Method of multipass cold rolling of thin bands from aluminium alloys
SUBSTANCE: in compliance with proposed method of rolling thin bands from aluminium Al-Mg or Al-Mg-Mn system alloys fully recrystallised hot-rolled band blank is subjected to rolling. Band blank features cubic texture and depth 9-10 times larger than band final depth. Rolling causes 45-47% reduction at every of two last passes at deformation rate of at least 10 m/s and band coiling temperature of 140-160°C, coil weight making at least 8 t.
EFFECT: higher metal ductility, decreased scatter of mechanical properties.
The invention relates to the processing of metals by pressure, for example, to the production of thin strips and foils of alloys of the system Al-Mg, Al-Mg-Mn and can be used, for example, in the metallurgical industry for the manufacture of thin films, for the production of packaging in the food industry.
There is a method of rolling systems Al-Mg containing cold rolling with intermediate recrystallization annealing, rolling before and after annealing lead with a total degree of deformation of 75-95%, the degree of deformation before annealing is 1-1 .25 from the degree of deformation after annealing (see A.S. 850235, WV 3/6, USSR, 1981).
The disadvantages of this method include:
1. The presence of intermediate annealing that when rolling on stage II does not provide the necessary strength characteristics.
2. The method does not provide high plasticity.
3. A large variability of mechanical properties.
4. Not provide the required level of festoons.
There is a method of rolled Al-Mg alloys containing cold rolling in several passes, in which the rolling carried out with the degree of deformation per pass 40-45%, while the aisles cooling the metal to 70-80°C (A.S. 878386, WV 3/0, USSR, 1981).
The disadvantages of this solution include:
1. Metal cooling between passes complicates the technological process and reduces p is poizvoditelnosti.
2. Implementation of rolling each pass with the degrees of deformation of 40-45% is possible on single-stand mill, but almost impossible to mnogoletija.
3. Does not allow for heavily cold-worked metal to receive the increased plasticity.
The closest technical solution of the present invention is a method for the production of foil by a method of multi-pass cold rolling thin strips of aluminum alloys, where each of the last two passages are rolling with the degree of compression for a given ratio between the tape options
where H is the initial thickness of the strip, h is the desired final thickness of the ribbon, K is a coefficient equal to 0,05-0,07 (see EN 2226437,7WV 3/00 from 10.04.2004), with a total degree of compression, amounting to at least 85%, with a minimum speed of 500 m/min and temperature at the end of the rolling, equal to 140-160°C when the mass of the roll 5 so
The disadvantages of this method include:
The degree of deformation calculated by this formula, is extremely small, which does not provide the necessary heating of the strip during cold rolling.
The task of the invention is to increase the plasticity and stanoevska treated metal and reduction of the scatter of mechanical properties.
The task in the present invention is achieved by way of a cold mnogo ohodnot rolling thin strips of aluminum alloys of the system Al-Mg or Al-Mg-Mn. While rolling is subjected to a fully recrystallized hot rolled billet tape having a cube texture and thickness, 9-10 times the final thickness of the ribbon, while the rolling is conducted with a degree of deformation of 45-57% in each of the last two passages and with the speed of deformation of at least 10 m/s in the last passage with maintenance of the temperature of 140-160°C in the coil by the winding of the tape into a roll weighing not less than 8 tons
When the degree of deformation <45% to be achieved in two passes required temperature at 140-160 degrees With the impossible. If the degree of deformation >57%, the temperature will be higher than necessary and the rolling process will become unstable. When the rolling speed <10 m/s fine stripe does not provide saving achieved the desired interval, when the winding into a roll. Without a fully recrystallized hot rolled billet is not guaranteed that the resource of plasticity required for high-speed rolling without destruction. In the absence of the cubic texture in hot-rolled workpiece has a strong fashionistas.the at an angle of 45° to the direction of rolling. The necessity of keeping the interval ratio of the thickness of, 9-10 times the final thickness of the ribbon, due to the fact that at <9 strength is not obtained, and at >10 occurs intense fracturing and buckling during rolling, and do not provide aceveda required fashionistas.the. For the mass of rolled billets <8 t the rate of natural cooling coil in the air does not provide the necessary residence time in the temperature range needed for the relaxation processes.
The proposed method of cold rolling for the above systems allows you to get a tape with high strength properties, plastic properties and stanoevska and reduce the spread of mechanical properties. For example, the ribbon alloy 3104 (system Al-Mg-Mn) thickness 0,265 mm, manufactured by the proposed method allows to obtain stable following mechanical properties (table 1):
|options||unit dimensions||treb. by M.S.||by th. method|
From the presented figures show that the parameter σinthe spread decreased by 4 times, and the parameter σ02- 8 times.
The goal of the invention is tested repeatedly, consistently provided results mentioned above.
The way multi-pass cold rolling thin strips of aluminum alloys of the system Al-Mg or Al-Mg-Mn, characterized in that the rolling is subjected to a fully recrystallized hot rolled billet tape having a cube texture and thickness, 9-10 times the final thickness of the ribbon, while the rolling is conducted with a degree of deformation of 45-57% in each of the last two passages and with the speed of deformation of at least 10 m/s in the last passage with maintenance of the temperature of 140-160°C in the coil by the winding of the tape into a roll weighing not less than 8 tons
SUBSTANCE: alloy contains, wt %: 3.5-4.5 zinc, 3.5-4.5 magnesium, 0.6-1.0 copper, 2.0-3.0 nickel, 0.25-0.3 zirconium, aluminium - balance, at the same time after strengthening thermal treatment the alloy has yield point of 570 MPa, strength limit of 600 MPa, hardness of 160 HY, and after deformation at 440-480°C with speed of 0.001-0.01 1/s the alloy has elongation of more than 500%.
EFFECT: production of alloy with equiaxial homogeneous fine-grain structure.
SUBSTANCE: aluminium-based alloy with lower density is designed for making deformed semi-finished products, including sheets used in aircraft building. The alloy contains the following components, wt %: magnesium 4.2-5.0; zinc 3,2-3.9; copper 0.4-1.0; scandium 0.17-0.30; zirconium 0.07-0.14; titanium 0.01-0.05; berillium 0.0001-0.005; hydrogen 0.05-0.35 cm3/100 g of metal; manganese < 0.25; chrome <0.10; iron <0.30; silicon <0.20; aluminium - balance, with the ratio of magnesium content and zinc content - 1.3. The method for processing of alloy includes homogenisation is carried out at 400-430°C for 6-15 hours, hot deformation - at temperature of 380-430°C, and cold deformation to the final size - at the total extent of hot and cold deformation of less than 80%.
EFFECT: alloy has higher strength in combination with lower density.
2 cl, 5 tbl
SUBSTANCE: method involves casting of an ingot and obtaining of workpiece from it using equal-channel annular pressing with back pressure. Reduction of duration of shape-generating operations performed in the mode of high-speed superplasticity, as well as reduction of the workpiece heating time is provided due to the fact that prior to the ingot casting, the molten metal is heated up to 760-800°C and exposed at that temperature during 0.5-1.0 h; ingot is cast by means of semi-continuous casting to sliding crystalliser; cast ingot is annealed at temperature of 360-380°C during 3-8 h; workpiece of rectangular section, which is square in plan view, is obtained from ingot with ratio of thickness to width of 0.17 to 0.33; deformation of workpiece obtained from the ingot by pressing is performed at crossing angle channels of 90° at temperature of 305-325°C with number of passes of 4 to 8, which corresponds to true deformation of ~4 to ~8, with back pressure value equal to 30-40% of the value of applied pressure, with rotation of workpiece after each pass through 90° relative to the axis perpendicular to large edge of workpiece and passing through the centre of workpiece; then, workpiece is subject to rolling at temperature of previous pressing with total swaging of 80-95% at temperature of working rolls of rolling mill, which is equal to rolling temperature.
EFFECT: optimisation of superplastic shaping process of products of irregular shape.
1 tbl, 1 ex
SUBSTANCE: plate of 10 mm thickness or larger from aluminium alloy features higher durability. Note here that said aluminium alloy has the following chemical composition with the following components, in wt %: Mg 4.0-6.0, Mn 0.2-1.4, Zn not over 0.9, Zr < 0.3, Cr < 0.3, Sc < 0.5, Ti < 0.3, Fe < 0.5, Si < 0.45, Ag < 0.4, Cu < 0.25, other elements and unavoidable impurities of each aforesaid element - <0.05, sum - <0.20, aluminium making the rest. Plate features elongation in L direction exceeding 10% and tensile strength making, t least, 330 MPa. Proposed plate is produced by casting, preheating and/or homogenising, hot rolling, first cold forming, annealing at less than 350°C, and second cold forming.
EFFECT: higher resistance to kinetic projectiles, better formability.
27 cl, 3 dwg, 2 tbl, 2 ex
SUBSTANCE: melt is overheated to a temperature of 760-800 °C with an exposure of 0.5-1.0 h, a billet is cast by continuous casting into the slide mould, the billet is annealed at a temperature of 360-380 °C for 3-8 h, production of a rectangular billet out of a square bar in the ratio of thickness to width ratio from 0.17 to 0.33. This is followed by deformation resulting from a bar of the billet using equal-channel angular pressing at an angle of channels intersection of 90 °C at a temperature of 305-325 °C with the number of passes of 8 to 10, which corresponds to a true deformation of 8 to 10, with back pressure equal to 40-50% of the applied pressure, and rotating the billet after each pass per 90 ° about the axis perpendicular to a bigger face of the billet, and passing through the centre of the billet. After the deformation of the billet using an equal channel angular pressing, cold rolling is carried out with a total compression of 75-80%, or cold rolling with a combined compression 80-95% followed by annealing at a temperature of 305-335 °C for 0.5-1.0 h with cooling to room temperature with a rate of 15-35 °C/h.
EFFECT: deformed billets with high mechanical strength while maintaining flexibility.
1 tbl, 1 ex
SUBSTANCE: there is received constructional material from alloy on the basis of aluminium, containing components at following ratios, wt %: magnesium 10.50-15.50, manganese 0.05-0.10, zirconium 0.01-0.15, titanium 0.09-0.15, silicon and iron not more than 0.08, aluminium is the rest. Crystallisation of melt is implemented in rotary crystalliser at gravitation coefficient, equal to 180-250, during time of melt existence, equal to 12-15 s/kg, and cooling rate not higher than 5°C/s. Ingot is thermal treated and rolled. At first it is heated during 2-4 hours at temperature 340-380°C, then at that temperature is implemented its hot rolling up to thickness 4-8 mm at a degree of deformation in each cycle up to 30% and final temperature of semi-finished rolled products in the range 310-330°C. Then it is implemented cold rolling of semi-finished rolled products at a degree of deformation in each cycle up to 50% with intermediate softening during 0.5-2.0 hours at tempearture 310-390°C up to required thickness 0.5-2.0 mm and it is implemented finish annealing of rolling during 5-40 minutes at temperature 400-450°C.
EFFECT: increased durability, plasticity and manufacturability of rolling.
2 dwg, 2 cl
FIELD: metallurgy industry.
SUBSTANCE: invention refers to metallurgy, and namely to methods of producing superductile plates from aluminium alloys of aluminium-magnesium-lithium system, and can be used for superductile moulding of complex-shaped parts, as well as structural material when producing extruded sections. From an ingot there made is a half-finished article in the form of a cylinder. Hardening is carried out at 460±10°C during 0.5 hour. After that the half-finished article is extruded in intersecting channels with diameter corresponding to diameter of half-finished article deformed with a shear at the temperature of 300-400°C with accumulated deformation degree e=10. Rolling is carried out at the temperature of 330-370°C.
EFFECT: producing plates with high homogeneity of mechanical properties and improved superductility indices at low temperatures and high metal flow rates.
1 tbl, 1 ex
SUBSTANCE: said utility invention relates to Al-Zn-Mg alloys, namely, to alloys for welded structures, such as structures used in marine construction, during manufacture of car and industrial vehicle bodies, and stationary or movable tanks. The method involves manufacture of a plate using semi-continuous casting. The plate is made of an alloy containing, % weight: Mg 0.5-2.0, Mn < 1.0, Zn 3.0-9.0, Si < 0.50, Fe < 0.50, Cu < 0.50, Ti < 0.15, Zr < 0.20, Cr < 0.50, aluminium with its inevitable impurities being the remaining, Zn/Mg > 1.7. After that, the plate is subjected to homogenisation and/or reheating at a temperature T1 selected so that 500°C ≤T1≤(Ts-20°C) where Ts is the alloy burning temperature. The first hot rolling stage includes one or several rolling passes on a hot-rolling mill, the input temperature T2 is selected so that (T1-60°C)≤T2≤ (T1-5°C), and the rolling process is performed in such a way that the output final temperature T3 would be so that (T1-150°C)≤T3≤(T1-30°C) and T3 < T2. The strip produced at the said first hot rolling stage is rapidly cooled to the temperature T4. The second stage of hot rolling of the said strip is performed at the input temperature T5 selected so that T5≤T4 and 200°C≤T5≤300°C. The rolling process is performed in such a way that the coiling temperature T6 would be so that (T5-150°C)≤T6≤(T5-20°C).
EFFECT: enhancement of balance between mechanical properties and corrosion resistance of base metal and welded joint using simplest and most reliable method.
34 cl, 8 dwg, 20 tbl, 10 ex
FIELD: foundry and rolling processes.
SUBSTANCE: structural material contains following components, wt %: magnesium 9.0-11.0, zirconium 0.15-0.2, cobalt 0.01-0.001, beryllium 0.001-0.02, boron 0.005-0.007, aluminum - the balance. Crystallization of melt is carried out in rotary crystallizer at gravitation coefficient 220-250 and melt lifetime 12-15 sec/kg. Ingot is first heated for 2-4 h at 340-380° C and then subjected to hot rolling at that temperature until thickness 4-8 mm is attained at deformation rate up to 30% in each cycle and final rolling temperature 310-330° C. Thereafter, cold rolling is effected with deformation rate up to 50% in each cycle and intermediate annealings for 0.5-2.0 h at 310-390° C until required thickness 0.5-2.0 mm is attained followed by final annealing of rolled metal for 5-40 min at 400-450° C.
EFFECT: increased strength, plasticity, and processability of aluminum-based alloy with 9-11% magnesium.
2 cl, 2 dwg, 1 tbl
FIELD: nonferrous metallurgy.
SUBSTANCE: invention is intended for use in metallurgy, mechanical engineering, and aircraft industry, in particular for manufacturing honeycomb structures. Alloy is composed of, wt %: magnesium 8-10, manganese 0.1-0.15, zirconium 0.15-0.2, cobalt 0.05-0.2, boron 0.005-0.007, beryllium 0.001-0.02, iron 0.15-0.2, silicon 0.15-0.2, titanium 0.1-0.2, aluminum - the balance. Ingot for manufacturing structural foil is obtained by semicontinuous casting in rotary crystallizer at volumetric cooling 4-20°C/sec. Structural foil manufacturing process comprises homogenization, hot rolling, annealing, cold rolling followed by annealing in air atmosphere, second cold rolling followed by annealing, and final cold rolling.
EFFECT: increased strength of alloy at ambient and elevated temperatures and improved processability un rolling stage.
3 cl, 3 tbl
SUBSTANCE: proposed method comprises hot forming of slab, hot rolling and teat treatment of plate, whereat hot forming if carried out in one step. Immediately after reaching required thickness in slab forming it is quickly cooled to the depth of 20-30 mm at the rate of at least 50°C/min. Subsequent hot lengthwise rolling at performed at first step in α+β-area by partial reduction with deformation degree εi varying from 3% to 5% to total deformation ε=25…30% with breaks between passes of 8 to 12 s. At second step, it is performed in β-area from heating temperature determined by definite formula. At the next step rolling is performed in α+β-are with breaks and heating in lengthwise or transverse directions with total degree of deformation e after every break to 60%.
EFFECT: homogeneous fine-grain microstructure, high and stable mechanical properties, high precision, no surface defects.
SUBSTANCE: invention relates to production of thin sheets from ingot of pseudo-alpha titanium alloy. Proposed method comprises forming ingot of alloy Ti-6.5Al-2.5Sn-4Zr-1Nb-0.7Mo-0.15Si into slab and machining of the latter. Then, said slab is heated to temperature exceeding that of polymorphic transition, deformation and multistep rolling to semi-finished rolled stock with regulated total degree of deformation and degree of deformation in a pass. Sheets are stacked, stacks are rolled to finished size and subjected to multipass rolling with regulated total deformation, sheets are extracted from the stack and subjected to finishing.
EFFECT: high and uniform strength and plastic properties.
1 dwg, 2 tbl
SUBSTANCE: proposed method comprises smelting of alloy, making slab, machining its surface, hot, warm, and cold rolling, sintering and ageing. Smelted is pseudo-beta-titanium alloy with aluminium content not higher than 5.0 wt % and molybdenum equivalent No eq. ≥ 12 wt %, calculated by the following formula: Mo eq. wt % = %Mo + %Ta/4 + %Nb/3.3 + %W/2 + %V/1.4 + %Cr/0.6 + +%Fe/0.5 + %Ni/0.8 + %Mn/0.6 + %Co/0.9. Semi-finished 8-2 mm-thick rolled stock produced in hot and cold rolling is subjected, prior to cold rolling, to quenching at Tpt+(20-50°C) for 0.1-0.5 h with cooling. Cold rolling is performed to sheet thickness of 6-1 mm in signal-phase beta-state in two and more steps in several passes with 1-6%-reduction in one pass and total reduction at every step of 30-50%. Note here that intermediate quenching is carried out between said steps in conditions identical to quenching of semi-finished rolled stock before cold rolling.
EFFECT: high-quality rolled thin sheets.
5 dwg, 2 tbl
FIELD: process engineering.
SUBSTANCE: invention is intended for increasing quality of sheets and ruling out pollution originating in forming special magnesium alloys doped with high-toxicity light-volatile elements that form, in heating and forming, harmful oxides, and may be used in production of sheets for anodes of electrochemical current sources. Proposed method comprises placing round ingot in tubular shell, hearing the workpiece and its hot and warm rolling to requited sheet thickness.
EFFECT: higher quality of sheets and process efficiency.
FIELD: process engineering.
SUBSTANCE: invention relates to metallurgy, particularly, to forming semis from titanium alloy BT6 and may be used in machine building, aircraft engineering and medicine. Proposed method comprises annealing at 850°C with holding for an hour in furnace to create globular (α+β)-structure and multipass rolling combined with affecting semis to pulsed electric current with density of 50-200 A/mm2, frequency of 830-1000 Hz, pulse duration of 100-120 ms to ensure total true strain degree of e>1 and to form nanocrystalline structure in semi. Note that, after every pass, semi is water cooled. Higher forming capacity of alloy is provided for.
EFFECT: higher strength at optimum ductility.
5 cl, 1 dwg, 1 tbl, 1 ex
FIELD: process engineering.
SUBSTANCE: proposed method comprises making ingots or powder billets. The latter are subjected to hot thermo mechanical machining, including sandwich rolling and finish cold rolling. Foil material mechanical properties are stabilised and material structure is blended in sandwich rolling at semi-finished rolled stock thickness of 2-4 mm with premade fine structure wherein grain width does not exceed 10 mcm while its length makes 40 mcm. Sandwich is composed of a set of semi-finished rolled billet and two steel covering plates. Note here that top covering plate thickness is 1.4-1.8 times larger than that of bottom plate. Hot rolling of sandwich is started from 950±50°C in several passes with total deformation of 70-90%. After annealing at 920±70°C and sandwich disassembly, cold rolling of every billet is performed at total deformation of 40-70% with intermediate vacuum annealing at 920±70°C.
EFFECT: higher foil quality made from titanium aluminide-based alloys based on Ti2AlNb orthorhombic phase.
2 cl, 4 dwg, 2 tbl
FIELD: process engineering.
SUBSTANCE: proposed method comprises stage-by-stage grinding of titanium billet grains by abc-forming and multi-pass rolling in grooved rolls with stepwise reduction in groove section at fixed temperature of billet heating for rolling. Increased mechanical properties are ensured by stepwise grain grinding at stepwise temperature reduction in the range of 750-500°C. In abc-forming, titanium billets made be subjected to recrystallisation annealing at 680-700°C for 1 h. Rolling in grooved rolls is performed at reducing billet temperature by 40-60°C at every pass to groove smaller section from 500°C to 300°C whereat rod final round cross-section is formed. The number of groove cross-sections id selected to provided for reduction not exceeding 40% in transition from one groove to another. Rolling is performed in several passes on turning the billet through 90 degrees about lengthwise axis. 4-8 mm-dia round titanium billets are produced to meet high purity standards.
EFFECT: higher metal yield.
6 cl, 2 tbl, 3 ex
SUBSTANCE: method to manufacture cold-deformed pipes from double-phase alloys based on titanium includes ingot smelting, ingot forging in a β-area or β- and α+β-area with forging completion in the α+β-area into an intermediate blank with the specified forging reduction. The intermediate blank is produced with forging reduction of at least 1.35, a block is made from the intermediate blank, which is pressed into a billet and thermally treated at the temperature that is by 30°-40°C below the temperature of Tint, and them the billet is rolled with intermediate surface treatment, etching and thermal treatment. Drawing in process of rolling is defined using the following formula.
EFFECT: produced pipes are characterised by high physical-mechanical properties due to exclusion of formation of grain-to-grain microcracks.
4 tbl, 1 ex
FIELD: process engineering.
SUBSTANCE: invention is intended for making high-strength rolled sheet from aluminium alloys. Proposed method comprises making flat billet and lengthwise cold rolling to target thickness. Note here that cold rolling is performed at -80 to -196°C with total reduction of 35-99%. After rolling to thickness exceeding target thickness by 2.8-9.5 times, billet is turned through 90 degrees in rolling plane.
EFFECT: higher strength and toughness.
2 cl, 1 tbl
SUBSTANCE: method for obtaining high-strength wire from (α+β)-titanium-based martensite alloy involves obtaining of ingot, its hot deformation so that workpiece for drawing is obtained; drawing at room temperature till final size is obtained, and final heat treatment. After heat treatment is completed, the obtained workpieces are annealed in the air and machined; drawing is performed for many times with intermediate annealings in the air environment; at that, the machining is performed after the first drawing pass, and final heat treatment is performed in the air environment during 60-180 minutes at temperature of (0.5÷0.7)TSL °C with further cooling to room temperature.
EFFECT: increasing ultimate tensile strength at maintaining the high level of relative elongation due to uniformity of the structure throughout the length and section of wire.
1 tbl, 2 ex
FIELD: plastic working of metals, possibly manufacture of thin high-strength foil of titanium.
SUBSTANCE: method comprises steps of multi-pass reversing cold rolling and vacuum annealing; repeating cycle; using as initial blank titanium blank with ultra-fine grain structure provided due to intensified plastic deformation by equal-duct angular pressing process; rolling at pitch 15 - 8% for achieving total deformation 70 - 86 % per one cycle; setting number N of cycles necessary for making foil with thickness h according to mathematical expression; realizing vacuum annealing, preferably at temperature 350 -360 C for 0.5 - 1 h. Invention provides possibilities for making titanium foil with thickness up to 10 micrometers.
EFFECT: enhanced strength characteristics of titanium foil of lowered thickness with the same technological platicity7777.
2 cl, 2 tbl