CN104046846A - Multilevel high-strength high-plasticity titanium-zirconium-based alloy and preparation method thereof - Google Patents
Multilevel high-strength high-plasticity titanium-zirconium-based alloy and preparation method thereof Download PDFInfo
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Abstract
The invention discloses multilevel high-strength high-plasticity titanium-zirconium-based alloy which is obtained from titanium-zirconium alloy with 38wt%-42wt% of Ti, 50wt%-54wt% of Zr, 5wt% of Al and 3wt% of V as a base body, consists of micron-sized primary alpha p large grains, sub-micron-sized alpha battens, nano-sized needle-like alpha' martensite and a residual beta base body, and has a multiphase multilevel structure. A preparation method of the alloy comprises the following steps: putting various raw materials into a non-consumable electro-arc furnace, and smelting to obtain an alloy ingot; coating the surface of the alloy ingot with a high-temperature antioxidant, heating in the furnace, preserving heat, cogging and forging to obtain plate-like alloy; heating and then cooling by water quenching; cutting the alloy plate into thin plates, and performing rolling deformation at room temperature; annealing in vacuum; performing two-step aging treatment. According to the alloy, the strength of the alloy is effectively improved while the plasticity of the alloy is kept.
Description
Technical field
The present invention relates to a kind of alloy material and preparation method, particularly titanium zirconium base alloy and preparation method.
Technical background
Titanium alloy has the good characteristics such as low density, high strength, good corrosion resistance, is the important structure material of aerospace flight vehicle.Now widely used Ti6Al4V titanium alloy, its tensile strength is 900～1100MPa, inefficacy unit elongation is 8～12%.TiZrAlV alloy is the novel alloy material growing up on the basis of Ti6Al4V alloy, and the introducing of zr element effectively raises intensity and the hardness of material, makes TiZrAlV alloy become a kind of candidate material of very potential aerospace flight vehicle.But the tensile strength of the TiZrAlV of report is only 1100～1292MPa at present, inefficacy unit elongation is 6.3～10%.Along with the development of aeronautical and space technology, the intensity of the titanium alloy material using in following aerospace field should >1500MPa.
Summary of the invention
The object of the present invention is to provide a kind of multilevel hierarchy high-strength high-plasticity titanium zirconium base alloy that can meet aerospace field aircraft development need and preparation method thereof.
A kind of multilevel hierarchy high-strength high-plasticity titanium zirconium base alloy of the present invention, it is the α being come into being by micron order obtaining as matrix taking mass percent as: the titanium zirconium base alloy of Ti38～42, Zr50～54, Al5, V3
plarge crystal grain, the α lath of submicron order, the α of nano level needle-like " the high-strength high-plasticity titanium zirconium base alloy with multilevel hierarchy that martensite and remaining β matrix form.
Preparation method of the present invention is mainly by Ti
xzr
92-xal
5v
3(wt%) alloy, combines with two step aging treatment process by room temperature rolling distortion, thermal annealing, obtains the titanium zirconium base alloy of a kind of high strength, high-ductility.
The preparation method of above-mentioned titanium zirconium base alloy is specific as follows:
1, the various raw materials such as titanium, zirconium, aluminium, vanadium are put into non-consumable arc furnace, smelting temperature >2000 DEG C, melting three times, each time is 10～50 minutes, obtains the uniform Ti of composition
xzr
92-xal
5v
3alloy cast ingot.
2, alloy cast ingot surface-coated high-temperature anti-oxidant step 1 being obtained, then in box type heater, be heated to 1025～1105 DEG C, be incubated and carry out cogging forging after 1～3 hour, after 2 upsetting pulls, use high-power milling train to be rolled it, deflection reaches more than 80%, finally obtains tabular alloy.Treat that tabular alloy is cooling, then carry out alloy surface finishing, remove surperficial antioxidant.
3, the tabular alloy of step 2 gained being removed to surperficial antioxidant is placed in resistance box heat treatment furnace and is heated to 850～870 DEG C, is incubated 1 hour, and then shrend is cooling.The object of this step process is by solid solution shrend, obtains more high temperature β phase, puies forward heavy alloyed deformation at room temperature ability.
4, utilize line to cut into the thin plate that thickness is 3～4mm step 3 gained alloy sheets, then carry out room temperature rolling distortion.Rolling strain rate is 1.5～2.2s
-1, preferably single pass volume under pressure is 1～2%, and total deformation is more than 90%, and overall strain amount is more than 2.66.
5, the alloy sheets of step 4 gained room temperature rolling distortion is placed in to high vacuum thermal annealing stove and carries out anneal, vacuum tightness is 10
-4～10
-5pa, temperature is 665-685 DEG C, after insulation 10min, air cooling is to room temperature; Then carry out two step ageing treatment, first at 625 DEG C of timeliness 1.5～2h, subsequently again at 300 DEG C of timeliness 1～4h air coolings to room temperature.
The present invention compared with prior art tool has the following advantages:
The present invention utilizes deformation at room temperature to regulate and control performance and the microstructure of alloy in conjunction with thermal annealing, but not the thermal distortion technology conventionally adopting.Compared with the single-stage lath structural titanium alloy obtaining with traditional thermal distortion technology, the present invention is owing to adopting deformation at room temperature to prepare the titanium-zirconium alloy with multilevel hierarchy in conjunction with thermal annealing.(tensile strength is 1100～1292MPa to the TiZrAlV alloy mechanical property obtaining with traditional thermal distortion technology, inefficacy unit elongation is 6.3～10%) compare, when the improved～200MPa of intensity of the TiZr base alloy that the present invention obtains, keep the quite inefficacy unit elongation of size.
The present invention, in keeping alloy plasticity, effectively raises the intensity of alloy, can meet following aerospace field for the intensity of 1500MPa grade high-strength titanium alloy and the requirement of plasticity.
The room temperature tensile test of the titanium-zirconium alloy that the present invention obtains is carried out on Instron5948 mechanical property testing system, and the mechanical property of the titanium-zirconium alloy that the present invention obtains is: tensile strength >=1500MPa, yield strength >=1400MPa, inefficacy unit elongation >=7%.
Brief description of the drawings
Fig. 1 is gained Ti in the embodiment of the present invention 1
40.2zr
51.8al
5v
3alloy transmission electron microscope photo figure.
Embodiment
Embodiment 1
The various raw materials such as titanium, zirconium, aluminium and vanadium are put into non-consumable arc furnace, smelting temperature >2000 DEG C, melting three times, each time is 45 minutes, obtains the uniform Ti of composition
40.2zr
51.8al
5v
3alloy cast ingot.By above-mentioned alloy cast ingot surface-coated high-temperature anti-oxidant, (titanium alloy high-temperature forges antioxidant protection coating; Shanghai Run Er metal surface material company limited produces); then in box type heater, be heated to 1000 DEG C; be incubated and carry out cogging forging after 2.5 hours; after 2 upsetting pulls; use high-power milling train to be rolled it, deflection reaches 80%, finally obtains tabular Ti
40.2zr
51.8al
5v
3alloy.Treat that alloy pig is cooling, then carry out alloy pig surfacing, remove surperficial antioxidant.The tabular alloy of removing surface anti-oxidant is placed in to resistance box heat treatment furnace and is heated to 865 DEG C, be incubated 1 hour, then use the cooling sample of shrend.Cooling shrend rear gained alloy sheets is utilized to line cutting sampling, and obtaining thickness is the thin plate after 4mm, then carries out room temperature rolling distortion.Rolling strain rate is 2.2s
-1, single pass volume under pressure is 2%, and total deformation is 90%, and overall strain amount is 2.66.Will be above gained room temperature rolling deforming alloy plate sample be placed in high vacuum thermal annealing stove (vacuum tightness be better than 10
-4pa) in, carry out anneal, temperature is 675 DEG C, is incubated 10 minutes, and then air cooling is to room temperature, 3 DEG C/min of rate of cooling.Afterwards annealing specimen is carried out to two step ageing treatment, first 625 DEG C of timeliness 2 hours, then 300 DEG C of timeliness after 1.5 hours air cooling to room temperature.
With JEOL2010 transmission electron microscope, the microstructure of sample is observed, pass through the prepared Ti of aforesaid method
40.2zr
51.1al
4.5v
4.2titanium zirconium base alloy be: the α being come into being by micron order
plarge crystal grain, the α lath of submicron order, the α of nano level needle-like " the heterogeneous multilevel hierarchy that martensite and remaining β matrix form.Room temperature tensile test is carried out on Instron5948 mechanical property testing system.The gauge length of stretching sample is of a size of length × wide × height=5 × 2 × 0.35mm
3, sample total length is 22mm, tensile strain rate is: 1 × 10
-3s
-1, in test process, utilize the length variations of Video Extensometer test specimens product gauge length.The mechanical property of sample is: tensile strength is 1550MPa, and yield strength is 1430MPa, and inefficacy unit elongation is 8.0%.
Embodiment 2
The various raw materials such as titanium, zirconium, aluminium and vanadium are put into non-consumable arc furnace, smelting temperature >2000 DEG C, melting three times, each time is 30 minutes, obtains the uniform Ti of composition
39.1zr
52.9al
5v
3alloy cast ingot.By above-mentioned alloy cast ingot surface-coated high-temperature anti-oxidant, (titanium alloy high-temperature forges antioxidant protection coating; Shanghai Run Er metal surface material company limited produces); then in box type heater, be heated to 1100 DEG C; be incubated and carry out cogging forging after 3 hours; after 2 upsetting pulls; use high-power milling train to be rolled it, deflection reaches 85%, finally obtains tabular Ti
39.1zr
52.9al
5v
3alloy.Treat that alloy pig is cooling, carrying out alloy pig surfacing, remove surperficial antioxidant.The tabular alloy of removing Surface Oxygen agent is placed in to resistance box heat treatment furnace and is heated to 850 DEG C, be incubated 1 hour, then use the cooling sample of shrend.Cooling shrend rear gained alloy sheets is utilized to line cutting sampling, and obtaining thickness is the thin plate after 3mm, then carries out room temperature rolling distortion.Rolling strain rate is 1.5s
-1, single pass volume under pressure is 1.5%, and total deformation is 93%, and overall strain amount is 3.1.Will be above gained room temperature rolling deforming alloy plate sample be placed in high vacuum thermal annealing stove (vacuum tightness be better than 10
-5pa) in, carry out anneal, temperature is 685 DEG C, is incubated 10 minutes.Then air cooling, to room temperature, carries out two step ageing treatment to annealing specimen afterwards, first 625 DEG C of timeliness 1.5 hours, then 300 DEG C of timeliness after 3 hours air cooling to room temperature.
The microstructure of sample is observed with JEOL2010 transmission electron microscope.Through the prepared Ti of aforesaid method
39.1zr
52.9al
5v
3titanium zirconium base alloy be: the α being come into being by micron order
plarge crystal grain, the α lath of submicron order, the α of nano level needle-like " the heterogeneous multilevel hierarchy that martensite and remaining β matrix form.Room temperature tensile test is carried out on Instron5948 mechanical property testing system.The gauge length of stretching sample is of a size of length × wide × height=5 × 2 × 0.35mm
3, sample total length is 22mm, tensile strain rate is: 1 × 10
-3s
-1, in test process, utilize the length variations of Video Extensometer test specimens product gauge length.The mechanical property of sample is: tensile strength is 1570MPa, and yield strength is 1440MPa, and inefficacy unit elongation is 7.0%.
Table 1 is this patent Ti
xzr
92-xal
5v
3with bibliographical information titanium alloy mechanical property contrast table
Note: documents source
1. Lee success, Fu Hengzhi, writes aerospace material, National Defense Industry Press, Beijing, 2002, p:41-56. in sticking up etc.
2. Liu is flat, Ma Mingzhen, Liang Shunxing, Jing Ran, Tan Chunlin, a kind of zirconium titanium base alloy and preparation method thereof, Chinese patent ZL201110159183.8.
Claims (3)
1. a multilevel hierarchy high-strength high-plasticity titanium zirconium base alloy, is characterized in that: it is the α being come into being by micron order obtaining as matrix taking mass percent as: the titanium zirconium base alloy of Ti38～42, Zr50～54, Al5, V3
plarge crystal grain, the α lath of submicron order, the α of nano level needle-like " the high-strength high-plasticity titanium zirconium base alloy with heterogeneous multilevel hierarchy that martensite and remaining β matrix form.
2. the preparation method of a kind of multilevel hierarchy high-strength high-plasticity titanium zirconium base alloy of claim 1, the mass percent of its titanium zirconium base alloy composition used is: Ti38～42, Zr50～54, Al5, V3, is characterized in that: its preparation method is as follows:
(1) titanium, zirconium, aluminium, the various raw materials of vanadium are put into non-consumable arc furnace, smelting temperature >2000 DEG C, melting three times, each time is 10-50 minute, obtains the uniform Ti of composition
xzr
92-xal
5v
3alloy cast ingot;
(2) alloy cast ingot surface-coated high-temperature anti-oxidant step 1 being obtained, then in box type heater, be heated to 1025～1105 DEG C, be incubated and carry out cogging forging after 1～3 hour, after 2 upsetting pulls, use high-power milling train to be rolled it, deflection reaches more than 80%, finally obtain tabular alloy, treat that tabular alloy is cooling, then carry out alloy surface finishing, remove surperficial antioxidant;
(3) the tabular alloy of step 2 gained being removed to surperficial antioxidant is placed in resistance box heat treatment furnace and is heated to 850～870 DEG C, is incubated 1 hour, and then shrend is cooling;
(4) utilize line to cut into the thin plate that thickness is 3～4mm step 3 gained alloy sheets, then carry out room temperature rolling distortion, rolling strain rate is 1.5～2.2s
-1, total deformation is more than 90%, overall strain amount is more than 2.66;
(5) alloy sheets of step 4 gained room temperature rolling distortion is placed in to high vacuum thermal annealing stove and carries out anneal, vacuum tightness is 10
-4～10
-5pa, temperature is 665-685 DEG C, is incubated after 10 minutes air cooling to room temperature; Then annealing specimen is carried out to two step ageing treatment, first at 625 DEG C of timeliness 1.5～2h, subsequently again at 300 DEG C of timeliness 1～4h air coolings to room temperature.
3. the preparation method of a kind of multilevel hierarchy high-strength high-plasticity titanium zirconium base alloy according to claim 2, is characterized in that: room temperature rolling distortion single pass volume under pressure is 1～2%.
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105238955A (en) * | 2015-10-22 | 2016-01-13 | 燕山大学 | High-ductility zirconium alloy and preparation method thereof |
| CN106498138A (en) * | 2016-10-20 | 2017-03-15 | 西安交通大学 | A kind of multiphase nano lamellar alloy material and preparation method thereof |
| CN107385371A (en) * | 2017-08-08 | 2017-11-24 | 西北有色金属研究院 | The processing method for obtaining the metastable beta titanium alloy of corynebacterium primary alpha phase tissue |
| CN109877181A (en) * | 2019-04-17 | 2019-06-14 | 广西南南铝加工有限公司 | A kind of preparation method of high uniformity aluminum alloy plate materials |
| CN112941368A (en) * | 2021-01-29 | 2021-06-11 | 散裂中子源科学中心 | Titanium-zirconium alloy and preparation method and application thereof |
| CN113088760A (en) * | 2021-04-02 | 2021-07-09 | 河北工程大学 | Low-modulus high-strength biomedical titanium-zirconium-based alloy and preparation method thereof |
| CN113549788A (en) * | 2021-07-28 | 2021-10-26 | 燕山大学 | Double-state high-strength plastic-zirconium alloy and preparation method thereof |
| CN113981347A (en) * | 2021-09-29 | 2022-01-28 | 西安交通大学 | High-strength-plasticity heterostructure zirconium alloy and preparation method thereof |
| CN116145065A (en) * | 2023-02-27 | 2023-05-23 | 沈阳工业大学 | Multistage heat treatment method for improving vickers hardness of TC4 titanium alloy additive components |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009263797A (en) * | 1999-04-30 | 2009-11-12 | California Inst Of Technology | Composite amorphous metal object, and method for producing the same |
| CN102260805A (en) * | 2011-06-15 | 2011-11-30 | 燕山大学 | Zirconium titanium based alloy and preparation method thereof |
| CN103602840A (en) * | 2013-11-05 | 2014-02-26 | 燕山大学 | Preparation method of titanium zirconium base alloy |
-
2014
- 2014-07-02 CN CN201410312161.4A patent/CN104046846A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009263797A (en) * | 1999-04-30 | 2009-11-12 | California Inst Of Technology | Composite amorphous metal object, and method for producing the same |
| CN102260805A (en) * | 2011-06-15 | 2011-11-30 | 燕山大学 | Zirconium titanium based alloy and preparation method thereof |
| CN103602840A (en) * | 2013-11-05 | 2014-02-26 | 燕山大学 | Preparation method of titanium zirconium base alloy |
Non-Patent Citations (1)
| Title |
|---|
| MING LI ET AL.: "Simultaneously enhancing fracture toughness and strength in a hierarchical nanolamella-structured alloy", 《MATERIALSSCIENCE & ENGINEERING A》, vol. 612, 17 June 2014 (2014-06-17), XP029036722, DOI: doi:10.1016/j.msea.2014.06.026 * |
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| CN105238955A (en) * | 2015-10-22 | 2016-01-13 | 燕山大学 | High-ductility zirconium alloy and preparation method thereof |
| CN106498138A (en) * | 2016-10-20 | 2017-03-15 | 西安交通大学 | A kind of multiphase nano lamellar alloy material and preparation method thereof |
| CN107385371A (en) * | 2017-08-08 | 2017-11-24 | 西北有色金属研究院 | The processing method for obtaining the metastable beta titanium alloy of corynebacterium primary alpha phase tissue |
| CN107385371B (en) * | 2017-08-08 | 2019-03-19 | 西北有色金属研究院 | The processing method for obtaining the metastable beta titanium alloy of corynebacterium primary alpha phase tissue |
| CN109877181A (en) * | 2019-04-17 | 2019-06-14 | 广西南南铝加工有限公司 | A kind of preparation method of high uniformity aluminum alloy plate materials |
| CN112941368A (en) * | 2021-01-29 | 2021-06-11 | 散裂中子源科学中心 | Titanium-zirconium alloy and preparation method and application thereof |
| CN113088760A (en) * | 2021-04-02 | 2021-07-09 | 河北工程大学 | Low-modulus high-strength biomedical titanium-zirconium-based alloy and preparation method thereof |
| CN113549788A (en) * | 2021-07-28 | 2021-10-26 | 燕山大学 | Double-state high-strength plastic-zirconium alloy and preparation method thereof |
| CN113981347A (en) * | 2021-09-29 | 2022-01-28 | 西安交通大学 | High-strength-plasticity heterostructure zirconium alloy and preparation method thereof |
| CN116145065A (en) * | 2023-02-27 | 2023-05-23 | 沈阳工业大学 | Multistage heat treatment method for improving vickers hardness of TC4 titanium alloy additive components |
| CN116145065B (en) * | 2023-02-27 | 2024-06-11 | 沈阳工业大学 | Multistage heat treatment method for improving vickers hardness of TC4 titanium alloy additive components |
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Application publication date: 20140917 |