Method of manufacture of products from pseudo-alloys molybden-copper
SUBSTANCE: method includes preparing the molybdenum charge, pressing the preform, sintering the preform to form a porous framework, contacting the side of the resulting preform with copper taken in excess, impregnating the preform with copper, and cooling it. The impregnated workpiece is cooled from the impregnation temperature to the crystallization temperature of copper. In the impregnated workpiece, a temperature gradient is created directed toward the area of the excess copper location from the opposite side of the workpiece, to allow the blank to cool from the side opposite to that region of excess copper.
EFFECT: increase in the relative density of products and the absence of anisotropy of physical properties.
FIELD: process engineering.
SUBSTANCE: invention relates to suture needles, particularly, to forming said needles from refractory alloys. Needle blank is made from doped alloy. Note here that said blank comprises refractory alloy. At least, part of said needle blank is heated to temperature exceeding that of transition from plastic to brittle state but lower than alloy recrystallisation temperature. Needle blank is formed mechanically to produce suture needle. Suture needle formed from refractory allows more than single shape recovery without fracture.
EFFECT: longer life, higher strength and hardness.
19 cl, 3 dwg, 2 ex
SUBSTANCE: invention relates to metallurgy of nonferrous metals, particularly, to production of foundry alloy for alloying refractory titanium-base alloys. Proposed composition contains the following substances, in wt %: tungsten 48.0-52.0, titanium 10.0-20.0, hafnium 0.08-0.1, aluminium making the rest. Charge is smelted in vacuum arc furnace with nonconsumable tungsten electrode. Note here that at first step, titanium placed on bottom of copper water-cooled casting mould and tungsten of higher density is placed there above. Titanium and tungsten are dissolved and melted in proportion corresponding to their content in foundry alloy to make integral ingot at arc current between charge and electrode of 750-1100 A and melting time of 3-10 min. To average ingot chemical composition, ingot is removed from casing mould to subject it to remelting at temperature higher than liquidus temperature of the alloy of titanium and tungsten. Then, required amount of aluminium and hafnium is added to remelted ingot to be placed under aforesaid ingot to proceed with melting at 1750-1900°C.
EFFECT: higher strength and heat resistance.
3 cl, 3 tbl
SUBSTANCE: manufacturing method of cast target for magnetron sputtering from molybdenum-based alloy and target obtained using the above method is proposed. Method involves obtaining of an ingot of alloy on the basis of molybdenum. First, high-purity polycrystalline molybdenum ingot is obtained by means of deep vacuum refining by electron-beam drip re-melting of a workpiece made from high-purity molybdenum; after that, arc vacuum remelting of high-purity polycrystalline molybdenum ingot is performed with strips from high-purity monocrystalline silicon; at that, the number of strips is chosen from the condition for obtaining polycrystalline alloy ingot with composition of molybdenum - 0.005-1.0 wt % of silicon, which is subject to machining.
EFFECT: improving the quality of semiconductor devices and integral circuits due to improvement of chemical resistance of films, as wells as stability of value of transient resistance of contacts at heat treatment.
2 cl, 2 tbl, 1 ex
SUBSTANCE: manufacturing method of composite target for obtaining films by magnetron sputtering and target obtained using the above method is proposed. Method involves manufacture of disc from polycrystalline titanium ingot obtained by multiple vacuum titanium re-melting, drilling of holes in staggered order in sputtered zone of titanium disc along two concentric circles and fixture of cylindrical inserts in them. Cylindrical inserts are made by cutting of ingots of monocrystalline tungsten and monocrystalline rhenium, which have been obtained by multiple vacuum remelting of tungsten and rhenium. Inserts attachment is performed by press fitting to drilled holes at the ratio of surface areas occupied with tungsten and rhenium inserts on surface of target in titanium disc providing the production of films consisting of the following, wt %: titanium 2.5-37.0, rhenium 0.04-9.78, and tungsten is the rest.
EFFECT: improving reliability and process barrier layers due to decreasing mechanical stresses and improving homogeneity of metal coating.
2 cl, 1 tbl, 1 ex
SUBSTANCE: manufacturing method of composite target for obtaining films by magnetron sputtering and target obtained using the above method is proposed. Method involves manufacture of disc from polycrystalline titanium ingot obtained by multiple vacuum titanium re-melting, drilling of holes in staggered order in sputtered zone of titanium disc along two concentric circles and fixture of cylindrical inserts in them. Cylindrical inserts are made by cutting of ingots of monocrystalline tungsten and monocrystalline silicon, which have been obtained by multiple vacuum remelting of tungsten and silicon. Inserts attachment is performed by press fitting to drilled holes at the ratio of surface areas occupied with tungsten and silicon inserts on surface of target in titanium disc providing the production of films consisting of the following, wt %: silicon 0.1-1.3, titanium 11-33, and tungsten is the rest.
EFFECT: increasing thermal stability of metal coating and reproducibility of its formation process.
2 cl, 1 tbl, 1 ex
SUBSTANCE: powders of tungsten and tantalum are mixed and rods are manufactured by hydrostatic extrusion of the mixture at a pressure of 140÷160 MPa for 3÷5 minutes. Then the rods are heat treated in vacuum with residual pressure of P≤8·10-3 Pa at a temperature of 800 °C. Then the rods are continued to be processed in a reducing atmosphere at a surplus pressure of at least 0.2 atm and a temperature of 800÷1000 °C for not less than two hours. Then the rods are heat treated in vacuum with residual pressure of P≤8·10-3 Pa at a temperature of T≥1500°C for not less than 2 hours followed by cooling. Heating and cooling under vacuum and the reducing atmosphere are carried out at a rate of 300÷400 °C/h. A mono-crystal bar is grown by crucibleless melting by means of cathode ray heating it is finished by even heat with seed melting to the end of the bar of odd heat.
EFFECT: production of mono-crystals of tungsten tantalum alloy with a high degree of uniformity of distribution of tantalum along the bar.
3 cl, 1 tbl
FIELD: process engineering.
SUBSTANCE: invention relates to powder metallurgy, particularly, to methods of producing porous articles from composite tungsten-based pseudoalloy. Proposed method may be used for making corrosion-proof materials that can efficiently dissipate mechanical power at dynamic loads and increase density on collision with obstacle. Pore-forming agent NaBr with particle fineness under 0.071 mm is added to charge containing 94-98 wt % of tungsten, nickel and iron making the rest in 7:3 ratio.Tungsten powder features Fischer mean particle size of 3.9 mcm. Aforesaid charge is compacted at not over 150 MPa and sintered at 1300-1320°C for 0.5-1.0 h in atmosphere of hydrogen.
EFFECT: porosity of 50-60%, high compression resistance, uniform fine structure.
SUBSTANCE: the invention relates to powder metallurgy, in particular, to heavy alloy powder products based on tungsten. The raw piece containing at least 95% of tungsten (rest - nickel and iron with the mass ratio equal to 7:3) is grinded to homogeneous powder mixture with particle size of about 100 nm by high-energy grinding with mechanical activation of the particles. The mass ratio of grinding pellets to raw powder mixture is 10:1. The rough powder pieces are formed by compression in hydrostat with pressure of about 50 MPa and subjected to electric pulse plasma sintering in the solid phase while heating in vacuum at the rate of 100-300°C/minute. The resulting product has the limit of macroelasticity of at least 2000 MPA, the limit of flowability of at least 2500MPA, at the density of ~18,0 g/cm3, and nanodispersed structure with particle size less than 500 nm. The concentration of tungsten atoms in the solid “nickel-iron” solution of γ-phase, based on nickel and doped by tungsten, is increased up to 20,4 %.
EFFECT: improved physical properties of the resulting product.
3 cl, 2 dwg.
SUBSTANCE: according to the first version there is used preliminary mixed charge containing components at following ratio, wt %: molybdenum concentrate 69, reducer 31. Thermal treatment is carried out in a graphite can at temperature of combustion 1400-1600°C during 10-15 min. According to the second version there is used preliminary mixed charge containing components at following ratio, wt %: molybdenite concentrate 53-55, reducer 15-17, iron containing compounds 25-27, slag forming components 3-5. Thermal treatment is performed in the graphite can at temperature of combustion 2000-2200°C during 30-40 min.
EFFECT: efficient and ecologically safe thermal process of production of molybdenum and its alloys.
6 cl, 1 tbl
FIELD: process engineering.
SUBSTANCE: invention relates to powder metallurgy. It may be used for producing materials that can efficiently dissipate mechanical power at dynamic loads. Tungsten powder with mean particle size to Fischer making 0.8-3.9 mcm is used to prepare charge composed of W 92.3-Ni 1.3-Cu 6.4 wt %. Sponging agent, ammonium bicarbonate with dispersity lower than 0.071mm, is added to charge for it to be compacted at 150 MPa, max. Then, sponging agent is removed and charge is sintered at 1080-1300°C for 1-2 hours.
EFFECT: produced material features porosity of 55-56%, high compression strength, no crak formation.
2 dwg, 1 ex
FIELD: process engineering.
SUBSTANCE: set of invention relates to production of articles from composites with carbide-metal matrix by vapour-fluid phase metalising. This process includes placing the porous blank and crucible with metal in closed retort and their heating to get metal vapours and to ensure metal mass transfer into blank material pores by metal vapour condensation, intermediate cooling, isothermal curing at maximum temperature of metalising and final cooling. Metalising is effected with the help of retort consisting of separated parts and by adjustment of permeability of butts between retort parts. Metal mass transfer into material pores is effected at decreased permeability of retort parts butt by their covering by fusible gate while final cooling is performed at higher permeability of retort parts butts by removal of overlapping butt of fusible gate. Invention covers the device for process implementation and process of permeability adjustment.
EFFECT: uniform metalising, reproducible results of metalising, longer life of retort.
3 cl, 6 dwg
SUBSTANCE: porous workpiece is submerged into molten matrix alloy, it is subject to vacuum degassing, heating and overpressure exploration due to thermal expansion of molten metal in tank enclosed volume. As molten matrix alloy molten lead is used, and during heating the workpiece is additionally treated, then cooled and crystallised. Used tank consists of two chambers: A chamber for treatment and a chamber for pressure generation. At that porous workpiece is submerged into molten aluminium matrix alloy in treatment chamber and is heated to 100°C above temperature of aluminium alloy liquidus simultaneously with molten lead in chamber for pressure generation.
EFFECT: composite material has high conductivity, antifriction properties and resistance to corrosive environment.
3 cl, 2 dwg, 1 tbl, 3 ex
SUBSTANCE: invention relates to making a grid for selective transmission of electromagnetic radiation, particularly X-ray radiation. The grid comprises a structural element having walls containing a plurality of particles which contain a first radiation-absorbing material. The particles are sintered together to form pores between adjacent particles. Said pores are at least partially filled with a second solid material which contains a radiation-absorbing material. The pores are filled by adding the second material in a liquid, preferably molten state.
EFFECT: improved mechanical stability of the grid and improved radiation absorption properties thereof.
10 cl, 5 dwg
FIELD: process engineering.
SUBSTANCE: invention relates to powder metallurgy, particularly, to production of drill bits by impregnation process. Solid element of the binder containing metal or metal alloy is placed to working mould. Matrix material powder layer is filled in the mould working cavity, material being based of transition metal carbide, or metal, or metal alloy containing carbide, and heated to allow transfer of fused binder from solid element for impregnation of said layer of matrix material powder. Said solid material can be placed in the channel communicated with moulding cavity in height hmv to feed fused binder from the channel at the level below 1/2hmv. This mould is heated to allow the passage for fused binder through the part of matrix material powder material for impregnation.
EFFECT: mean passage diameter is notably larger than mean intergranular pore of powder.
20 cl, 9 dwg, 1 tbl
SUBSTANCE: disposal graphite press mould is manufactured with through holes, which forms and sizes correspond to lower projection of bit matrix sectors section. During diamonds laying, loading, formation and matrix charge pressing, under graphite press mould placed is a base which upper surface reproduces profile of surface of matrix sectors lower part. At sintering in vacuum furnace the base is removed. Under each bit matrix sector placed are pellets of treated metal or alloy, so that treatment was performed from bottom to top.
EFFECT: providing self-adjusting and homogeneous dosing of treated metal or alloy in all the matrix sectors, matrix uniform density, improving yield ratio, excluding metal lapping on tool housing.
2 cl, 2 dwg
FIELD: process engineering.
SUBSTANCE: invention relates to powder metallurgy, particularly, to production of ball valve from titanium-carbide-based cermet. Ball valve cermet structure consists of alternating zones of continuous metal matrix and isolated uniformly distributed carbide grains and zones with continuous metal matrix and uniformly distributed carbide grains that make a continuous carcass. Content of metal matrix in cermet makes 25-70 vol. %. Ball valve made, mould with porous carbide semi after sintering is not withdrawn from the furnace, its temperature being maintained above liquidus temperature of impregnating metal. The latter is fused in crucible arranged in the same chamber, filled in the mould to contact with carbide semi and maintained for time interval required for complete infiltration of metal melt and directed crystallisation of metal in semi pores.
EFFECT: higher quality of ball valve made of cermet.
2 cl, 6 dwg, 4 ex
SUBSTANCE: fusible gate is formed between retort parts of siliconising plant at butts on the side of its outer surface. Said fusible gate is formed in end recess while fusible gate material is composed by Si3N4-Si or Ti3SiC5-Ti Si2-Si, or TiSi2-Si.Said materials are produced by impregnating them or Si3N4-or mix of TiC and Ti, or Ti-based porous blanks formed at circular recess bottom to overlap the butt with the melt of silicon melt or its alloys with Cu and Al.
EFFECT: higher degree and homogeneity of siliconising, longer life.
6 cl, 6 dwg
SUBSTANCE: composite material consists of coal-graphite frame saturated with matrix copper-based alloy containing the following components, wt %: phosphorus 4.0-8.0, zinc 0.5-12.5, iron 0.5-1.5, and copper is the rest.
EFFECT: improving the quality of composite material.
1 tbl, 5 ex
SUBSTANCE: invention refers to powder metallurgy, and namely to production of products from pseudoalloy materials such as tungsten-copper and molybdenum-copper. Workpieces are pressed from tungsten or molybdenum charge, sintered till tungsten or molybdenum frames are obtained, and sintered frames are saturated with copper. Prior to copper saturation of frames, their surface, except the sections through which copper saturation is performed, is coated at least with one layer of material resistant to saturation temperature and not wetted with molten copper.
EFFECT: producing the parts with density of up to 99,3-100% with absence of anisotropy of properties.
FIELD: process engineering.
SUBSTANCE: invention relates to powder metallurgy, particularly, to materials intended for production of polymer-metallic composite materials. It may be used for making magnetically soft materials for cores of inductors, stators and rotors of electric machines. Powder composition with lubing material is compacted to make billet to be heated to above lubing material evaporation temperature so that said material is, mainly, removed from compacted billet. Billet thus made is subjected to action of liquid polymer composite containing nano- and/or micro sized reinforcing structures and cured by drying and/or hardening. Produced composite part is formed by interpenetrating polymer networks between powder composition and polymer composite while reinforcing structures comprise one or several components selected from particles, plates, fibers, whiskers and tubes.
EFFECT: higher density and strength at higher temperatures, better machining properties.
25 cl, 5 tbl, 8 ex
SUBSTANCE: charge is prepared containing metal components of specified composition of the pseudoalloy by their mixing, the prepared charge is pressed. Billet is annealed in vacuum at pressure 1.33×10-2 Pa maximum, at temperature 300°C minimum and not exceeding melt temperature of low-melting component of the pseudoalloy for at least 1 h. Pseudoalloy billet is sintered in hydrogen atmosphere by two stages. At the first stage heating to temperature 800°C minimum is performed, at the second stage - to sintering temperature of specified charge with holding at these temperatures for at least 1 h, respectively. After sintering additionally axial pressing of the pseudoalloy billet is performed at pressure decreasing from 300 MPa to 80 MPa with rate 80 MPa/min max.
EFFECT: increased electrical conductivity and thermal conductivity of the composite material due to increasing of its homogeneity and reduction of temperature coefficient of linear expansion upon keeping high limit density.
2 cl, 1 tbl, 6 ex