CN112935187A - Thick and large aluminum alloy frame body casting and casting method thereof - Google Patents
Thick and large aluminum alloy frame body casting and casting method thereof Download PDFInfo
- Publication number
- CN112935187A CN112935187A CN202110121376.8A CN202110121376A CN112935187A CN 112935187 A CN112935187 A CN 112935187A CN 202110121376 A CN202110121376 A CN 202110121376A CN 112935187 A CN112935187 A CN 112935187A
- Authority
- CN
- China
- Prior art keywords
- casting
- thick
- aluminum alloy
- sand mold
- alloy frame
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000005266 casting Methods 0.000 title claims abstract description 86
- 238000000034 method Methods 0.000 title claims abstract description 43
- 229910000838 Al alloy Inorganic materials 0.000 title claims abstract description 31
- 239000004576 sand Substances 0.000 claims abstract description 51
- 230000008569 process Effects 0.000 claims abstract description 18
- 238000001035 drying Methods 0.000 claims abstract description 10
- 238000001816 cooling Methods 0.000 claims abstract description 9
- 238000005422 blasting Methods 0.000 claims abstract description 7
- 238000004140 cleaning Methods 0.000 claims abstract description 7
- 238000004519 manufacturing process Methods 0.000 claims abstract description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 7
- 230000000171 quenching effect Effects 0.000 claims abstract description 4
- 230000002431 foraging effect Effects 0.000 claims abstract description 3
- 238000010791 quenching Methods 0.000 claims abstract description 3
- 229910045601 alloy Inorganic materials 0.000 claims description 16
- 239000000956 alloy Substances 0.000 claims description 16
- 239000007788 liquid Substances 0.000 claims description 14
- 244000035744 Hura crepitans Species 0.000 claims description 6
- 229910001018 Cast iron Inorganic materials 0.000 claims description 4
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 4
- 229910052782 aluminium Inorganic materials 0.000 claims description 4
- 238000007599 discharging Methods 0.000 claims description 4
- 238000010438 heat treatment Methods 0.000 abstract description 10
- 238000000465 moulding Methods 0.000 abstract description 9
- 239000000047 product Substances 0.000 abstract description 6
- 239000012043 crude product Substances 0.000 abstract description 2
- 238000012797 qualification Methods 0.000 abstract 1
- 230000000052 comparative effect Effects 0.000 description 10
- 238000010586 diagram Methods 0.000 description 10
- 230000032683 aging Effects 0.000 description 9
- 239000006104 solid solution Substances 0.000 description 8
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 7
- 230000009286 beneficial effect Effects 0.000 description 7
- 230000005496 eutectics Effects 0.000 description 5
- 239000013078 crystal Substances 0.000 description 4
- 230000007547 defect Effects 0.000 description 4
- 239000011856 silicon-based particle Substances 0.000 description 4
- 238000007711 solidification Methods 0.000 description 4
- 230000008023 solidification Effects 0.000 description 4
- 238000013461 design Methods 0.000 description 3
- 229910052742 iron Inorganic materials 0.000 description 3
- 239000003973 paint Substances 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- 238000005728 strengthening Methods 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- 238000004220 aggregation Methods 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 238000007528 sand casting Methods 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/02—Sand moulds or like moulds for shaped castings
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/08—Features with respect to supply of molten metal, e.g. ingates, circular gates, skim gates
- B22C9/082—Sprues, pouring cups
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/22—Moulds for peculiarly-shaped castings
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D15/00—Casting using a mould or core of which a part significant to the process is of high thermal conductivity, e.g. chill casting; Moulds or accessories specially adapted therefor
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/18—Hardening; Quenching with or without subsequent tempering
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/002—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working by rapid cooling or quenching; cooling agents used therefor
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/04—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon
Abstract
The invention relates to the technical field of aluminum alloy casting, in particular to a thick and large aluminum alloy frame body casting and a casting method thereof. The method comprises the following steps: s1, manufacturing a casting sand mold, and performing shot blasting cleaning and drying on the chilling block; wherein, both sides of the sand mould are provided with gates; s2, placing the dried chilling block into a sand mold to obtain a sand mold, and stripping the mold after the sand mold is dried and hardened; the thickness of the lower molding surface of the chilling block is larger than that of the upper molding surface of the chilling block; s3, performing mould assembling and pouring on the sand mould to obtain a casting crude product; s4, preserving the temperature of the crude casting at 543 +/-2 ℃ for 14h, and quenching with room temperature water; then preserving heat for 5.5h at the temperature of 155 +/-2 ℃ for aging treatment; and then cooling to room temperature in the air to obtain the product. According to the casting method, the die of the thick and large part is reformed, and the optimized heat treatment process is combined, so that the elongation of the part can be greatly improved, the overall performance of the casting method completely meets the aviation industry standard, and the qualification rate of products is greatly improved.
Description
Technical Field
The invention relates to the technical field of aluminum alloy casting, in particular to a thick and large aluminum alloy frame body casting and a casting method thereof.
Background
The cast aluminum alloy has the advantages of high strength, low density, low hot cracking tendency, good weldability, corrosion resistance, low production cost and the like, so that the cast aluminum alloy becomes an irreplaceable important material in the industrial fields of aviation, aerospace, navigation, automobiles and the like. The rack casting made of ZL114A alloy is an important part for aerospace, but the mechanical property of some parts is low due to the complex structure and uneven wall thickness of the casting. The part connected with other workpieces is in a plate shape with the thickness of about 51mm, and the part is thicker than the grain structure of other parts, so that the mechanical property is low, particularly the elongation is extremely low, the navigation mark requirement is difficult to meet, and the application of the navigation mark is limited.
The main method for producing the castings at present is sand mold low-pressure antigravity casting molding and then T6 heat treatment. The existing casting method has the following problems:
1) the cooling speed of the whole thick part is insufficient, so that the crystal grains are thick, and the mechanical property is difficult to meet the navigation mark requirement.
2) The alloy liquid is finally solidified at the hanging ring positioned at the water inlet, so that a thermal node exists, the mechanical property is worst, and potential safety hazards exist.
3) The quality of the casting is unstable, the ultrasonic flaw detection is unqualified, and the air hole defect is always existed at the upper bottom surface.
Disclosure of Invention
In order to solve the problems, the invention aims to provide a casting method of a thick and large aluminum alloy frame body type casting, which can effectively improve the mechanical property of a part where the casting is connected with other workpieces, reduce the defect of air holes and improve the yield.
In order to achieve the above object, the technical solution of the present invention is as follows.
The invention provides a casting method of a thick and large aluminum alloy frame body casting, which comprises the following steps:
s1, manufacturing a casting sand mold, and performing shot blasting cleaning and drying on the chilling block;
the lower profile of the sand mold is provided with a hanging ring, and two sides of the sand mold are provided with pouring gates;
s2, placing the dried chilling block into a sand mold to obtain a sand mold, and stripping the mold after the sand mold is dried and hardened;
the thickness of the chilling block close to the lower molded surface of the sand mold is larger than that of the chilling block close to the upper molded surface of the sand mold;
s3, placing the sand mold in a sand box for mould assembling and pouring, and after pouring is finished, discharging sand and cleaning to obtain a crude casting product;
s4, preserving the temperature of the crude casting at 543 +/-2 ℃ for 14h, and quenching with room temperature water; then preserving heat for 5.5h at the temperature of 155 +/-2 ℃ for aging treatment; and then cooling to room temperature in the air to obtain the thick and large aluminum alloy frame body casting.
Further, in S1, the chiller is a trapezoidal cast iron chiller.
Further, in S1, a sidewall of the chilling block is engraved with a plurality of exhaust grooves staggered with each other.
Further, in S2, the thickness of the chill near the upper mold surface of the sand mold is greater than or equal to the thickness of the casting.
Further, in S1, the drying process of the chilling block is drying at 250 ℃ for 2 h.
Furthermore, in S2, chills are placed on one side of each sand mold close to the corresponding gate.
Further, in S1, the quantity of rings is 2, and the chilling block has been placed between 2 rings.
Further, in S3, the mold assembling and pouring process includes: the pouring system is positioned at the bottom of the sand box, the pouring temperature is set to be 670-675 ℃, and the alloy liquid is fed from the corresponding pouring gate to the bottom upThen, carrying out boosting treatment; the boosting process comprises the following steps: first, the pressure is raised to 5400X 10 within 20-27 s-5Maintaining the pressure for 6s under MPa to crust the aluminum liquid; then boosting the pressure to 6400X 10-5And (5) MPa, and keeping the pressure for 10 minutes.
The invention also provides a thick and large aluminum alloy frame body casting cast by the method, and the casting has good elongation rate while keeping certain compressive strength.
A thick large aluminum alloy frame body type casting, comprising:
one end of the frame body is provided with a thick and big part;
2 gate parts arranged at two sides of the thick part;
the boss is arranged on the upper side of the thick and large part;
2 hanging rings which are arranged on one end of the boss in parallel;
a first placing area is arranged on one side, away from the lifting rings, of the boss, second placing areas are arranged on two sides of the boss, a third placing area is arranged on one side, close to one of the gate positions, of the thick part, a fourth placing area is arranged among the 2 lifting rings, and a fifth placing area is arranged on one side, close to the third placing area, of the thick part; the first placing area, the second placing area, the third placing area, the fourth placing area and the fifth placing area are respectively used for placing corresponding chills.
The invention has the beneficial effects that:
1. the method of the invention is beneficial to fully drying the moisture on the surface and inside of the chilling block by performing shot blasting treatment and drying on the chilling block, and prevents air holes from being formed in the casting molding process. In addition, the design of the exhaust grooves on the surface of the chilling block can effectively reduce the generation of air hole defects in the casting process, and is beneficial to improving the quality and the yield of castings.
2. The material, shape and thickness of the chilling block capable of effectively improving the mechanical properties of the thick part are obtained through repeated experiments. The design that the bottom surface of the chilling block is thick and the upper surface of the chilling block is relatively thin is beneficial to sequential solidification of alloy liquid from bottom to top, meanwhile, the chilling block with proper thickness is placed near 2 gates, the problems that crystal particles are thick and the mechanical property is low due to thermal junctions at the gate parts are effectively solved, and meanwhile, the mold filling and solidification of the alloy liquid are not influenced.
3. The invention improves the position and the number of the pouring gates, effectively solves the potential safety hazard caused by lower performance of the flying ring part, and the design of the double pouring gates improves the mold filling speed and the mold filling stability of the alloy liquid in the pouring process, reduces the generation of defects and improves the quality and the yield of castings.
4. The invention improves the mould structure of the lifting ring, cuts a whole thick and large semi-cylinder into two parts from the middle, removes partial machining allowance, and adds the chill between the two lifting rings, thereby improving the solidification speed of the alloy liquid at the position, leading the grain size to be more compact, and further improving the mechanical property of the lifting ring.
5. The method reasonably optimizes the heat treatment process, and can further improve the mechanical property of the alloy through solid solution strengthening and precipitation strengthening. The solid solution temperature is properly increased, the spheroidization of eutectic silicon particles can be promoted by selecting proper solid solution time, the aggregation and growth of the eutectic silicon particles are avoided, and the tensile strength and the elongation rate can be improved to a certain extent at the same time. The variety and the quantity distribution of precipitated phases can be regulated and controlled by adjusting the aging process to obtain a microstructure which is beneficial to improving the plasticity of the alloy, and the elongation of the alloy is effectively improved on the basis of ensuring certain strength.
Drawings
Fig. 1 is a schematic structural view of a casting according to example 1 of the present invention.
Fig. 2 is a schematic structural view of a chiller in embodiment 1 of the present invention. Wherein, fig. 2a is a schematic structural diagram of a chiller I; FIG. 2b is a schematic structural diagram of chiller II; FIG. 2c is a schematic structural diagram of chiller III; FIG. 2d is a schematic structural diagram of a chiller IV; fig. 2e is a schematic structural diagram of the chiller V.
Fig. 3 is a schematic structural view of a casting of comparative example 1.
Fig. 4 is a metallographic structure diagram of a thick and large part of a frame body in example 1 of the present invention.
FIG. 5 is a fracture morphology diagram of the thick part of the scaffold body in example 1 of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
Referring to fig. 1, a schematic structural diagram of a thick and large aluminum alloy frame casting according to an embodiment of the present invention is shown, where the casting includes: the structure comprises a frame body 10, 2 gate parts 12, a boss 13 and 2 lifting rings 14.
One end of the frame body 10 is provided with a thick part 11; 2 gate parts 12 are respectively arranged at two sides of the thick and big part 11; the boss 13 is arranged on the upper side of the thick large part 11; 2 rings 14 are arranged in parallel on one end of the boss 13.
A first placing area 101 is arranged on one side, away from the hanging rings 14, of the boss 13, second placing areas 102 are arranged on two sides of the boss 13, a third placing area 103 is arranged on one side, close to one of the gate positions 12, of the thick and large part 12, a fourth placing area 104 is arranged among the 2 hanging rings 14, and a fifth placing area 105 is arranged on one side, close to the third placing area 103, of the thick and large part 11; the first placing area 101, the second placing area 102, the third placing area 103, the fourth placing area 104 and the fifth placing area 105 are respectively used for placing corresponding chills 15. Of course, there are 5 chills, i.e., chiller I, chiller II, chiller III, chiller IV, and chiller V, as shown in a-e of fig. 2. The chiller I is placed in the first placing area 101; the chiller II is placed in the second placing area 102; the cold iron III is placed in the third placing area 103; the chiller IV is placed in the fourth placing area 104; the chiller V is placed in the fifth placing area 105.
Specifically, the cold iron I and the cold iron II attached to the surface of the frame body are designed on the boss and on two sides of the boss, the surface of the boss is covered, and the thickness of the boss is about 70-90 mm, as shown in fig. 2a and 2 b. Meanwhile, a chiller IV and a chiller V with proper thicknesses are also added between the two lifting rings and on the left side surface of the thick and large part, as shown in fig. 2d and 2 e. And the chiller III is a trapezoidal cast iron chiller, the thickness of the thickest part in the middle is increased to 65mm, and the thickness of the thinnest part at the two ends is about 45mm, so that a temperature gradient can be formed more favorably to accelerate the cooling speed, as shown in fig. 2 c.
In order to exhaust air better and reduce the formation of air holes, a plurality of mutually staggered exhaust grooves are carved on one side wall of the main chilling block, and each exhaust groove is in an equilateral triangle shape with the side length of 3 mm.
Specifically, the gate size of the gate portion is reduced to about 45 × 65mm to reduce the thermal budget.
The casting method of the thick and large aluminum alloy frame body casting provided by the embodiment of the invention comprises the following steps:
s1, performing shot blasting treatment on the chills I-V before molding, and cleaning sand inclusion in the exhaust grooves of the chills; fully drying the water on the surface and inside of the chilling block after the shot blasting is finished, and keeping the temperature at about 250 ℃ for 2 hours to prevent air holes from being formed in the casting molding process;
s2, manufacturing a casting sand mold;
the lower profile of the sand mould is provided with a hanging ring, and two sides of the sand mould are provided with pouring gates;
and manufacturing a sand mold according to the structural shape of the thick and large aluminum alloy frame body type casting, and adopting resin sand molding, wherein the upper mold is a plane with a large thickness part, the lower mold is a plane with a hanging ring at the large thickness part, the pouring gate is positioned at two side surfaces of the large thickness part, and horizontal pouring is carried out from the two side surfaces. The whole thick part is made of a wood mould with a corresponding shape.
S3, placing the dried chills I-V on corresponding positions in a sand mold respectively to obtain a sand mold die;
wherein, the thickness of the chilling block close to the lower molded surface of the sand mold is larger than that of the chilling block close to the upper molded surface of the sand mold; the thickness of the chill close to the upper molding surface of the sand mold is larger than or equal to the thickness of the casting.
After the molding is finished, drawing the mold after the sand mold is fully dried and hardened;
and (3) quickly and uniformly coating the surface of the inner cavity of the sand mold with alcohol paint, and then quickly igniting after the alcohol paint is coated. Wherein, the cold iron part is not coated with paint, but is baked again by a blast lamp before the box is closed to ensure that the moisture is completely dried.
S4, fully inspecting the sand mold, and placing the sand mold into a sand box to close the box and prepare for pouring;
the pouring temperature is 670-675 ℃, the pouring system is positioned at the lower half part of the sand box, the alloy liquid enters from the bottom to the top from the pouring gates at the two sides, and the pressure is increased to 5400 multiplied by 10 at a constant speed in the pressure increasing process-5Under the MPa, the boosting time is about 20-27 s, and the pressure is maintained for 6s to crust the aluminum liquid; then continuously raising the pressure to 6400 multiplied by 10 at a constant speed-5And (5) maintaining the pressure at MPa for about 10 minutes.
S5, after pouring is completed, sand is discharged and cleaned, and a casting crude product is obtained;
the sand discharging and cleaning process mainly comprises the steps of shot blasting and sand removing, cutting and pouring systems, and polishing the surface of the casting until no sand holes, slag holes, burrs and the like exist.
S6, heat treatment, wherein the heat treatment process comprises the following steps: the crude casting is firstly kept warm for 14h at the temperature of 543 +/-2 ℃ and quenched with room temperature water; and then carrying out aging treatment immediately. The aging treatment process comprises the following steps: keeping the temperature at 155 +/-2 ℃ for 5.5 h; and then discharging the cast product from the furnace, and cooling the cast product to room temperature in the air to obtain the thick and large aluminum alloy frame body casting.
Comparative example 1
Please refer to fig. 3, which is a schematic structural diagram of a conventional thick and large aluminum alloy frame casting. The casting includes: a frame 20, 1 gate location 22, a boss 23, and 1 lift ring 24.
One end of the frame body 20 is provided with a thick part 21; the thick portion 21 has a boss 23, one end of the boss 23 has a cylindrical hanging ring 24, and the upper side of the hanging ring 24 has a gate portion 22.
The existing chilling block is a straight aluminum alloy chilling block with the thickness of 30mm, and is added at one end of a thick part without a hanging ring. The cooling speed of the whole thick part is insufficient, so that the crystal grains are thick, and the mechanical property is difficult to meet the navigation mark requirement.
The prior casting method of the thick and large aluminum alloy frame body casting is basically the same as the method of the embodiment 1, and the difference is that,
s2, a pouring gate is arranged on the lower profile of the sand mold and is positioned at the position of the hanging ring; the mechanical property of the part is reduced, and potential safety hazards exist. And the alloy liquid is finally solidified at the hanging ring positioned at the water inlet, so that a thermal node exists, the mechanical property is worst, and potential safety hazards exist.
S6, carrying out heat treatment, wherein the solid solution temperature in the heat treatment process is 538 (+/-2); the aging process is 160 (+/-2) DEG C.times.6 h ℃.
As can be seen by comparing the embodiment 1 with the comparative example 1, in the comparative example 1, the mechanical property of the part is reduced due to the fact that the opening is positioned at the position of the hanging ring, and potential safety hazards exist. Example 1 the original gate was removed and two gates were added on both sides. The total number of gates is changed from 1 to 2, and the gate size is reduced to about 45 × 65mm to reduce thermal budget.
The hanging ring at the thick and large part of the frame body in the comparative example 1 is an integral cylindrical hanging ring, which is not beneficial to cooling aluminum liquid, influences the tissue density and reduces the mechanical property. Example 1 the flying ring was cut off from the middle into two pieces to reduce the processing margin.
In sand casting, in order to improve the mechanical property of a certain part of a casting, a chilling block is usually placed at a required position, the solidification speed of alloy liquid is increased through the quenching effect of the chilling block, and the grain size of the alloy is refined. The chiller of comparative example 1 is a straight square 30mm thick aluminum alloy chiller added to the end of the thick part without a hanging ring. Example 1 the end chill was changed to a trapezoidal cast iron chill, the thickness of the thickest part in the middle increased to 65mm, and the thinnest part at both ends about 45mm, which would be more conducive to forming a temperature gradient and increasing the cooling rate, as shown in fig. 2c for chill III. In addition, in the embodiment 1, the surface of the hanging ring is covered by the chiller attached to the surface of the frame body, and the thickness of the chiller is about 70-90 mm, as shown in the chills I and II in the figures 2a and 2 b. Meanwhile, chills with proper thickness are also added between the two lifting rings and on the left side surface of the thick part, as shown by chills IV and V in figures 2d and 2 e. In order to better exhaust and reduce the formation of air holes, an equilateral triangle exhaust groove with the side length of 3mm is carved on one surface of the main chilling block.
The embodiment 1 optimizes the heat treatment process, firstly, the solid solution temperature is increased from 538 (+ -2) DEG C to 543 (+ -2) DEG C, the solid solution time is 14h, the morphology of eutectic silicon can be further improved through more sufficient solid solution treatment, the solid solution strengthening effect is enhanced, and the comprehensive performance of the alloy is improved; and secondly, reducing the aging temperature and shortening the aging time by a proper amount, wherein the aging process is changed from the original 160 (+ -2) DEG C6 h DEG C to 155 (+ -2) DEG C5.5 h. Therefore, the number of fine dispersed GP (I) areas and beta 'phases can be effectively increased, and the generation of disc-shaped beta' phases which are not beneficial to elongation is reduced, thereby realizing the purpose of further improving the elongation on the basis of ensuring certain strength.
It is noted that excessive raising of the solution temperature and time easily causes overburning or causes further aggregation and growth of eutectic silicon particles, resulting in a decrease in mechanical properties. Meanwhile, excessive reduction of the aging temperature and the aging time easily causes lower hardness and substandard strength. A large number of experiments prove that the process is the optimal heat treatment process suitable for the rack castings.
The mechanical properties of the casting obtained in example 1 were compared with those of the casting obtained in comparative example 1, and the results are shown in table 1.
Table 1 comparison of mechanical properties of thick and large portions of castings of example 1 and comparative example 1
| Number of castings | Average tensile strength | Average elongation | |
| Comparative example 1 | 5 are provided with | 286MPa | 0.96％ |
| Example 1 | 5 are provided with | 319.4MPa | 7.9％ |
The results in table 1 show that the average tensile strength of the thick and large part of the frame prepared in example 1 is 319.4Mpa, and the average elongation after fracture is 7.9%, which is greatly improved compared with the process of comparative example 1 and is obviously higher than 300Mpa and 4% of the standard requirements of the aviation industry.
FIG. 4 is a metallographic structure diagram of a thick and large portion of a frame prepared in example 1.
As can be seen from fig. 4, the crystal grain size of the thick and large part of the frame body obtained in example 1 is greatly refined, and meanwhile, eutectic silicon particles are generally distributed in a fine spherical shape, so that the mechanical property of the casting is greatly improved.
FIG. 5 is a fracture morphology of the thick portion of the scaffold prepared in example 1.
As can be seen from FIG. 5, the fracture at the thick part of the frame body presents a large number of dimples, which are obvious plastic fracture characteristics. Therefore, the frame body casting process in the embodiment 1 is simple and easy to implement, reasonable and effective in transformation of a die with a large part and low in cost, and can greatly improve the elongation of the part by combining the optimized heat treatment process, so that the overall performance of the part completely meets the aviation industry standard, and the product yield is greatly improved.
The present invention is not limited to the above preferred embodiments, and any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (9)
1. The casting method of the thick and large aluminum alloy frame body casting is characterized by comprising the following steps of:
s1, manufacturing a casting sand mold, and performing shot blasting cleaning and drying on the chilling block;
the lower profile of the sand mold is provided with a hanging ring, and two sides of the sand mold are provided with pouring gates;
s2, placing the dried chilling block into a sand mold to obtain a sand mold, and stripping the mold after the sand mold is dried and hardened;
the thickness of the chilling block close to the lower molded surface of the sand mold is larger than that of the chilling block close to the upper molded surface of the sand mold;
s3, placing the sand mold in a sand box for mould assembling and pouring, and after pouring is finished, discharging sand and cleaning to obtain a crude casting product;
s4, preserving the temperature of the crude casting at 543 +/-2 ℃ for 14h, and quenching with room temperature water; then preserving heat for 5.5h at the temperature of 155 +/-2 ℃ for aging treatment; and then cooling to room temperature in the air to obtain the thick and large aluminum alloy frame body casting.
2. A casting method of a thick and large aluminum alloy frame body casting according to claim 1, wherein in S1, the chiller is a trapezoidal cast iron chiller.
3. A casting method of a thick and large aluminum alloy frame-like casting according to claim 1 or 2, wherein in S1, a plurality of exhaust grooves are engraved on one side wall of the chill, wherein the exhaust grooves are staggered with each other.
4. A method for casting a thick large aluminum alloy frame-like casting according to claim 1, wherein in S2, the thickness of said chiller near the upper surface of said sand mold is greater than or equal to the thickness of the casting.
5. A casting method of a thick and large aluminum alloy frame body casting according to claim 1, wherein in S1, the drying process of the chilling block is drying at 250 ℃ for 2 h.
6. A casting method of a thick and large aluminum alloy frame body casting according to claim 1, wherein in S2, chills are placed on one side of each sand mold close to the corresponding sprue.
7. The casting method of a thick and large aluminum alloy frame casting according to claim 1, wherein in S1, the number of the hanging rings is 2, and chills are placed between 2 hanging rings.
8. The casting method of a thick and large aluminum alloy frame casting according to claim 1, wherein in S3, the mould assembling and pouring process comprises the following steps: the pouring system is positioned at the bottom of the sand box, the pouring temperature is set to be 670-675 ℃, alloy liquid enters from the corresponding pouring gate from bottom to top, and then pressure boosting treatment is carried out; the boosting process comprises the following steps: first, the pressure is raised to 5400X 10 within 20-27 s- 5Maintaining the pressure for 6s under MPa to crust the aluminum liquid; then boosting the pressure to 6400X 10-5And (5) MPa, and keeping the pressure for 10 minutes.
9. A thick large aluminum alloy frame-like casting cast by the method of claim 1, comprising:
one end of the frame body is provided with a thick and big part;
2 gate parts arranged at two sides of the thick part;
the boss is arranged on the upper side of the thick and large part;
2 hanging rings which are arranged on one end of the boss in parallel;
a first placing area is arranged on one side, away from the lifting rings, of the boss, second placing areas are arranged on two sides of the boss, a third placing area is arranged on one side, close to one of the gate positions, of the thick part, a fourth placing area is arranged among the 2 lifting rings, and a fifth placing area is arranged on one side, close to the third placing area, of the thick part; the first placing area, the second placing area, the third placing area, the fourth placing area and the fifth placing area are respectively used for placing corresponding chills.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110121376.8A CN112935187B (en) | 2021-01-28 | 2021-01-28 | Thick and large aluminum alloy frame body casting and casting method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110121376.8A CN112935187B (en) | 2021-01-28 | 2021-01-28 | Thick and large aluminum alloy frame body casting and casting method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112935187A true CN112935187A (en) | 2021-06-11 |
| CN112935187B CN112935187B (en) | 2022-08-02 |
Family
ID=76238989
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110121376.8A Expired - Fee Related CN112935187B (en) | 2021-01-28 | 2021-01-28 | Thick and large aluminum alloy frame body casting and casting method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112935187B (en) |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008142764A (en) * | 2006-12-13 | 2008-06-26 | Nissan Motor Co Ltd | Casting/molding method for cast/molded article having cylindrical part, and casting/molding device therefor |
| CN101876042A (en) * | 2010-06-23 | 2010-11-03 | 贵州安吉航空精密铸造有限责任公司 | Heat treatment method for improving intensity of ZL114A aluminium alloy castings |
| JP2012121040A (en) * | 2010-12-07 | 2012-06-28 | Mitsubishi Heavy Ind Ltd | Method for manufacturing casting mold |
| US20130160961A1 (en) * | 2011-12-21 | 2013-06-27 | Bedloe Industries Llc | Subsurface chills to improve railcar knuckle formation |
| CN106825407A (en) * | 2016-12-22 | 2017-06-13 | 常州中车汽车零部件有限公司 | A kind of sand mold manufactures component and casting method |
| CN107695306A (en) * | 2017-11-08 | 2018-02-16 | 山东美陵化工设备股份有限公司 | Wheel hub template and wheel hub casting technique |
| CN109175236A (en) * | 2018-09-13 | 2019-01-11 | 湖北三江航天红阳机电有限公司 | The tapered whole shell section casting and molding method of large thin-wall aluminum alloy round |
| CN109396378A (en) * | 2018-11-17 | 2019-03-01 | 共享装备股份有限公司 | The method for arranging of chill |
| CN110014123A (en) * | 2019-04-19 | 2019-07-16 | 山东国创风能装备有限公司 | Hundred tonnes of spentnuclear fuels store and transport the moulding process and iron sand group co-casting of integrated canister |
| CN111673072A (en) * | 2020-06-22 | 2020-09-18 | 北京航空航天大学 | Wheel forming device and method based on center pressurization of multiple lift pipes |
| CN111804888A (en) * | 2020-08-20 | 2020-10-23 | 北京航空航天大学 | Wheel antigravity casting equipment with crucible heat preservation stove |
-
2021
- 2021-01-28 CN CN202110121376.8A patent/CN112935187B/en not_active Expired - Fee Related
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008142764A (en) * | 2006-12-13 | 2008-06-26 | Nissan Motor Co Ltd | Casting/molding method for cast/molded article having cylindrical part, and casting/molding device therefor |
| CN101876042A (en) * | 2010-06-23 | 2010-11-03 | 贵州安吉航空精密铸造有限责任公司 | Heat treatment method for improving intensity of ZL114A aluminium alloy castings |
| JP2012121040A (en) * | 2010-12-07 | 2012-06-28 | Mitsubishi Heavy Ind Ltd | Method for manufacturing casting mold |
| US20130160961A1 (en) * | 2011-12-21 | 2013-06-27 | Bedloe Industries Llc | Subsurface chills to improve railcar knuckle formation |
| CN106825407A (en) * | 2016-12-22 | 2017-06-13 | 常州中车汽车零部件有限公司 | A kind of sand mold manufactures component and casting method |
| CN107695306A (en) * | 2017-11-08 | 2018-02-16 | 山东美陵化工设备股份有限公司 | Wheel hub template and wheel hub casting technique |
| CN109175236A (en) * | 2018-09-13 | 2019-01-11 | 湖北三江航天红阳机电有限公司 | The tapered whole shell section casting and molding method of large thin-wall aluminum alloy round |
| CN109396378A (en) * | 2018-11-17 | 2019-03-01 | 共享装备股份有限公司 | The method for arranging of chill |
| CN110014123A (en) * | 2019-04-19 | 2019-07-16 | 山东国创风能装备有限公司 | Hundred tonnes of spentnuclear fuels store and transport the moulding process and iron sand group co-casting of integrated canister |
| CN111673072A (en) * | 2020-06-22 | 2020-09-18 | 北京航空航天大学 | Wheel forming device and method based on center pressurization of multiple lift pipes |
| CN111804888A (en) * | 2020-08-20 | 2020-10-23 | 北京航空航天大学 | Wheel antigravity casting equipment with crucible heat preservation stove |
Non-Patent Citations (2)
| Title |
|---|
| 付明: "Q1―202盘铣刀架体铸造工艺", 《金属加工(热加工)》 * |
| 鲍壮等: "冷连轧机架铸造工艺及组织性能浅析", 《热加工工艺》 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112935187B (en) | 2022-08-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101530892B (en) | Investment casting thin-walled part casting method | |
| CN100519797C (en) | Al-Mg alloy sheet with excellent formability at high temperatures and high speeds and method of production of same | |
| CN110468361B (en) | Preparation method of deformed high-temperature alloy fine-grain bar | |
| CN111676404B (en) | Improved die casting forming method | |
| CN1253269C (en) | Casting extruding compound shaping method of magnesium alloy automobile hub | |
| JP2011115812A (en) | Method for producing light alloy vehicle wheel | |
| CN105689611B (en) | A kind of single head hub splines processing technology | |
| CN112872261A (en) | Forging method of titanium alloy flange plate forge piece | |
| CN112935187B (en) | Thick and large aluminum alloy frame body casting and casting method thereof | |
| CN109332631B (en) | Low-temperature die-casting process for communication box body | |
| TW200427850A (en) | Aluminium alloy exhibiting high mechanical strength and low quench sensitivity | |
| CN111360199A (en) | Alloy composition of alloy casting side guide plate | |
| CN101758181A (en) | Novel process for adding chill modeling on wax mold | |
| CN111636014A (en) | Aluminum-plastic plate aluminum base material for mahjong and manufacturing method thereof | |
| CN114515817B (en) | Casting method of large plum blossom hole frame | |
| CN110405125B (en) | Grate closed die forging process and forming closed die | |
| CN109622648B (en) | Asymmetric continuous large-deformation extrusion forming method for magnesium alloy | |
| CN104131187B (en) | A kind of aluminium alloy and preparation method thereof | |
| CN108311654B (en) | Production method for preparing thick-wall metal die by centrifugal method | |
| CN210360940U (en) | Production equipment for preventing casting from peeling | |
| CN216370059U (en) | Anti-deformation casting die for flat plate castings | |
| CN202779643U (en) | Steel-iron composite steel ingot mold | |
| CN106624617B (en) | A kind of cast aluminium alloy gold structural member forming method | |
| US2166587A (en) | Ingot mold and ingot | |
| CN110408870B (en) | Preparation method for improving coordinated rheological capacity of fine crystal layer and coarse crystal layer of gradient-structure copper alloy |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20220802 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |