenum 2%-6%, niobium 13%-16% or 24%-27%, surplus is titanium and unavoidable impurities.The molybdenum equivalent is 9.9-10.2.
Intravascular stent beta titanium alloy of the present invention adopts a certain proportion of, as to have good biocompatibility zirconium Zr, molybdenum Mo, niobium Nb element as additive, and the molybdenum equivalent of control alloy is 9.9-10.2, makes it form the stable nearly β type medical titanium alloy that is situated between.The normal calculation formula of relevant molybdenum is as follows:
〔Mo〕eq=%〔Mo〕+%〔V/1.5〕+〔W〕/2+%〔Nb〕/3.6+%〔Ta〕/4.5+%〔Fe〕/0.35+%〔Cr〕/0.63+%〔Mn〕/0.65+%〔Ni〕/0.8-%〔Al〕
The aforementioned calculation reason is that Mo, Nb, Zr element are beneficial to alloy strengthening; Nb, Zr, Mo element are beneficial to and reduce the alloy Young's modulus; Zr, Sn, Nb element are little to the alloy plasticity disadvantageous effect, even improve alloy plasticity; The Mo crystal grain thinning can improve the hot and cold formability of alloy; Nb is also favourable to improving toughness.But Mo, Nb element add-on are too much, increase the stable degree of alloy first, the solid solution aging effect of alloy is weakened or lose and can't realize alloy structure and performance adjustment; Second increase alloy density and raw material and melting tooling cost thereof, and be prone to the composition segregation during melting and tissue odds is even.For example United States Patent (USP) (US5,871,595) has reported that new Ti-Zr-Mo-Nb is a biological titanium alloy, and its alloy content is very high, and the weight ratio of its component is Ti-Zr (10%-46%)-Mo (3%-15%)-Nb (29%-70%).And Mo, No, the Zr element of control suitable proportion make it form the stable nearly beta titanium alloy that is situated between, thereby can handle by solid solution aging, adjust alloy property (as intensity, Young's modulus and unit elongation etc.) significantly; And this type of alloy easily brings out martensite and forms (this and 316L type stainless steel and Ti-Ni marmem are similar a bit) in solution treatment or when loading, and then causes the higher plasticity of alloy, is convenient to following process, as the cold reduction of tubes and kapillary drawing.
Alloy of the present invention, refractory metal elements Mo, Nb can master alloy TiNb (the Nb weight content is 25%-55%) and TiMo (Mo weight content 10%-30%) form add, also can the Nb bar and the Mo powder add; Element Zr adds with zirconium sponge or pure zirconium strips; Adopt the zero level titanium sponge with lower interstitial impurity constituent content in the control alloy substrate.
Alloy of the present invention can be in vacuum consumable electrode arc furnace twice or three times of melting.The ingot casting cogging is forged and to be chosen in 1000 ℃~1100 ℃ and to carry out, and selects 900 ℃~1000 ℃ to implement finished products forging or rolling etc.The solution treatment system is: temperature is controlled between-50 ℃~+ 100 ℃ of α/β transformation temperature, and soaking time 0.5~1.5 hour adopts shrend or air cooling; System of ageing treatment is: temperature is chosen in 480 ℃~640 ℃, is incubated 4~12 hours, air cooling.The performance data of its tensile strength, yield strength, unit elongation, reduction of area and Young's modulus and over-all properties all are better than traditional in the world 316L type medical stainless steel and Ti-Ni marmem at present.
Alloy of the present invention has moderate intensity, lower bullet modulus, higher plasticity and relatively low cost, and its over-all properties is handled the adjustment that can realize in a big way by solid solution aging.Therefore, alloy of the present invention can be used for human body cardiovascular and cerebrovascular diseases and other medical intestines, gas, gland (reaching the narrow venereal disease change of body cavity as esophagus cancer, prostatomegaly, larynx tracheostenosis etc. as all kinds of peripheral vascular diseases such as atherosclerosis obliterans, vasculitis etc.) treatment of diseases, is a kind of preparation intravascular stent and other tubular medical support ideal equivalent material.Also can be used for other surgery implantation piece material.
Embodiment
With the zirconium sponge of the master alloy TiNb (Nb weight content 25%-55%) of refractory metal elements Mo, Nb and TiMo (Mo weight content 10%-30%) or Nb bar and Mo powder, element Zr or pure zirconium bar, zero level titanium sponge, melting is twice or three times in vacuum consumable electrode arc furnace, the preparation alloy pig, its weight percent consists of: zirconium 0.5%-9.5%, molybdenum 0.5%-6.5%, niobium 8.5%-28.5%, surplus is titanium and unavoidable impurities, wherein low gap constituent content carbon≤0.03%; Nitrogen≤0.04%, hydrogen≤0.003%, oxygen≤0.12%.And the weight percent of the best composition of alloy consists of zirconium 3%-6%, molybdenum 2%-6%, and niobium 13%-16% or 24%-27%, surplus is titanium and unavoidable impurities.Its best molybdenum equivalent is 9.9-10.2.Ingot casting cogging forging is chosen in 1000 ℃~1100 ℃ to be carried out, and selects 900 ℃~1000 ℃ to implement finished products forging or rolling.The solution treatment system is: temperature is controlled between-50 ℃~+ 100 ℃ of α/β transformation temperature, and soaking time 0.5~1.5 hour adopts shrend or air cooling; System of ageing treatment is: temperature is chosen in 480 ℃~640 ℃, is incubated 4~12 hours, makes alloy of the present invention after the timeliness thermal treatment of air cooling.
Embodiment 1
Adopting 0 grade of titanium sponge, nuclear power zirconium sponge and Ti-15Mo and Ti-52Nb master alloy is raw material, carries out twice melting after batch mixing is pressed into electrode in vacuum consumable electrode arc furnace, 32 volts of melting once voltages, melting electric current 1300 peaces; 35 volts of secondary smelting voltages, melting electric current 2200 peaces; Melting initial vacuum degree is not less than 10
-2Handkerchief.Secondary alloy ingot weight percent consists of: zirconium 5%; Molybdenum 3%, niobium 25%; Surplus is Ti, and the molybdenum equivalent is 9.9.Ingot casting carries out cogging and forges under 1050 ℃, after upsetting pull repeatedly, be swaged into a mouthful 42mm square rod earlier, is swaged into φ 37mm pole again.Then 950 ℃ down through continuous passage hot rollings, (its original state property can be σ to make the thin rod of φ 12.5mm
b=760MPa; σ
0.2=730MPa; δ
s=19%; ψ=83.5%; E=67.4GPa).At last according to service requirements, carry out the solution treatment of 680 ℃ of insulations 1 hour, air cooling after, make alloy of the present invention.Recording alloy at room temperature tensile property parameter is:
σ
b=665MPa;σ
0.2=680MPa;δ
s=38%;ψ=79%;E=66.1GPa。
Embodiment 2
Other condition is with embodiment 1, and the alloy pig weight percent consists of: zirconium 5.5%; Molybdenum 3%, niobium 25%; Surplus is Ti, and the molybdenum equivalent is 9.9.Ingot casting carries out cogging and forges under 1000 ℃, then 900 ℃ of continuous passage hot rollings of process down, make the thin rod of φ 12.5mm.Carry out the solution treatment of 750 ℃ of insulations 1 hour, air cooling, make alloy of the present invention.The performance perameter that records alloy is:
σ
b=665MPa;σ
0.2=645MPa;δ
s=40%;ψ=81%;E=68.5GPa。
Embodiment 3
Other condition is with embodiment 1, and the alloy pig weight percent consists of: zirconium 6%; Molybdenum 3%, niobium 25%, surplus is Ti, the molybdenum equivalent is 9.9.Ingot casting carries out cogging and forges under 1100 ℃, then 900 ℃ of continuous passage hot rollings of process down, make the thin rod of φ 12.5mm.Carry out the solution treatment of 820 ℃ of insulations 1 hour, air cooling, make alloy of the present invention.The performance perameter that records alloy is:
σ
b=640MPa;σ
0.2=570MPa;δ
s=45%;ψ=80.5%;E=72.4GPa。
Embodiment 4
Other condition is with embodiment 1, and the alloy pig weight percent consists of: zirconium 4.5%; Molybdenum 3%, niobium 25%, surplus is Ti, the molybdenum equivalent is 9.9.Ingot casting carries out cogging and forges under 1050 ℃, then 900 ℃ of continuous passage hot rollings of process down, make the thin rod of φ 12.5mm.After carrying out the timeliness thermal treatment of 680 ℃/1 hour, the solution treatment of air cooling and 510 ℃/6 hours, air cooling, make alloy of the present invention.The performance perameter that records alloy is:
σ
b=935MPa;σ
0.2=890MPa;δ
s=20%;E=82.4GPa。
Embodiment 5
Other condition is with embodiment 1, and the alloy pig weight percent consists of: zirconium 4%; Molybdenum 3.5%, niobium 25%; Surplus is Ti, and the molybdenum equivalent is 10.4.Ingot casting carries out cogging and forges under 1100 ℃, then 950 ℃ of continuous passage hot rollings of process down, make the thin rod of φ 12.5mm.After carrying out the timeliness thermal treatment of 680 ℃/1 hour, the solution treatment of air cooling and 650 ℃/6 hours, air cooling, make alloy finished product of the present invention.The performance perameter that records alloy is:
σ
b=785MPa;σ
0.2=745MPa;δ
s=23%;E=76.2GPa。
Embodiment 6
Other condition is with embodiment 1, and the alloy pig weight percent consists of: zirconium 3.5%; Molybdenum 2.5%, niobium 25%; Surplus is Ti, and the molybdenum equivalent is 9.4.Ingot casting carries out cogging and forges under 1000 ℃, then 950 ℃ of continuous passage hot rollings of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 680 ℃/1 hour, the solution treatment of air cooling and 610 ℃/6 hours, air cooling after, make alloy finished product of the present invention.The performance perameter that records alloy is:
σ
b=705MPa;σ
0.2=660MPa;δ
s=19%;;E=65.6GPa。
Embodiment 7
Other condition is with embodiment 1, and the alloy pig weight percent consists of: zirconium 3%; Molybdenum 4%, niobium 25%; Surplus is Ti, and the molybdenum equivalent is 10.9.Ingot casting carries out cogging and forges under 1100 ℃, then 900 ℃ of continuous passage hot rollings of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 750 ℃/1 hour, the solution treatment of air cooling and 510 ℃/6 hours, air cooling after, make alloy finished product of the present invention.The performance perameter that records alloy is:
σ
b=850MPa;σ
0.2=770MPa;δ
s=22.5%;;E=83.7GPa。
Embodiment 8
Other condition is with embodiment 1, and the alloy pig weight percent consists of: zirconium 2.5%; Molybdenum 2%, niobium 25%; Surplus is Ti, and the molybdenum equivalent is 8.9.Ingot casting carries out cogging and forges under 1000 ℃, then 900 ℃ of continuous passage hot rollings of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 750 ℃/1 hour, the solution treatment of air cooling and 560 ℃/6 hours, air cooling after, make alloy finished product of the present invention.The performance perameter that records alloy is:
σ
b=690MPa;σ
0.2=640MPa;δ
s=23%;;E=70.7GPa。
Embodiment 9
Other condition is with embodiment 1, and the alloy pig weight percent consists of: zirconium Zr2%; Molybdenum Mo3%, niobium Nb25.5%; Surplus is Ti, and molybdenum Mo equivalent is 10.1.Ingot casting carries out cogging and forges under 1050 ℃, then 900 ℃ of continuous passage hot rollings of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 750 ℃/1 hour, the solution treatment of air cooling and 610 ℃/6 hours, air cooling after, make alloy finished product of the present invention.The performance perameter that records alloy is:
σ
b=655MPa;σ
0.2=620MPa;δ
s=31%;;E=72.1GPa。
Embodiment 10
Other condition is with embodiment 1, and the alloy pig weight percent consists of: zirconium Zr5%; Molybdenum Mo3%, niobium Nb26%; Surplus is Ti, and molybdenum Mo equivalent is 10.2.Ingot casting carries out cogging and forges under 1050 ℃, then 900 ℃ of continuous passage hot rollings of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 820 ℃/1 hour, the solution treatment of air cooling and 510 ℃/6 hours, air cooling after, make alloy finished product of the present invention.The performance perameter that records alloy is:
σ
b=785MPa;σ
0.2=71?0MPa;δ
s=21.5%;;E=79.4GPa。
Embodiment 11
Other condition is with embodiment 1, and the alloy pig weight percent consists of: zirconium Zr5%; Molybdenum Mo3%, niobium Nb24.5%; Surplus is Ti, and molybdenum Mo equivalent is 9.8.Ingot casting carries out cogging and forges under 1000 ℃, then 900 ℃ of continuous passage hot rollings of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 820 ℃/1 hour, the solution treatment of air cooling and 560 ℃/6 hours, air cooling after, make alloy finished product of the present invention.The performance perameter that records alloy is:
σ
b=680MPa;σ
0.2=630MPa;δ
s=23%;;E=72.6GPa。
Embodiment 12
Other condition is with embodiment 1, and the alloy pig weight percent consists of: zirconium Zr5%; Molybdenum Mo3%, niobium Nb24%; Surplus is Ti, and molybdenum Mo equivalent is 9.7.Ingot casting carries out cogging and forges under 1000 ℃, then 950 ℃ of continuous passage hot rollings of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 820 ℃/1 hour, the solution treatment of air cooling and 610 ℃/6 hours, air cooling after, make alloy finished product of the present invention.The performance perameter that records alloy is:
σ
b=640MPa;σ
0.2=580MPa;δ
s=39%;;E=75.7GPa。
Embodiment 13
Adopting 0 grade of titanium sponge Ti, pure zirconium Zr bar and pure Mo powder and pure Nb is raw material, after batch mixing is pressed into electrode, carries out twice melting in vacuum consumable electrode arc furnace.32 volts of melting once voltages, melting electric current 1300 peaces; 32 volts of secondary smelting voltages, melting electric current 2200 peaces; Melting initial vacuum degree is not less than 10
-2Handkerchief.Making alloy cast ingot is φ 90 * 280mm.The weight percent of alloy pig consists of: zirconium 5%; Molybdenum 6%, niobium 15%; Surplus is Ti, and the molybdenum equivalent is 10.2.Ingot casting carries out cogging and forges under 1050 ℃, after upsetting pull repeatedly, be swaged into a mouthful 42mm square rod earlier, is swaged into φ 37mm pole again.Then 950 ℃ down through continuous passage hot-swages, (its original state property can be σ to make the thin rod of φ 12.5mm
b=770MPa; σ
0.2=315MPa; δ
s=23%; ψ=75%; E=53.2GPa).At last according to service requirements, carry out 750 ℃/1 hour, the solution treatment of air cooling, make alloy of the present invention.The performance perameter that records alloy is:
σ
b=695MPa;σ
0.2=320MPa;δ
s=24%;ψ=84%;E=53.8GPa。
Embodiment 14
Other condition is with embodiment 13, and the weight percent of alloy pig consists of: zirconium 5.5%; Molybdenum 6%, niobium 15%; Surplus is Ti, and the molybdenum equivalent is 10.2.Ingot casting carries out cogging and forges under 1050 ℃, then 900 ℃ down through continuous passage hot-swages, make the thin rod of φ 12.5mm, carry out 820 ℃/1 hour, the solution treatment of air cooling, make alloy of the present invention.The performance perameter that records alloy is:
σ
b=665MPa;σ
0.2=275MPa;δ
s=26%;ψ=79%;E=52.6GPa。
Embodiment 15
Other condition is with embodiment 13, and the weight percent of alloy pig consists of: zirconium 6%; Molybdenum 6%, niobium 15%; Surplus is Ti, and the molybdenum equivalent is 10.2.Ingot casting carries out cogging and forges under 1100 ℃, then 900 ℃ down through continuous passage hot-swages, make the thin rod of φ 12.5mm, carry out 680 ℃/1 hour, the solution treatment of air cooling, make alloy of the present invention.The performance perameter that records alloy is:
σ
b=740MPa;σ
0.2=275MPa;δ
s=26%;ψ=75%;E=56.4GPa。
Embodiment 16
Other condition is with embodiment 13, and the weight percent of alloy pig consists of: zirconium 4.5%; Molybdenum 6%, niobium 15%; Surplus is Ti, and the molybdenum equivalent is 10.2.Ingot casting carries out cogging and forges under 1000 ℃, then 900 ℃ of continuous passage hot-swages of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 680 ℃/1 hour, the solution treatment of air cooling and 510 ℃/6 hours, air cooling after, make alloy of the present invention.The performance perameter that records alloy is:
σ
b=950MPa;σ
0.2=905MPa;δ
s=20%;E=78.1GPa。
Embodiment 17
Other condition is with embodiment 13, and the weight percent of alloy pig consists of: zirconium 4%; Molybdenum 6%, niobium 15%; Surplus is Ti, and the molybdenum equivalent is 10.2.Ingot casting carries out cogging and forges under 1050 ℃, then 950 ℃ of continuous passage hot-swages of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 680 ℃/1 hour, the solution treatment of air cooling and 560 ℃/6 hours, air cooling after, make alloy of the present invention.The performance perameter that records alloy is:
σ
b=790MPa;σ
0.2=750MPa;δ
s=22%;E=74GPa。
Embodiment 18
Other condition is with embodiment 13, and the weight percent of alloy pig consists of: zirconium 3.5%; Molybdenum 5%, niobium 25%; Surplus is Ti, and the molybdenum equivalent is 8.9.Ingot casting carries out cogging and forges under 1100 ℃, then 950 ℃ of continuous passage hot-swages of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 680 ℃/1 hour, the solution treatment of air cooling and 610 ℃/6 hours, air cooling after, make alloy of the present invention.The performance perameter that records alloy is:
σ
b=695MPa;σ
0.2=610MPa;δ
s=23.1%;E=62.9GPa。
Embodiment 19
Other condition is with embodiment 13, and the weight percent of alloy pig consists of: zirconium 3%; Molybdenum 5%, niobium 15%; Surplus is Ti, and the molybdenum equivalent is 8.9.Ingot casting carries out cogging and forges under 1050 ℃, then 900 ℃ of continuous passage hot-swages of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 750 ℃/1 hour, the solution treatment of air cooling and 510 ℃/6 hours, air cooling after, make alloy of the present invention.The performance perameter that records alloy is:
σ
b=805MPa;σ
0.2=6555MPa;δ
s=20%;E=67.3GPa。
Embodiment 20
Other condition is with embodiment 13, and the weight percent of alloy pig consists of: zirconium 2.5%; Molybdenum 5%, niobium 15%; Surplus is Ti, and the molybdenum equivalent is 8.9.Ingot casting carries out cogging and forges under 1100 ℃, then 950 ℃ of continuous passage hot-swages of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 750 ℃/1 hour, the solution treatment of air cooling and 560 ℃/6 hours, air cooling after, make alloy of the present invention.The performance perameter that records alloy is:
σ
b=695MPa;σ
0.2=340MPa;δ
s=22.4%;E=62.2GPa。
Embodiment 21
Other condition is with embodiment 13, and the weight percent of alloy pig consists of: zirconium 2%; Molybdenum 4%, niobium 15%; Surplus is Ti, and the molybdenum equivalent is 7.9.Ingot casting carries out cogging and forges under 1000 ℃, then 900 ℃ of continuous passage hot-swages of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 750 ℃/1 hour, the solution treatment of air cooling and 610 ℃/6 hours, air cooling after, make alloy of the present invention.The performance perameter that records alloy is:
σ
b=690MPa;σ
0.2=295MPa;δ
s=24%;E=37.6GPa。
Embodiment 22
Other condition is with embodiment 13, and the weight percent of alloy pig consists of: zirconium 5%; Molybdenum 6%, niobium 16%; Surplus is Ti, and the molybdenum equivalent is 10.2.Ingot casting carries out cogging and forges under 1000 ℃, then 900 ℃ of continuous passage hot-swages of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 820 ℃/1 hour, the solution treatment of air cooling and 510 ℃/6 hours, air cooling after, make alloy of the present invention.The performance perameter that records alloy is:
σ
b=805MPa;σ
0.2=650MPa;δ
s=19%;E=68.1GPa。
Embodiment 23
Other condition is with embodiment 13, and the weight percent of alloy pig consists of: zirconium 5%; Molybdenum 6%, niobium 14%; Surplus is Ti, and the molybdenum equivalent is 9.9.Ingot casting carries out cogging and forges under 1050 ℃, then 900 ℃ of continuous passage hot-swages of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 820 ℃/1 hour, the solution treatment of air cooling and 560 ℃/6 hours, air cooling after, make alloy of the present invention.The performance perameter that records alloy is:
σ
b=695MPa;σ
0.2=320MPa;δ
s=23%;E=43.4GPa。
Embodiment 24
Other condition is with embodiment 13, and the weight percent of alloy pig consists of: zirconium 5%; Molybdenum 5%, niobium 15.5%; Surplus is Ti, and the molybdenum equivalent is 9.3.Ingot casting carries out cogging and forges under 1000 ℃, then 950 ℃ of continuous passage hot-swages of process down, make the thin rod of φ 12.5mm, carry out the timeliness thermal treatment of 820 ℃/1 hour, the solution treatment of air cooling and 610 ℃/6 hours, air cooling after, make alloy of the present invention.The performance perameter that records alloy is:
σ
b=690MPa;σ
0.2=335MPa;δ
s=23%;E=62GPa。