Ti based cast alloy

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy, in particular to welded Ti based cast alloys, and intended for manufacturing of the shaped castings of valves, pumps, bodies used in shipbuilding, chemical and other industries. Ti based alloy contains in wt %: 3.0-4.5 Al, 0.02-0.14 C, 0.05-0.14 O, 0.02-0.25 Fe, 0.02-0.12 Si, 0,02-0,15 W, 0.001-0.005 B, Ti and admixtures - rest. Ratios are met: C+O2 ≤ 0.20, 2(V+Fe+Si)/Al ≤ 0.20.

EFFECT: alloy is workable, has good cast properties and set of mechanical properties ensuring operation reliability.

2 tbl, 1 ex

 

The invention relates to ferrous metallurgy, in particular to the metallurgy of the welded cast alloys based on titanium, and is intended for the manufacture of shaped castings of valves, pumps, casings, etc., used in shipbuilding, chemical and other industries.

Known welded cast alloys based on titanium: alloy brand VTL, alloy brand VT6L [S. G. Glazunov, A. A. Neustroev. Production of shaped castings of titanium alloys. M.: metallurgy, 1998, p. 17].

The disadvantages of the alloy grade VTL is the reduced strength of the alloy grade VT6L, the lack of ductility and poor occupancy of small channels molds. The occupancy rate is the capacity of the metal in the interaction with metal forms or shapes of compacted graphite to fill the walls of castings up to 5 mm. the Occupancy rate is one of the main criteria when selecting an alloy for the manufacture of castings.

The closest in content ingredients is a weldable alloy brand VTL, taken as a prototype, containing aluminum 4,1-6,2, carbon up to 0.20, oxygen to 0.20, hydrogen 0.015%, iron up to 0.35%, silicon up to 0.20% zirconium, 0.80%, tungsten up to 0.20% [S. G. Glazunov, A. A. Neustroev. Production of shaped castings of titanium alloys. M.: metallurgy, 1998, p. 17].

This alloy has the following disadvantages:

<> bad the occupancy of small cross-sections of molds (filled with liquid metal of the section of castings is more than 10 mm) and low values of ductility (δ less than 5%).

When the content of carbon (0,20%), iron (0,35%), oxygen (0,20%), silicon (0,20%), tungsten (0,20%) the occupancy rate of the small channels of molds is reduced (flooded sections of walls or channels more than 20 mm), the ductility of the alloy decreases to 2%.

The occupancy of small cross-sections of molds for titanium alloy depends on the temperature interval of crystallization: the longer the interval of crystallization, the worse the occupancy of molds. The interval of crystallization, in turn, depends on the content in the alloy β-stabilizing elements, such as iron, tungsten, silicon. At an iron content of 0.35%, tungsten 0.20% and silicon 0,20% interval of crystallization is increased by 15-20°, the occupancy of the mold is reduced in 2-3 times.

The technical result of the invention is the creation of a cast alloy with good casting properties, in particular, increased occupancy of small channels molds (cross-sections from 2.5 to 10 mm), high plasticity while maintaining good welding properties.

The technical result is achieved as a result of complex microalloying α-stabilizing elements (aluminum, oxygen, carbon) with a small amount� β-stabilizing elements low concentrations (iron, silicon and additionally introduced vanadium and boron).

The technical result is achieved due to the fact that in the known composition of the alloy containing aluminum, carbon, oxygen, iron, silicon, optionally enter the vanadium and boron in the following ratio of components (wt.%):

aluminum3,0-4,5
carbon0,02-0,14
oxygen0,05-0,14
iron0,02-0,25
silicon0,02-0,12
vanadium0,02-0,15
Borof 0.001-0.005
titanium and inevitable impuritiesthe rest,

and the following conditions are met:

(C+O2)≤0,20;

2(V+Fe+Si)/Al≤0,20.

Boron in the range of 0.001-0.005% is introduced into the melt as a modifier for the structure refinement of the alloy, which provides good casting and welding properties. Increasing boron content above 0.005 per cent leads to the formation of borides of titanium, which are sources of micro-cracks and reduce the occupancy of small sections of litein�x forms and ductility. With the introduction of boron less than 0.001%, the effect of the modification and the structure refinement was observed.

The combination of aluminum and small amounts of β-stabilizing elements low concentration (silicon, iron, vanadium) provides complex microalloying by grinding the microstructure and increases the occupancy of small channels molds and the ductility of the alloy.

Aluminum in the range from 3.0 to 4.5% increases the occupancy of the small channels of the mold by reducing the viscosity of the liquid metal.

The iron content (0.25%) reduced compared to the known alloy to ensure the occupancy of the small channels of the mold.

The silicon content (0.12%) decreased compared to the alloy of the prototype, since the silicon content more than 0.12% formed silicides of titanium, reducing the occupancy of the small channels of the mold.

The oxygen content in the claimed range (0,05-0,14%) and carbon (0,02-0,14%) provides ductility and welding properties of the alloy. The excess of (C+O2)>0,20% will reduce the characteristics of plasticity, welding properties of the alloy.

Attitude 2(V+Fe+Si)/Al≤0,20 provides the occupancy of the small channels of the mold. When the ratio is 2(V+Fe+Si)/Al>0.20 occupancy of the small channels of the mold is reduced.

A sample process

Formulations of the proposed and known alloys in�pluviale in vacuum arc garnissage melting and casting furnace "Neva-2". Of the proposed and known alloys were casted castings type "plate" of 20×300×400 mm. for the study of the mechanical properties. The casting of the metal was produced in metallic form. Then of metal castings produced samples for tensile tests according to GOST 1497-84 and plates for welding of 20×50×100, which is welded between a TIG. To assess the quality of weld joint from the weld zone produced samples to determine the total work of fracture of the specimen with the initial crack of impact bending ATu.

The chemical compositions of the proposed alloy and alloy prototype are shown in table 1.

The occupancy of the small channels of the mold was studied in filling the proposed alloy and alloy prototype cylindrical samples with a diameter from 2.5 to 10 mm and 200 mm long, located vertically in the metallic form.

Results characterization of plasticity, of fracture of the weld metal and the occupancy of the cylindrical samples of casting metal mold of the proposed alloy and alloy prototype are shown in table 2.

Compared to the known alloy of the proposed alloy has the following advantages:

- the occupancy of small channels molds on average 2 times higher,

- flexibility higher on average in 2.5 �Aza;

- the work of destruction under impact bending (ATu) welds of the proposed alloy is 50% higher (ATu) well-known alloy.

Table 1
The chemical compositions of the present alloy and known alloy-prototype
AlloyAlCSiFeBO2VZrWC+O22(V+Fe+Si)/Al
13,00,020,120,020,0020,140,15--0,160,193
24,00,140,050,100,0030,050,10 -0,190,125
34,50,080,020,250,0050,100,02-0,18of 0.128
prototype5,00,180,200,35-0,20-0,800,200,38-

Table 2
The results of determination of plasticity, of fracture of the weld metal and the occupancy of the (proposed and known alloys)
Alloyδ, %ATuJ/m2St. seamThe occupancy rate
R�smery filled cylindrical samples (D×L, mm
2,5×2005,0×2007,5×20010×200
115,070,0200200200200
214,568,0200200200200
316,068,0200200200200
prototype6,040,075114162200

Foundry alloy based on titanium containing aluminum, carbon, oxygen, iron, silicon, characterized in that it further comprises vanadium and boron in the following ratio of components, wt.%:

aluminum3,0-4,5
carbon 0,02-0,14
oxygen0,05-0,14
iron0,02-0,25
silicon0,02-0,12
vanadium0,02-0,15
Borof 0.001-0.005
titanium and impuritiesthe rest,

when the following ratios:
(C+O2)≤0,20
2(V+Fe+Si)/Al≤0,20.



 

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Titanium material // 2544976

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy, namely to titanium materials with high strength and processibility. Titanium material contains iron 0.60 wt % or less and oxygen 0.15 wt % or less, titanium and inevitable impurities are the rest. Material has a non-recrystallised structure formed by processing accompanied by plastic deformation and a recrystallised structure formed by annealing after the above treatment; average size of recrystallised α-grains is 1 mcm or more and 5 mcm or less, and surface area of the non-recrystallised part in a cross section of titanium material is more than 0 to 30%.

EFFECT: material is characterised by high strength and processibility.

2 dwg, 2 tbl, 45 ex

FIELD: process engineering.

SUBSTANCE: invention relates to production of long articles from titanium or its alloy or blanks of such articles. Proposed method consists in preparation of titanium or titanium alloy mix (10), melting said mix by electric arc at scull melting (20), casting of one or several ingots, primarily cylindrical in shape, in diameter smaller than 300 mm from said fused mix (30). Then, said ingots are drawn at 800-1200°C at draw bench (40) for application in, for example, aircraft engineering.

EFFECT: higher quality, simplified production.

13 cl, 3 dwg

FIELD: metallurgy.

SUBSTANCE: alloy contains the following, wt %: titanium 46.3-48.8; aluminium 0.14-2.87, calcium 0.06-1.24; magnesium 0.08-1.61; and iron is the rest.

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1 tbl

FIELD: metallurgy.

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1 ex

FIELD: medicine.

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2 cl, 1 tbl

FIELD: metallurgy.

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2 dwg, 2 tbl, 2 ex

FIELD: metallurgy.

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2 cl, 2 dwg, 4 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: proposed alloy comprises the following elements, in wt %: carbon - 0.03-0.10; iron - 0.15-0.25; silicon - 0.05-0.12; nitrogen - 0.01-0.04; aluminium - 1.8-2.5; zirconium - 2.0-3.0; samarium - 0.5-5.0, titanium and impurities making the rest.

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3 tbl, 1 ex

FIELD: metallurgy.

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3 cl, 11 dwg, 1 ex

FIELD: metallurgy.

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1 tbl, 1 ex

FIELD: mechanical engineering; piston internal combustion engines.

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16 cl, 3 tbl, 1 ex, 15 dwg

FIELD: powder metallurgy, namely sintered titanium base alloys used as constructional materials.

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EFFECT: enhanced mechanical properties of alloy.

FIELD: metallurgy, namely processes for forging titanium alloys and blank of such alloy suitable for forging.

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8 cl, 5 tbl, 6 dwg, 4 ex

FIELD: metallurgy.

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EFFECT: improved properties and quality of alloy.

3 cl, 2 tbl, 3 ex

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SUBSTANCE: the invention is pertaining to the field of non-ferrous metallurgy, in particular, to the brick made out of α+β titanium alloy and to a method of its manufacture. The offered brick consists of the following components (in mass %): aluminum - 4-5, vanadium - 2.5-3.5, iron - 1.5-2.5, molybdenum - 1.5-2.5, titanium - the rest. At that the alloy out of which the brick is manufactured, contains - 10-90 volumetric % of the primary α-phase. The average grain size of the primary α-phase makes 10 microns or less in a cross-section plain parallel to the brick rolling direction. Elongation of grain of the primary α -phase is the four-fold or less. The offered method of manufacture of the given brick includes a stage of a hot rolling. At that before the stage of the hot rolling conduct a stage of the alloy heating at the surfaces temperature (Tβ-150)- Tβ°C. During realization of the stage of the hot rolling the surface temperature is kept within the range of (Tβ-300)-( Tβ -50)°C, and the final surface temperature, that is a surface temperature directly after the last rolling, makes (Tβ-300)-( Tβ-100)°C, where Tβ is a temperature of α/β-transition. The technical result of the invention is formation of a brick out of the high-strength titanium alloy having a super pliability, excellent fatigue characteristics and moldability.

EFFECT: the invention ensures production of a brick out of the high-strength titanium alloy having a super pliability, excellent fatigue characteristics and moldability.

7 cl, 7 dwg, 21 tbl, 2 ex

FIELD: nonferrous metallurgy; aircraft industry; mechanical engineering; development of alloys on the basis of titanium.

SUBSTANCE: the invention is pertaining to the field of nonferrous metallurgy, in particular, to development of alloys on the base of titanium, working at the heightened temperatures. It may be used in an aircraft industry for manufacture of components, for example, disks, vanes, rings, and also in mechanical engineering. The invention presents an alloy based on titanium and a hardware product produced out of it. The alloy contains aluminum, zirconium, stannum, niobium, a molybdenum, silicon, carbon and oxygen. At that it in addition contains tungsten and iron, at the following ratio of components (in mass %): aluminum 5.8 - 6.6, zirconium 2.0 - 4.0, stannum - 2.5 - 4.5, niobium - 0.8-2.5, molybdenum - 0.8- 1.5, silicon - 0.25-0.45, carbon - 0.05-0.1, oxygen -0.05-0.12, tungsten - 0.35-0.8, iron - 0.06-0.13, titanium - the rest. The technical result is a development of an alloy having the lower weight at the given short-time strength and a specific low-cycle fatigue, that increases an operational life and reliability of the components of the hot tract of aero-engines.

EFFECT: the invention ensures development of an alloy with the lower weight at the given short-time strength and a specific low-cycle fatigue with increased operational life and reliability.

2 cl, 2 tbl, 3 ex

FIELD: medicine; instrument-making industry; radio industry; production of materials with a memory effect of the form.

SUBSTANCE: the invention is pertaining to the materials with a memory effect of the form and with the modified surface, which may be used as implants in medicine and as the temperature sensors, thermo-sensitive and executive elements and designs in instrument-making industry, the radio industry. The offered material consists of a base made out of a titanium nickelide of the following composition (in at. %): titanium - 49-51, nickel - the rest, and the surface layer modified by alloying elements. The modified surface layer is formed by irradiation with a low-energy high-current electronic beam and has a depth of 1000-2500 nanometers and the dimensions of the crystal grains of no more than 30 nanometers. In the capacity of the alloying elements it contains oxygen and carbon at the following ratio of components (in at. %): oxygen - 10-20, carbon - 10-15, titanium - 40-50, nickel - the rest. The technical result of the invention is production of the materials with an effect of memory of the form and a high degree capability of the form restoration both at a low and high deforming loadings.

EFFECT: the invention ensures production of the materials with an effect of memory of the form and a high degree capability of the form restoration both at a low and high deforming loadings.

1 tbl, 1 ex

FIELD: metallurgy, in particular, titanium-based materials resistant to change of color.

SUBSTANCE: construction material of pure titanium contains, wt%: Fe 0.08 or less; Nb 0.02 or less; Co 0.02 or less, and is provided with surface oxide film having thickness of 170Å or less. Method involves producing material from pure titanium; etching and heating to temperature X( C) within the range of from 130 C to 280 C for time T (min) satisfying condition of T≥239408xX-2,3237.

EFFECT: increased resistance to change of color for prolonged time as compared to traditional materials.

3 cl, 2 dwg, 4 tbl, 3 ex

Titanium-base alloy // 2269584

FIELD: metallurgy.

SUBSTANCE: invention relates to titanium-base alloys used in making high-strength and high-efficient articles. Titanium-base alloy consists of aluminum, vanadium, molybdenum, iron and oxygen. Components of alloy are taken in the following ratio, wt.-%: aluminum, 3.5-4.4; vanadium, 2.0-4.0; molybdenum, 0.1-0.8; iron, max 0.4; oxygen, max 0.25, and titanium, the balance. Invention provides the development of universal alloy for large-sized forged pieces and stamps, thin-sheet roll and foil possessing the necessary strength and plastic indices and structure.

EFFECT: improved and valuable properties of alloy.

2 tbl

FIELD: metallurgy; high-strength alpha-beta alloys.

SUBSTANCE: Specification gives versions of titanium-based alpha-beta alloys. The proposed alloy contains the following components: aluminum, 4.5-5.5; vanadium, 3.0-5.0; molybdenum, 0.3-1.8; iron, 0.2-0.8; oxygen, 0.12-0.25; by-elements and admixtures, lesser than 0.1 each; total amount of by-elements and admixtures is lesser than 0.5; the remainder being titanium.

EFFECT: high strength of alloy, good workability and ballistic properties.

4 cl, 5 tbl, 3 ex

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