Method of manufacture of aluminium alloy highly resistant to damage
SUBSTANCE: said utility invention relates to the manufacture of products of a rolled aluminium alloy highly resistant to damage. The method involves casting an ingot with a chemical composition selected from the group consisting of AA2000, AA5000, AA6000, and AA7000 alloys, homogenisation and/or heating of the ingot after casting, hot rolling of the ingot into a hot-rolled product and, optionally, cold rolling of the hot-rolled product into a cold-rolled product. After the hot rolling, the hot-rolled product is cooled from the hot-rolling mill output temperature (Tout) to 150°C or lower, at a controlled cooling rate decreasing within the set range according to a continuous cooling curve determined using the following expression: T(t)=50-(50-Tout)eα-t, where T(t) is the cooling temperature (°C) as a function of the cooling time (hours), t is the cooling time (hours), and α is a parameter determining the cooling rate, within a range of -0.09±0.05 (hr-1).
EFFECT: enhanced impact strength; resistance to growth of fatigue cracks, and corrosion resistance without strength deterioration.
19 cl, 7 tbl, 1 dwg, 2 ex
The present invention relates to a method of manufacturing highly resistant to damage rolled aluminum alloy having good impact strength and improved resistance to the growth of fatigue cracks while maintaining good levels of strength, and to a sheet or plate product of aluminum alloy having a high impact strength and improved resistance to the growth of fatigue cracks. In addition, the invention relates to the use of products made of aluminum alloy obtained by the method according to the present invention.
In the art it is known the use of thermoablative aluminum alloys in many applications requiring relatively high strength, such as the aircraft fuselage of aircraft, parts of vehicles and other applications. Well-known thermoablative aluminum alloys are aluminum alloys AA2024, AA2324 and AA2524 that have useful strength and frictional properties in the States T3, kzt39 and T. Besides, it is well known thermoablative aluminum alloys are aluminum alloys AA and AA that have useful strength and frictional properties, and good resistance to the growth of fatigue cracks in both States T4 and T6.
It is known that the condition T4 alloy relative who are getting ready for the state after the heat treatment in the solid solution hardening, with the subsequent natural aging to essentially stable level properties, while the T6 condition refers to a state with higher strength obtained by artificial aging.
Some other alloys series AA and AA are usually unsuitable for constructing commercial (civil) air aircraft that requires different sets of properties for different types of constructions. Depending on the design criteria for a specific structural element of the aircraft, even a small improvement in toughness and resistance to crack growth, especially for high values ΔTo cause weight reduction, which translates into fuel savings throughout the life of your air aircraft and/or a greater level of security. Especially it is necessary to have properties such as good resistance to crack propagation either in the form of fracture toughness (crack resistance), or resistance to the growth of fatigue cracks, in the case of the fuselage skin and lower skin of the wing. Rolled products of aluminum alloy, used either in the form of a thin sheet or plate, with improved resistance to damage will increase passenger safety, reduce the mass air aircraft and bring the result to a greater range, lower costs and less frequent intervals between maintenance cycles.
In US-5213639 disclosed method of manufacturing aluminum alloy series AA alloys based on aluminum, which is rolled in a hot condition, heated and rolled again in a hot condition, thereby obtaining a good combination of strength together with high fracture toughness and a low rate of growth of fatigue cracks. Revealed that apply processing intermediate annealing after hot rolling the cast ingot to a temperature between 479 and 524°C and again hot rolling is subjected to intermediate annealing of the alloy. It is reported that this alloy has a 5%improvement, compared with the conventional alloys series A, in the longitudinal-transverse fracture toughness and improved resistance to the growth of fatigue cracks at certain levels ΔK.
It was reported that a known alloy AA is sensitive to intergranular corrosion in the T6 condition. In order to overcome this problem in US-5858134, proposes a method of production of rolled or forged product having a specified chemical composition, in accordance with which the product is brought to pereustroennogo condition requiring the manufacturer to be used in aerospace structural elements long paragraph is ocedur processing, consuming in the end, time and money. Here it is reported that to obtain improved resistance to intergranular corrosion essential in this method is that the ratio of Mg/Si in the alloy was less than 1.
In US-4589932 disclosed product of wrought aluminum alloy, for example, for the automotive and aerospace structures, which was subsequently registered under the trademark AA. Such aluminum alloy subjected to heat treatment in solid solution at a temperature in the range from 449 to 582°C, approaching the solidus temperature of the alloy.
In EP-A-1143027 disclosed method of manufacturing the Al-Mg-Si alloy series A having a specified chemical composition, and when this product is subjected to the procedure of artificial aging to improve the alloy and ensure compliance with the characteristics of high resistance to damage ("HDT"). high damage tolerance), similar to those characteristics of the alloys series AA, which, preferably, is used for aviation applications, but which are nesvarenie. The procedure of aging optimize using the appropriate function from structure.
In EP-1170394-A2 unfolded sheet product made of aluminum alloy with improved resistance to the growth of fatigue cracks with anisotropic microstructure characterized grains is with an average ratio of length to width is more than about 4. This alloy exhibits improved properties yield strength in compression, which achieved the relevant sheet items compared with the conventional rolled products of alloy AA. Resistance to the growth of fatigue cracks could be improved throughout vysokorentabelnoy granular structure.
In WO-97/22724 disclosed method and device for the production of rolled products made of aluminum alloy, in a typical case for use in vehicles with improved yield by continuous and rapid heating hot-rolled and cold-rolled thin sheet, which was subjected to heat treatment in solid solution and quenched to a temperature of pre-aging at the stage of continuous coagulation in a roll. After a quick heating of the sheet in the form of a roll is subjected to cooling in the environment, with rapid heating and cooling in the environment improve hardening response sheet of aluminum alloy on a hot drying paint coating (from the English. "paintbake response"). Revealed that is preferable to quickly heat rolled in the roll sheet to a temperature of from 65 to 121°C and select the cooling rate in the environment, which, preferably, should be between 1,1°C/h and 3.3°C/hour.
The present invention is, h is usually used to suggest a method of manufacturing aluminum alloy, having improved impact strength and improved resistance to the growth of fatigue cracks, thereby maintaining the levels of strength of conventional alloys series AA, AA, AA or AA. More specifically, the present invention is to provide an improved method for the production of highly resilient to damage (HDT) aluminum alloys with balanced properties in respect of resistance to the growth of fatigue cracks, toughness, corrosion resistance and durability. HDT properties, preferably, should be better than these same properties have usually produced alloys AA-T6, 6056-T6, and preferably better than the alloys AA-T3 or AA-T3.
More specifically, the total demand for rolled aluminium alloys series A, preferably in the range of aluminium alloys series AA and AA, when used for aerospace applications is the fact that the rate of growth of fatigue cracks ("FCGR"). fatigue crack growth rate should not be more than the specified maximum. FCGR that satisfies the requirements is highly resistant to damage to products made of aluminum alloy 2024 series, is, for example, FCGR below 0.001 mm/cycle at ΔK=20 MPa√m and 0.01 mm/cycle at ΔK=40 MPa√m
Another additional objective of the present invention is to offer rolled Adelie (product) of aluminum alloy for use in the aviation industry for the production of structural elements and parts, and also to offer cladding material air aircraft derived from this alloy, or offer the component of the vehicle.
The present invention solves one or more of the above objectives through the features of independent claims.
In one aspect of the present invention proposes a method of manufacturing highly resistant to damage aluminum alloy having high impact strength and improved resistance to the growth of fatigue cracks, which includes stages:
a) casting an ingot having a composition selected from the group consisting of alloys series AA, AA, AA and AA;
b) homogenizing and/or heating the ingot after casting;
c) hot rolling the ingot in a cold-rolled product and, optionally, additional cold rolling hot rolled products cold rolled products, characterized in that the hot-rolled product leaves the hot rolling mill at a temperature exiting the hot rolling mill (TOand cooling the hot rolled product from the above TOup to 150°C with adjustable cycle cooling with cooling rate, falling within the range specified by:
where T(t) represents the temperature (°C) as a function of time is (expressed in hours) t represents the time (expressed in hours) and α (expressed in hours-1is a parameter that determines the rate of cooling in the range -0,09±0,05 (h-1), and more preferably in the range -0,09±0,03 (h-1).
It was found that below a temperature of 150°C the cooling rate is not significant to achieve one or more of the benefits found in accordance with the present invention.
Although known from the prior art technology, trained specialists to cast ingot and subjected to the hot rolling to obtain a sheet or plate product, and this ingot optional heated or homogenized prior to hot rolling, the hot rolled product is quickly lost its increased temperature, resulting in deteriorated performance characteristics of this product. In accordance with the present invention it was found that by keeping hot rolled product at an elevated temperature for a specified time, exposing its regulated refrigeration cycle can be improved properties of resistance such rolled products to damage, such as impact strength and resistance to crack growth.
In the practical production on an industrial scale normal temperature is of exits the hot rolling mill are in the range from 350 to 500° C and depend on the alloy; for example, alloys series Aahhh outlet temperature will be in the upper part of this range from about 420 to 500°C, whereas alloys series Aahhh and Aahhh it will be in the lower part of this range of from about 350 to 425°C.
Additional cold rolling the cooled hot rolled products in the form of a roll is optional. Cold rolling may be direct or cross-rolling. Additional stages of intermediate annealing before, during or after cold rolling are also optional.
In addition, you can put hot rolled product clotting (winding) receipt roll form and, thus, to achieve a controlled rate of cooling up until the product has cooled to room temperature. Next, you can cut the roll into billets, which are then subjected to additional cold rolling. The material produced in this proposed invention technological route, showed a better balance of properties than the balance of the properties of hot rolled products, which were cut into the workpiece during or after hot rolling without collapsing into a roll (standard route plate (plate), or those products which have been folded into a roll after cold rolling (standard the route of thin sheet).
The second option of undergoing hot-rolled products regulated cooling cycle is phase continuous movement of the alloy through the furnace after hot rolling, and the furnace is regulated by the supply of heat and/or cold to the alloy during the passage to the location of its cold rolling or place collapse into a roll.
In an additional alternative embodiment, the rolled product is first subjected to hot rolling to the desired thickness, and then cooled to room temperature using conventional cooling. After that, the cooled hot rolled product is again heated to the temperature of the hot rolling mill, and then give him a chance to cool down to a temperature below 150°C, using an adjustable cooling cycle according to the invention, with subsequent additional processing.
Depending on, whether or not thin or thick sheets, hot rolled product or serves in the above-mentioned furnace after hot rolling or coiled after hot rolling, the additional processing performed on the rolls (route a thin sheet). If the product is cut into the plate during or after hot rolling, the additional processing performed on the thus obtained plates.
Furnace, preferably, is governed by the Oh to supply different amounts of heat near the site of hot rolling and other quantities of heat - at a greater distance from the place of the hot rolling, depending on the cooling rate, thickness, and other dimensions of hot-rolled products, leaving the place for hot rolling.
When the hot rolled product is subjected to controlled cooling cycle when you minimize into a roll, after hot rolling, the alloy can be rolled in an appropriate furnace, and in this case referred to the furnace, preferably, is also regulated by the supply of heat to regulate the cooling cycle.
In one embodiment, the hot-rolled product when exiting the hot rolling mill at a temperature exiting the hot rolling mill has a thickness in the range of up to 12 mm, preferably in the range from 1 to 10 mm, and most preferably in the range from 4 to 8 mm
In those cases, when the rolled product should be further subjected to a cold rolling operation, it is preferred that the total compression in the cold condition was in the range from 40 to 70% for further optimization of mechanical properties. The final thickness of the rolled products of aluminum alloy, preferably, is in the range from about 2 to 7 mm
The method in accordance with the present invention may optionally include one or more of the following stages:
(d) thermal treatment of solid is th solution of hot-rolled products after as it was subjected to a controlled cooling cycle, or cold-rolled product at a temperature and for a time sufficient to transfer in the solid solution of the soluble components in the alloy;
(e) quenching the heat-treated solid solution of the product from aluminum alloy by quenching under irrigation cooling or quenching by immersion in water or other quenching media;
(f) optional stretching or compression of the hardened products of aluminum alloy or cold deformation processing to relieve stress in a different manner, alignment sheet products;
(g) an optional aging tempered and optionally stretched or compressed products of aluminum alloy to achieve the desired state, which depends on the chemical composition of the alloy, but includes state T3, T351, T6, T4, T74, kzt76, T751, T7451, T7651, T77, T79.
In addition, it is possible to anneal and/or heating the hot-rolled ingot after the first operation of hot rolling, and then for cooling according to the invention again follows hot rolling products to final thickness after hot rolling. In addition, it is possible to carry out intermediate annealing of hot-rolled products before and/or during cold rolling. These technologies, which are known from the prior art, can be profitably used in which the procedure according to the present invention.
The average cooling rate when using a regulated cooling cycle according to the invention is in the range from 12 to 20°C/hour.
In one embodiment, the present invention is cast ingot for technological route opened here the method has the following composition (in wt.%): Si 0,6-1,3; Cu 0,04-1,1; Mn of 0.1-0.9; Mg 0,4-1,3; Fe 0.01 to 0.3; Zr<0,25; Cr<0,25; Zn<0,6; Ti<0,15; V<0,25; Hf<a 0.25, other elements, in particular impurities, less than 0.05 each and less than 0.20 in the amount, the rest is aluminum; and more preferably the alloys in the composition range AA or AA.
In another embodiment, the present invention uses the ingot with the following composition (in wt.%): Cu 3,8-5,2; Mg 0,2-1,6; Cr<0,25; Zr<0.25 and preferably 0.06 to -0,18; Mn≤0.50 Mn>0, and preferably>0,15; Fe≤0,15; Si≤0,15; and Mn-containing dispersoid; and incidental elements and impurities, less than 0.05 each and less than 0.15 in total, and the remainder essentially aluminum, and preferably one where the Mn-containing dispersoid at least partially replaced by Zr-containing dispersoids.
According to another variant implementation of the present invention in the method of the ingot with the following composition (in wt.%): Zn 5,0-9,5; Cu 1,0-3,0; Mg 1,0-3,0; Mn<0,35; Zr<0.25 and preferably 0,06-0,16; Cr<0,25; Fe<0,25; Si<0,25; Sc<0,35; Ti<0,10; Hf and/or V<0,25; other elements, usually impurities, less than 0.05 ka the Dogo and less than 0.15 in the amount the rest is aluminum. Typical examples are alloys within the range corresponding to AA, AA and AAG.
According to another aspect of the present invention proposed sheet or plate product made of aluminum alloy, which has high impact strength and improved resistance to the growth of fatigue cracks, and which is made of products of aluminum alloy produced according to the method, which was described above and which will be described in more detail below. More specifically, the present invention is most suitable for the production of sheet rolled products of aluminum alloy, which is a constructive element of air flying machine (airplane) or vehicle (car). Such rolled sheet product made of aluminum alloy can be used, for example, as the skin of the aircraft fuselage of an aircraft or a component part of the vehicle.
The above and other features and advantages of the method and products of aluminum alloys according to the present invention will become more apparent from the following detailed description of preferred embodiments and the drawing, which represents a typical cooling curve of aluminum alloy, cooled after the hot rolling using the method according to this invention.
In the first preferred embodiment of the present invention, two conventional alloy (AA6013 and AA6056) were cast and processed into sheet products. There were used two options for processing:
Route 1. Was used a standard process route for laboratory cast ingots with compositions of conventional alloys A and AA. Were cut out blocks of size 80×80×100 mm, homogenized, heated and subjected to hot rolling to a thin sheet of a thickness of 4.5 mm After hot rolling, hot-rolled products were as usual cooled to ambient temperature by using the fact that the thin sheet given the opportunity to cool in ambient air atmosphere to room temperature, brought to the place of cold rolling is subjected to cold rolling to a thickness of 2 mm and termoobrabotannyj for 20 min at 550°C, then hardened and aged to the T6 condition within 4 hours at 190°C.
Route 2. Ingots with the compositions of conventional alloys A and A laboratory were molded and cut to size 80×80×100 mm These blocks were homogenized, heated and subjected to hot rolling to a thickness of 4.5 mm Imitation collapse into a roll in a hot state in industrial scale was introduced by giving a hot rolled product the same terminology is eskay history, what would roll into a full-scale serial production. Other stages were observed the same as in Route 1. After cold-rolled cold-rolled product was termoobrabotannom at 550°C for 20 min, tempered and subsequently aged to the T6 condition at 190°C for 4 hours. The results are presented in Table 1.
|Overview of resistance (Rp, Rmwith the use of small European standard (small Euronorm), toughness specimen with notch (TS/RP), intergranular corrosion (IGP). "intergranular corrosion") depth and type of alloy compositions 6013 and 6056, processed in accordance with the above described Route 1 and Route 2 at two different predetermined values of the temperature of the hot rolling.|
|No.||Alloy||Route||The outlet temperature of hot rolling (°C)||Rp (MPa)||Rm (MPa)||TS/Rp-||Depth IGP (µm)||IGP|
From Table 1 we can see that rolled products showed better impact strength of the specimen with notch at higher outlet temperature of hot rolling while maintaining good levels of yield strength at elongation and ultimate tensile strength. In addition, there is improved intergranular corrosion, so that was about the Eden additional test in respect of resistance to the growth of fatigue cracks (table 2).
|Overview of resistance to the growth of fatigue cracks (FCGR) for sample No. 1, 2, 5, and 6 from Table 1 (higher outlet temperatures of hot rolling) at two different levels ΔK.|
|Alloy||Route||The outlet temperature of hot rolling (°C)||FCGR ΔK=30 MPa √m||FCGR ΔK=40 MPa √m|
Although resistance to the growth of fatigue cracks produced according to the invention of products, is almost identical to the resistance to the growth of fatigue cracks of the products produced in accordance with standard technological route, at lower values ΔK, the resistance to the growth of fatigue cracks is improved at higher values ΔK.
In accordance with another preferred embodiment of this izaberete the Oia was highly resistant to damage alloy with low copper content of the composition series AA in conditions of full-scale pilot production. The composition presented in Table 3.
|The composition is highly resistant to damage rolled products of alloy series AA wt.%, the rest is aluminum and inevitable impurities.|
The alloy was processed to a thin sheet product thickness after hot rolling 4.5 mm were Then applied the following three options for processing:
Route 1. Standard process route (After hot rolling no stage clotting in the roll).
Route 2. Proposed in the invention process route collapsing into a roll after hot rolling and hot and cold rolling in the same direction.
Route 3. Proposed invention technological route to collapse into a roll after hot rolling and hot and cold rolling in different directions (cross rolling).
All three of the above options treatments were applied to the next General technological route:
a. Direct casting of ingots of the alloy composition in accordance with the Table is her 3.
b. The homogenization of the cast ingots.
c. Heating homogenised ingot for 6 hours at 510°C and then hot rolling the heated ingots, lead to the fact that the outlet temperature is about 450°C at a thickness of 4.5 mm
d1. No clotting in the roll (=Route 1).
d2. Collapsing into a roll, cooling and cutting thick sheets (=line 2).
d3. Collapsing into a roll, cooling and cutting plate (=line 3).
e1. Cold rolling to a final thickness of 2 mm (Route 1).
e2. Cold rolling in the same direction as the hot rolling to a final thickness of 2 mm (line 2).
e3. Cold rolling in a direction different from hot rolling (cross rolling to a final thickness of 2 mm (line 3).
f. Heat treatment for 2 hours at 550°C.
g. Tensile cold-rolled products by 1.5-2.5%.
h. Aging to the state T6 at 190°C for 4 hours.
|Overview of resistance (Rp, Rmwith the use of small European standard, toughness specimen with notch (TS/RP), intergranular corrosion (IGC) of the finished products of aluminum alloy in accordance with Table 3, using three describe the data above technological routes 1, 2 and 3.|
|Route||Rp (MPa)||Rm (MPa)||Rp (MPa)||Rm (MPa)||TS/Rp -||The depth of the IGC (µm)|
|Longitudinal direction||Transverse direction||Cross-machine direction|
Along with the fact that the levels of strength could be saved, rolled products, which were produced in accordance with the technological routes 2 and 3 showed better impact strength of the specimen with notch and the best characteristics of intergranular corrosion. It was also measured the resistance of the growth of fatigue cracks and are presented in Tables 5 and 6.
|Resistance to the growth of fatigue cracks in mm/cycle for 5 different values Δfor products produced in accordance with the above t is geologicheskiy routes 1, 2 and 3.|
|Δ||Route 1||Route 2||Route 3|
|Values from Table 5 are relatively standard (Route 1).|
|Δ||Route 1||Route 2||Route 3|
The above examples show that the properties of mouth is echeveste to damage the sheet or plate products can be improved through the use proposed in the present invention method, and that resistance to the growth of fatigue cracks can be especially enhanced for higher values ΔK.
Figure 1 shows a typical curve of continuous cooling for aluminum alloy AA when cooled from the temperature of the hot rolling mill in the 440°C to a temperature below 150°C, while the metal sheet has a thickness of 4.5 mm and leaves the roll immediately upon exiting the hot rolling mill in accordance with one embodiment of the method according to this invention. Roll width was 1.4 meters. The temperature of the coil as a function of time are shown in Table 7 for the hot spot roll (located in the center and is indicated on figure 1 as "The hot spot" (hottest spot)and the coldest point (located on the edge of the roll and is listed as "the coldest place" (coldest spot) on Figure 1). Table 7 summarizes the temperature in the case of a roll with a width of 2.8 metres. In the case shown in Figure 1 cooling curve α approximately -0,084 h-1.
When a thin sheet with a thickness of from about 4.0 to 4.5 mm was allowed to cool from the temperature of the hot rolling mill to a temperature below 150°C, using the common practice of cooling, namely leaving the sheet to cool to normal still air after exiting the hot mill is Rocade without any folding operation in a roll or the like, α was usually in the range from-0.5 to -2 h-1, thus resulting in such a case, the sheet is cooled from the temperature of the hot rolling mill to a temperature of 150°C or less for a period of time less than 3 hours.
Adjustable cooling cycle follows the equation above and in the claims, and the average cooling rate from the 440°C to 150°C products in the rolled form is within the range from 12 to 20°C/hour.
|The temperature of the roll for products of alloy A with a thickness of 4.5 mm in the collapsed state as a function of time during cooling in accordance with the invention.|
|Time (hours)||Roll width of 1.4 meters||Roll width 2.8 m|
|The coldest point (°C)||The hot spot (°C)||The coldest point (°C)||The hot spot (°C)|
|10td align="center"> 187||199||204||222|
Having now a full description of the invention, the skilled in this technical field will be obvious that it can be made many changes and modifications without deviating from the scope or essence of the invention described here.
1. Method of manufacturing rolled products of alloy based on aluminum, includes stage
a) casting an ingot having a composition selected from the group consisting of alloys series AA, AA, AA and AA;
b) homogenizing and/or heating the ingot after casting;
c) hot rolling the ingot in the hot rolled product, and optionally cold rolling the hot-rolled products cold-rolled product, characterized in that after hot rolling the hot rolled product is cooled from the temperature of the hot rolling mill (Toup to 150°With or below the variable speed cooling, falling within a specified range according the curve continuous cooling, defined by the following expression:
where T(t) - cooling temperature (° (C) as a function of cooling time, h, t is the cooling time, h, α - the parameter that determines the rate of cooling and in the range of 0.09±0,05 h-1.
2. The method according to claim 1, characterized in that α is in the range of 0.09±0,03 h-1.
3. The method according to claim 1 or 2, characterized in that the adjustable speed cooling hot rolled products provide by maintaining the elevated temperature for a specified time.
4. The method according to claim 1, characterized in that the adjustable speed cooling hot rolled products provide folding of hot-rolled products in roll after hot rolling.
5. The method according to claim 1, characterized in that the adjustable speed cooling hot rolled products provide continuous moving after hot rolling through the furnace, which regulate the supply of heat to the product during its passage to the place of cold rolling or collapsing into a roll.
6. The method according to claim 1, characterized in that the adjustable speed cooling hot rolled products provide folding it into a roll after hot rolling in the furnace, which control the cooling rate of the product during the collapse.
7. The method according to claim 1, trichosis fact, that hot-rolled steel product has a thickness less than 12 mm at the exit of the hot rolling mill.
8. The method according to claim 7, characterized in that the hot-rolled product has a thickness in the range from 1 to 10 mm, and preferably in the range of from 4 to 8 mm
9. The method according to claim 1, characterized in that it further includes one or more of the following process steps:
(d) thermal treatment of solid solution of hot-rolled products after cooling or cold-rolled products;
(e) quenching the heat-treated solid solution of the product;
(f) optional stretching or compression of the tempered product;
(g) an optional aging tempered and optionally stretched or compressed products to achieve the desired state.
10. The method according to claim 9, characterized in that the average cooling rate of the hot rolled product is in the range from 12 to 20°S/h
11. The method according to claim 9, characterized in that the ingot has the following composition, wt.%:
Mn of 0.1-0.9
Fe 0.01 to 0.3
incidental elements and impurities of less than 0.05 each and less than 0.20 in the amount, the rest is aluminum.
12. The method according to claim 9, characterized in that the ingot cast within the range of the and of the composition of the alloy AA or AA.
13. The method according to claim 9, characterized in that the ingot has the following composition, wt.%:
Zr<0.25 and preferably 0,06-0,18
Mn≤0.50 Mn:>0, and preferably >0,15
incidental elements and impurities of less than 0.05 each and less than 0.15 in total, the rest is aluminum.
14. The method according to claim 9, characterized in that the ingot has the following composition, wt.%:
Zr<0.25 and preferably 0,06-0,16
Hf and/or V<0,25,
incidental elements and impurities of less than 0.05 each and less than 0.15 in total, the rest is aluminum.
15. The method according to claim 9, characterized in that the ingot cast within range of the alloy composition selected from the group AA, AA and AAG.
16. Sheet or plate rolled products of alloy based on aluminum, characterized in that it is obtained according to the method according to any one of claims 1 to 15.
17. The product according to item 16, characterized in that it is a constructive element of air aircraft or vehicle.
18. The product according to item 16 or 17, characterized in that it constitutes a wall of the aircraft fuselage of the aircraft or component is salvage tools.
19. The product of the alloy according to item 16 or 17, characterized in that it has a final thickness in the range from 2 to 7 mm
FIELD: non-ferrous metallurgy, in particular, manufacture of articles from industrial silumins.
SUBSTANCE: method involves providing hydrogen charging at temperature of 730-750 C during 0.5-1 hour; performing age treatment by heating to temperature of 200-300 C and holding within indicated temperature range; cooling in air. Method allows industrial silumins with reduced linear expansion coefficient to be produced within temperature range of from 200 C to 300 C.
EFFECT: increased efficiency in producing of silumins having low linear expansion coefficient.
1 dwg, 1 tbl, 1 ex
FIELD: process for plastic working of metals, may be used in aerospace industry, as well as in mechanical engineering and instrument building.
SUBSTANCE: method involves deforming blank by twisting which is performed within zone restricted by individual matrices by pulling blank via through openings provided in said matrices and having sections corresponding to shape of blank profile. Blank has section different from round section. Part of blank disposed between matrices is preliminarily twisted.
EFFECT: improved physico-mechanical properties of elongated articles, increased efficiency, and high metal utilization coefficient.
3 dwg, 2 ex
FIELD: foil or thin strips of refined aluminum with high purity degree used after treatment of surface by etching for making anodes of electrolytic capacitors, namely high - voltage capacitors.
SUBSTANCE: foil or thin-sheet strip of refined aluminum with purity degree more than 99.9% has surface zone with depth 10 nm containing 5 - 25 at.% of aluminum carbide. Foil or thin strip is produced by casting sheet of refined aluminum; homogenizing and hot rolling, cold rolling and subjecting it to final annealing. The last operation is realized in neutral atmosphere at adding gas containing carbon atoms for forming surface zone with depth 10 nm containing 5 - 25 at.% of aluminum carbide. Gas containing carbon atoms is selected from group including methane, propane, butane, iso-butane, ethylene, acetylene, propene, propyne and butadiene.
EFFECT: foil or strip having improved trend for etching and allowing enhance in addition working characteristics of electrolytic capacitors.
4 cl, 1 tbl, 1 ex
FIELD: plastic working of metals, possibly manufacture of blanks designed for producing hollow thin-wall articles such as aluminum tubes, bottles.
SUBSTANCE: method comprises steps of feeding initial predetermined-size material to pressing machine having working units. In said working units initial material is subjected to successive parametric pressing by transitions. Pressing is realized at speed directly proportional to specific pressure of pressing process according to relation: Vt = KPt where Vt -parametric pressing speed at time moment t; Pt - specific pressure of pressing process at time moment t; K = (Pend - Pst)tk - proportionality coefficient; Pend - specific pressure at pressing process termination; Pst - specific pressure at pressing process starting; tk - time period of pressing process.
EFFECT: improved quality of blanks, enhanced efficiency of production of ready articles.
2 cl, 1 dwg
FIELD: non-ferrous metallurgy, possibly working parts of Silumins.
SUBSTANCE: method comprises steps of performing cycle aging-quenching- aging. Soaking time period at temperature for heating at quenching and at aging is in range 15 - 30 min. Cycle quantity of heat treatment is one or more. Invention provides lowered linear expansion factors of Silumins in temperature range 150 - 300°C.
EFFECT: lowered linear expansion factor of Silumins.
1 tbl, 1 ex
FIELD: manufacture of hollow articles from aluminum alloys which are hardened by heat treatment.
SUBSTANCE: proposed method consists in manufacture of hollow semi-finished product which is subjected to pressure shaping at change of perimeter of cross section of freshly hardened hollow semi-finished product at permissible degree of deformation.
EFFECT: enhanced accuracy of articles at lesser roughness of surface.
FIELD: metallurgy; heat treatment of castings made from AK8M alloy.
SUBSTANCE: proposed method consists in annealing the castings made on base of AK8M aluminum and hardened by heat treatment. Castings are heated at temperature of 420-450C and are held at heat for two hours, after which they are cooled down in air.
EFFECT: enhanced ductility and reliability; improved quality of castings; possibility of dressing the castings without cracking.
FIELD: nonferrous metallurgy; methods of the thermal hardening of the aging aluminum alloys.
SUBSTANCE: the invention is pertaining to thermal treatment of the aging aluminum alloys suitable for hardening. The method includes three phases of the thermal treatment of such an aged alloy. At the first phase of the thermal treatment (a) they conduct the alloy curing at the heightened aging temperature, which facilitates the process of extraction of at least one dissolved element. The aging is conducted during the time span ensuring production of the non-aged alloy having no less than 40 % and no more than 85 % of the values of the maximal hardness and strength achieved at the complete treatment up to the state Т6. At the second phase conduct chilling of the non-aged alloy from the ageing temperature of the phase (a) to the much lower temperature from -10°С to 65°С. The chilling is conducted at the rather high speed with the purpose essentially to suspend primary extraction. At the third phase the cooled alloy is effected by the much lower ageing temperature, than the ageing temperature of the phase of (a) - for the further extraction of the dissolved element defined as «the secondary extraction». The technical result of the invention is the development of the method allowing to gain the improved combinations of mechanical properties.
EFFECT: the invention ensures development of the method allowing to gain the improved combinations of the aluminum alloy mechanical properties.
23 cl, 4 tbl, 15 dwg
FIELD: manufacture of clad sheets and belts of aluminum alloy by rolling.
SUBSTANCE: method comprises steps of cladding ingots of aluminum alloys with use of Silumin boards having anisotropy of their deformation properties similar to anisotropy of deformation properties of ingots. Then hot and cold multi-pass rolling process is realized. Cold rolling is terminated at temperature 165°C ± 5°C and then product is cooled in air. Silumin boards whose thickness consist 2 - 6% of pack thickness are used.
EFFECT: uniform cladding along length and width of coil, high quality of welding of cladding boards with ingot.
2 cl, 1 dwg, 2 tbl, 1 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, in particular, relates to aluminum-copper-magnesium system and provides alloy for manufacturing aerospace-destination welded articles capable of working under loadings not only at ambient temperatures but also at short and long-term elevated temperature action. Alloy has following chemical analysis, wt %: copper 4.5-7.0, magnesium 1.75-4.5, manganese 0.25-0.8, titanium 0.05-0.45, iron 0.05-0.45, silicon 0.02-0.2, beryllium 0.001-0.07, hydrogen 1.8·10-6-3.1·10-5, calcium 0.0001-0.08, cobalt 0.02-0.45; at least one of the following elements: nickel 0.001-0.05, chromium 0.001-0.05, or zinc 0.001-0.05; one of the following elements: zirconium 0.0555-0.45 or vanadium 0.055-0.45; and aluminum - the balance.
EFFECT: enabled preparation of deformable aluminum-based alloy and article therefrom showing good weldability, little hot brittleness, and high strength of welded joint at ambient and elevated temperatures.
4 cl, 2 tbl
FIELD: metallurgy, in particular aluminum-copper-magnesium alloys useful as structural materials in airspace technique.
SUBSTANCE: claimed alloy and article made of the same contain (mass %): copper 3.8-5.5; magnesium 0.3-1.6; manganese 0.2-0.8; titanium 0.5.10-6-0.07; tellurium 0.5.10-5-0.01, at least one element from group containing silver 0.2-1.0; nickel 0.5.10-6-0.05; zinc 0.5.10-6-0.1; zirconium 0.05-0.3; chromium 0.05-0.3; iron 0.5.10-6-0.15; silicium 0.5.10-6-0.1; hydrogen 0.1.10-5-2.7.10-5; and balance: aluminum.
EFFECT: alloy of high strength, crack resistance, durability and increased lightning resistance.
2 cl, 2 tbl, 1 ex
SUBSTANCE: invention relates to compositions of deformable aluminum-base alloys that can be used in automobile manufacture. Proposed alloy comprises the following components, wt.-%: zinc, 5.0-7.0; magnesium, 0.3-0.5; copper, 1.0-2.0; zirconium, 0.5-1.5; manganese, 0.3-0.5; titanium, 0.8-1.2; chrome, 0.15-0.25; silver, 0.5-1.5, and aluminum, the balance. Proposed and prepared alloy possesses the enhanced strength.
EFFECT: improved and valuable property of alloy.