CN110643841B - Method for preventing aluminum alloy cast rod from generating stress surface cracks - Google Patents
Method for preventing aluminum alloy cast rod from generating stress surface cracks Download PDFInfo
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- CN110643841B CN110643841B CN201910899917.2A CN201910899917A CN110643841B CN 110643841 B CN110643841 B CN 110643841B CN 201910899917 A CN201910899917 A CN 201910899917A CN 110643841 B CN110643841 B CN 110643841B
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- C22C1/00—Making non-ferrous alloys
- C22C1/02—Making non-ferrous alloys by melting
- C22C1/026—Alloys based on aluminium
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D7/00—Casting ingots, e.g. from ferrous metals
- B22D7/005—Casting ingots, e.g. from ferrous metals from non-ferrous metals
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C21/00—Alloys based on aluminium
- C22C21/06—Alloys based on aluminium with magnesium as the next major constituent
- C22C21/08—Alloys based on aluminium with magnesium as the next major constituent with silicon
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Abstract
The invention discloses a method for preventing an aluminum alloy cast rod from generating stress surface cracks, which comprises the following steps: s1, preparing alloy aluminum liquid: putting a proper amount of aluminum alloy cast ingots into an alloy furnace for melting, raising the temperature in the alloy furnace, melting 6061 aluminum alloy cast ingots by the alloy furnace, and heating for 20-30 min to prepare molten aluminum in the alloy furnace; s2, changing the Fe/Si ratio in the alloy components: firstly, measuring the percentage content ratio of Fe and excessive Si in the aluminum liquid, if the percentage content of Fe is detected to be lower than 0.2%, adding simple substance Fe into the alloy furnace until the percentage content of Fe is higher than 0.2%, then calculating the percentage content ratio of Fe and excessive Si, if the percentage content of Fe/excessive Si is higher than 1.417, not adding Fe into the alloy furnace, and finally changing the percentage value of Fe/Si in the alloy components; and S3, casting the aluminum alloy cast rod. The invention has the beneficial effects that: the method is favorable for reducing the generation of surface crack defects, has simple process steps, and is particularly suitable for casting the aluminum alloy cast rod.
Description
Technical Field
The invention relates to a method for preventing an aluminum alloy cast rod from generating stress surface cracks.
Background
6061 aluminum alloy is a high-quality aluminum alloy product produced by a heat treatment pre-stretching process, has the excellent characteristics of excellent processing performance, excellent weldability, electroplating property, excellent corrosion resistance, high toughness, no deformation after processing, compact and defect-free material, easiness in polishing, colored film, excellent oxidation effect and the like, and is widely applied to the fields of aerospace, rail transit, communication equipment, ships and the like. In order to pursue higher mechanical property requirements of products, various manufacturers actively explore the more appropriate alloy composition design of 6061 aluminum alloy cast rods. Practice has shown that cast rods cast from 6061 aluminum alloy exhibit a higher tendency to crack during casting than similar 6063, 6060 alloys. Unlike the common central cracks, the cracks are mainly stress surface cracks generated in the solidification and cooling process of the cast rod. For the surface cracks, if the surface cracks are not controlled and cut off in time in the casting process, the surface cracks can be further deepened and prolonged in the subsequent heat treatment process, so that products are scrapped, and great loss is brought.
Analysis of the chemical composition and related properties of 6061 shows that the 6061 alloy has a high surface crack tendency mainly due to the following three points:
1. high content of Mg2Si strengthening phase: mg (magnesium)2Si is AI-MgMain strengthening phases of Si-based alloys, calculated as alloy, Mg in 6061 alloy2The Si content is higher than that of 6063 alloy by about 50%, the strengthening phase content in the alloy is high, the strength of the cast state is increased, and meanwhile, under the unbalanced cooling condition, the strengthening phase on the grain boundary is increased, the plasticity is naturally reduced, and the crack tendency of the alloy is increased. The increase of the Mg2Si content in the alloy widens the crystallization temperature range, which increases the stress applied when crystal cracks are formed, and deteriorates the shrinkage at the end of solidification and the welding conditions, thereby increasing the crack tendency. Further, the thermal conductivity of the alloy is lowered, the liquid pocket is deepened during casting, the wall thickness of the liquid pocket is thinned, and the unit tensile stress is increased, thereby further improving the crack tendency.
2. The design of the Fe/Si ratio is not reasonable: after Si in 6061 alloy and Mg form Mg2Si phase, excessive Si forms compound with Fe and Al, and microscopic structure analysis shows that when Si is larger than Fe, the Si is mainly beta phase which is acicular and has higher brittleness, thus causing increased crack tendency.
3. Cold ingot separation with too long filling time: the surface cracks usually occur at the beginning of casting, and as is clear from observation of aluminum bars with surface cracks on site, most of the aluminum bars with surface cracks exist along with separation of cold ingots at the bar heads, and extend along with cold cracks in the radial direction, the surface of the aluminum bar at the crack extension part presents a bright line, and no cracks starting from the middle part or the tail part of the aluminum bar are found through ultrasonic flaw detection.
It was initially thought that plugging of the crystallizer water passages could cause surface crack defects due to surface stress concentrations during casting, which still occurred after all the crystallizer had been cleaned. Then, the generation of surface cracks cannot be avoided by searching and reducing the casting speed, the temperature of the molten aluminum, the speed of the titanium boron wire and the like. Therefore, a method for preventing the generation of stress surface cracks during casting is needed.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a method for preventing an aluminum alloy cast rod from generating stress surface cracks, which is beneficial to reducing the generation of surface crack defects, has simple process steps and is particularly suitable for casting the aluminum alloy cast rod.
The purpose of the invention is realized by the following technical scheme: a method for preventing stress surface cracks from being generated on an aluminum alloy cast rod comprises the following steps:
s1, preparing alloy aluminum liquid: putting a proper amount of aluminum alloy cast ingots into an alloy furnace for melting, raising the temperature in the alloy furnace, melting 6061 aluminum alloy cast ingots by the alloy furnace, and heating for 20-30 min to prepare molten aluminum in the alloy furnace;
s2, changing the Fe/Si ratio in the alloy components:
firstly, measuring the percentage content ratio of Fe and excessive Si in the aluminum liquid, if the percentage content of Fe is detected to be lower than 0.2%, adding simple substance Fe into the alloy furnace until the percentage content of Fe is higher than 0.2%, then calculating the percentage content ratio of Fe and excessive Si, if the percentage content of Fe/excessive Si is higher than 1.417, not adding Fe into the alloy furnace, and finally changing the percentage value of Fe/Si in the alloy components;
s3, casting the aluminum alloy cast rod, which comprises the following steps:
s31, blocking the runner in front of a casting die of the casting machine by a plurality of baffle plates in sections, and filling the molten aluminum in the alloy furnace into each section of runner;
s32, heating the temperatures of the die disc and the launder until the temperatures of the die disc and the launder reach 150-160 ℃;
s33, setting the parameters of the casting machine as a casting speed of 63-127 mm/min, a casting flow port temperature of 704-714 ℃, a casting mold front end temperature of 689-698 ℃, a casting mold rear end temperature of 686-695 ℃, a casting water temperature of 27.5-29 ℃ and a cooling water flow rate of 250-470 m3/h；
And S34, filling the aluminum liquid in the launder into the casting cavity of the casting machine within 12-15S, and opening the casting machine after 15-25 min to take the cast and molded product out of the casting cavity.
And in the step S34, the product is cooled in air.
The casting cavity in the step S34 is hollow cylindrical.
The invention has the following advantages: (1) the invention changes the Fe/Si ratio in the alloy components, and reduces the crack tendency of the cast rod when Fe is larger than Si, thereby ensuring that no crack is generated on the cast rod. (2) The invention achieves the purposes of reducing the temperature drop of the filled aluminum liquid as much as possible and slowing down the separation of cold ingots by shortening the filling time, fully preheating the flow groove and improving the liquid level of the flow groove in the filling process, thereby greatly facilitating the reduction of the generation of surface crack defects and further ensuring that no cracks are generated on the cast rod.
Drawings
FIG. 1 is a graph showing the number of cracks in a cast rod cast with molten aluminum having different Fe/excess Si ratios.
Detailed Description
The invention will be further described with reference to the accompanying drawings, without limiting the scope of the invention to the following:
the first embodiment is as follows: a method for preventing stress surface cracks from being generated on an aluminum alloy cast rod comprises the following steps:
s1, preparing alloy aluminum liquid: putting a proper amount of aluminum alloy cast ingots into an alloy furnace for melting, raising the temperature in the alloy furnace, melting 6061 aluminum alloy cast ingots by the alloy furnace, and heating for 20min to prepare aluminum liquid in the alloy furnace;
s2, changing the Fe/Si ratio in the alloy components:
firstly, measuring the percentage content ratio of Fe and excessive Si in the aluminum liquid, if the percentage content of Fe is detected to be lower than 0.2%, adding simple substance Fe into the alloy furnace until the percentage content of Fe is higher than 0.2%, then calculating the percentage content ratio of Fe and excessive Si, if the percentage content of Fe/excessive Si is higher than 1.417, not adding Fe into the alloy furnace, and finally changing the percentage value of Fe/Si in the alloy components; because the content of Fe is higher than that of Si, an alpha phase is mainly formed, and the alpha phase is skeleton-shaped and has small brittleness; and when Fe > Si in the alloy, the crystallization process is finished in a peritectic transformation mode at 611 ℃, and when Fe < Si, the crystallization process of the alloy is finished in a eutectic transformation mode at 577 ℃, compared with the former, the effective crystallization temperature range is shortened by 34 ℃, the hot brittleness of the alloy is reduced, so that the cracking tendency of the cast rod is reduced when Fe > Si is ensured, and no crack is generated on the cast rod; as shown in FIG. 1, the number of cracks on a cast rod cast by aluminum liquid with different Fe/excess Si ratios is shown, and it can be seen that no surface crack defect is found when the Fe/excess Si ratio is more than 1.417.
S3, casting the aluminum alloy cast rod, which comprises the following steps:
s31, blocking the runner in front of a casting die of the casting machine by a plurality of baffle plates in sections, and filling the molten aluminum in the alloy furnace into each section of runner;
s32, heating the temperatures of the die disc and the launder until the temperatures of the die disc and the launder reach 150-160 ℃;
s33, setting the parameters of the casting machine as a casting speed of 63mm/min, a casting runner temperature of 704 ℃, a casting mold front end temperature of 689 ℃, a casting mold rear end temperature of 686 ℃, a casting water temperature of 27.5 ℃ and a cooling water flow rate of 250m3/h；
And S34, filling the molten aluminum in the launder into a casting cavity of a casting machine within 12S, wherein the casting cavity is hollow cylindrical, opening the casting machine after 15min, taking out the cast and molded product from the casting cavity, and cooling the product in air.
In step S3, the temperature drop of the filled aluminum liquid is reduced as much as possible and the cold ingot separation is slowed down by shortening the filling time, fully preheating the runner and increasing the liquid level of the runner in the filling process, thereby greatly facilitating the reduction of the surface crack defects and further ensuring that no cracks are generated on the cast rod.
Example two: a method for preventing stress surface cracks from being generated on an aluminum alloy cast rod comprises the following steps:
s1, preparing alloy aluminum liquid: putting a proper amount of aluminum alloy cast ingots into an alloy furnace for melting, raising the temperature in the alloy furnace, melting 6061 aluminum alloy cast ingots by the alloy furnace, and heating for 25min to prepare aluminum liquid in the alloy furnace;
s2, changing the Fe/Si ratio in the alloy components:
firstly, measuring the percentage content ratio of Fe and excessive Si in the aluminum liquid, if the percentage content of Fe is detected to be lower than 0.2%, adding simple substance Fe into the alloy furnace until the percentage content of Fe is higher than 0.2%, then calculating the percentage content ratio of Fe and excessive Si, if the percentage content of Fe/excessive Si is higher than 1.417, not adding Fe into the alloy furnace, and finally changing the percentage value of Fe/Si in the alloy components;
s3, casting the aluminum alloy cast rod, which comprises the following steps:
s31, blocking the runner in front of a casting die of the casting machine by a plurality of baffle plates in sections, and filling the molten aluminum in the alloy furnace into each section of runner, thereby improving the liquid level of the runner in the filling process;
s32, heating the temperatures of the die plate and the launder until the temperatures of the die plate and the launder reach 155 ℃;
s33, setting the parameters of the casting machine as casting speed 100mm/min, casting flow port temperature 710 ℃, casting front end temperature 694 ℃, casting rear end temperature 694 ℃, casting water temperature 28 ℃ and cooling water flow 300m3/h；
And S34, filling the molten aluminum in the launder into a casting cavity of a casting machine within 13S, wherein the casting cavity is hollow cylindrical, and opening the casting machine after 20min to take out the cast and molded product from the casting cavity and air-cooling the product.
Example three: a method for preventing stress surface cracks from being generated on an aluminum alloy cast rod comprises the following steps:
s1, preparing alloy aluminum liquid: putting a proper amount of aluminum alloy cast ingots into an alloy furnace for melting, raising the temperature in the alloy furnace, melting 6061 aluminum alloy cast ingots by the alloy furnace, and heating for 30min to prepare aluminum liquid in the alloy furnace;
s2, changing the Fe/Si ratio in the alloy components:
firstly, measuring the percentage content ratio of Fe and excessive Si in the aluminum liquid, if the percentage content of Fe is detected to be lower than 0.2%, adding simple substance Fe into the alloy furnace until the percentage content of Fe is higher than 0.2%, then calculating the percentage content ratio of Fe and excessive Si, if the percentage content of Fe/excessive Si is higher than 1.417, not adding Fe into the alloy furnace, and finally changing the percentage value of Fe/Si in the alloy components;
s3, casting the aluminum alloy cast rod, which comprises the following steps:
s31, blocking the runner in front of a casting die of the casting machine by a plurality of baffle plates in sections, and filling the molten aluminum in the alloy furnace into each section of runner;
s32, heating the temperatures of the die plate and the launder until the temperatures of the die plate and the launder reach 160 ℃;
s33, setting the parameters of the casting machine as casting speed 127mm/min, casting spout temperature 714 deg.C, casting front end temperature 698 deg.C, casting rear end temperature 695 deg.C, casting water temperature 29 deg.C and cooling water flow 470m3/h；
And S34, filling the molten aluminum in the launder into a casting cavity of a casting machine within 15S, wherein the casting cavity is hollow cylindrical, opening the casting machine after 25min to take out the cast and molded product from the casting cavity, and cooling the product in air.
Claims (3)
1. A method for preventing an aluminum alloy cast rod from generating stress surface cracks is characterized by comprising the following steps: it comprises the following steps:
s1, preparing alloy aluminum liquid: putting a proper amount of aluminum alloy cast ingots into an alloy furnace for melting, raising the temperature in the alloy furnace, melting 6061 aluminum alloy cast ingots by the alloy furnace, and heating for 20-30 min to prepare molten aluminum in the alloy furnace;
s2, changing the Fe/Si ratio in the alloy components:
firstly, measuring the percentage content ratio of Fe and excessive Si in the aluminum liquid, if the percentage content of Fe is detected to be lower than 0.2%, adding simple substance Fe into the alloy furnace until the percentage content of Fe is higher than 0.2%, then calculating the percentage content ratio of Fe and excessive Si, if the percentage content of Fe/excessive Si is higher than 1.417, not adding Fe into the alloy furnace, and finally changing the percentage value of Fe/Si in the alloy components;
s3, casting the aluminum alloy cast rod, which comprises the following steps:
s31, heating the temperatures of the die disc and the launder until the temperatures of the die disc and the launder reach 150-160 ℃;
s32, setting the parameters of the casting machine as a casting speed of 63-127 mm/min, a casting flow port temperature of 704-714 ℃, a casting mold front end temperature of 689-698 ℃, a casting mold rear end temperature of 686-695 ℃, a casting water temperature of 27.5-29 ℃ and a cooling water flow rate of 250-470 m3/h；
S33, blocking the runner in front of a casting die of the casting machine by a plurality of baffle plates in sections, and filling the molten aluminum in the alloy furnace into each section of runner;
and S34, filling the aluminum liquid in the launder into the casting cavity of the casting machine within 12-15S, and opening the casting machine after 15-25 min to take the cast and molded product out of the casting cavity.
2. The method of preventing stress surface cracking in an aluminum alloy cast bar according to claim 1, wherein: and in the step S34, the product is cooled in air.
3. The method of preventing stress surface cracking in an aluminum alloy cast bar according to claim 1, wherein: the casting cavity in the step S34 is hollow cylindrical.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103205610A (en) * | 2013-03-27 | 2013-07-17 | 成都阳光铝制品有限公司 | 6A02 aluminum alloy round ingot and production process thereof |
| CN104109784A (en) * | 2014-04-30 | 2014-10-22 | 广西南南铝加工有限公司 | Ultrahigh-strength Al-Zn-Mg-Cu system aluminum alloy large-size flat cast ingot and making method thereof |
| CN106521264A (en) * | 2016-11-10 | 2017-03-22 | 广西大学 | Fusion casting technology for aluminum alloy flat ingot for packaging tin |
| WO2018169766A3 (en) * | 2015-12-04 | 2018-11-01 | Raytheon Company | Composition and method for fusion processing aluminum alloy |
| CN109468502A (en) * | 2018-12-06 | 2019-03-15 | 广东省材料与加工研究所 | A kind of Aluminum alloy extrusion material and its manufacturing method of shock resistance energy absorption characteristics |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103205610A (en) * | 2013-03-27 | 2013-07-17 | 成都阳光铝制品有限公司 | 6A02 aluminum alloy round ingot and production process thereof |
| CN104109784A (en) * | 2014-04-30 | 2014-10-22 | 广西南南铝加工有限公司 | Ultrahigh-strength Al-Zn-Mg-Cu system aluminum alloy large-size flat cast ingot and making method thereof |
| WO2018169766A3 (en) * | 2015-12-04 | 2018-11-01 | Raytheon Company | Composition and method for fusion processing aluminum alloy |
| CN106521264A (en) * | 2016-11-10 | 2017-03-22 | 广西大学 | Fusion casting technology for aluminum alloy flat ingot for packaging tin |
| CN109468502A (en) * | 2018-12-06 | 2019-03-15 | 广东省材料与加工研究所 | A kind of Aluminum alloy extrusion material and its manufacturing method of shock resistance energy absorption characteristics |
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