阅读说明：本技术 新能源汽车用液冷电机壳挤压铝型材及其加工工艺 (Extruded aluminum profile of liquid cooling motor casing for new energy automobile and processing technology thereof ) 是由 杨立峰 于 2020-11-18 设计创作，主要内容包括：本发明公开了一种新能源汽车用液冷电机壳挤压铝型材,其成分配比如下：Mg：0.55％-0.60％；Si：0.45％-0.50％；Mg：Si＝1.2-1.30；Fe＜0.10％-0.20％；Mn、Cr、Zn三者的总占比＜0.05％。本发明制备的型材出料稳定、平直,产品尺寸符合图纸要求,弯曲、扭拧度符合图纸要求,产品轮廓度检测符合检具要求。从铸锭开始加热到挤压型材的淬火都能保证可溶解的相组织不从固溶中析出或呈现小颗粒的弥散析出。变形热效应、变形均匀性、再结晶和固溶过程、制品力学性能及制品表面质量均有很大提升。制品表面未出现麻点、裂纹等倾向。金属变形的不均匀性几乎没有。(The invention discloses a liquid cooling motor shell extruded aluminum profile for a new energy automobile, which comprises the following components in parts by weight: mg: 0.55% -0.60%; si: 0.45% -0.50%; mg: si is 1.2-1.30; fe is less than 0.10 to 0.20 percent; the total ratio of Mn, Cr and Zn is less than 0.05 percent. The section bar prepared by the invention has stable and straight discharging, the product size meets the drawing requirements, the bending and twisting degrees meet the drawing requirements, and the product profile detection meets the requirements of a detection tool. The heating from the ingot to the quenching of the extruded section can ensure that soluble phase structures are not separated from solid solution or dispersed and separated out of small particles. The deformation heat effect, the deformation uniformity, the recrystallization and solid solution processes, the mechanical property of the product and the surface quality of the product are all greatly improved. The surface of the product has no tendency of pocking marks, cracks and the like. The unevenness of the metal deformation is almost none.)

1. Liquid cooling motor casing extrusion aluminium alloy for new energy automobile, its characterized in that, its composition ratio of aluminium alloy is as follows: mg: 0.55% -0.60%; si: 0.45% -0.50%; mg: si is 1.2-1.30; fe is less than 0.10 to 0.20 percent; the total ratio of Mn, Cr and Zn is less than 0.05 percent.

2. The process for processing the extruded aluminum profile of the liquid-cooled motor shell for the new energy automobile as claimed in claim 1 is characterized by comprising the following steps of: mold design → mold processing and manufacturing → alloy composition determination → cast rod → test mold → size inspection → extrusion production → online quenching → stretching and straightening → size inspection → sawing and framing → artificial aging → mechanical property inspection → fine sawing → finished product inspection and packaging → warehousing.

3. The processing technology of the extruded aluminum profile of the liquid cooling motor casing for the new energy automobile as claimed in claim 2, wherein in the extrusion production process, the temperature of an extrusion cylinder is 420-; temperature of the aluminum bar: 490-540 ℃, considering the complicated structure of the section bar, the extrusion speed should be selected to be slow, the extrusion speed is more than or equal to 4.0-5.0m/min according to the metal outflow speed, and the outlet temperature is controlled between 510-540 ℃; adopting an on-line quenching and strong wind cooling mode, wherein the cooling speed is more than or equal to 200 ℃/min, and the quenching temperature is less than or equal to 250 ℃; the stretching ratio is 0.3 to 0.5 percent.

4. The processing technology of the extruded aluminum profile of the liquid cooling motor shell for the new energy automobile is characterized in that in the artificial aging process, the aging temperature is 185 ℃, the temperature is kept for 6 hours, the aluminum profile is discharged from the furnace and cooled by strong wind, and the cooling speed is 200 ℃/min.

5. The extrusion die for processing the extruded aluminum profile of the liquid cooling motor shell for the new energy automobile as claimed in claim 1, is characterized by comprising an upper die and a lower die, wherein the upper die is provided with a plurality of flow guide holes, the lower die is provided with a plurality of flow distribution holes communicated with the flow guide holes, and a die core of the lower die is composed of a large-size die and a small-size die embedded in a central hole of the large-size die.

6. The extrusion die for the liquid-cooled motor shell extruded aluminum profile for the new energy automobile as claimed in claim 5, wherein the lower die is provided with an embedding hole for large-size die hot interference, and the shunting hole is formed around the embedding hole; the size of each diversion hole is larger than that of each diversion hole, adjacent diversion holes are connected through a pressure reducing bridge, a flow passage hole is formed in the lower surface of the pressure reducing bridge, and a lower die lug for forming a water passage is arranged on the lower die at the position of each diversion hole.

7. The extrusion die for the extruded aluminum profile of the liquid-cooled motor shell for the new energy automobile as claimed in claim 6, wherein the large-size die is in a frustum shape, a central hole is formed in the center of the large-size die, the central hole is in a stepped hole shape, and the small-size die is in a stepped column shape matched with the stepped hole; the upper die and the lower die are detachably connected through bolts.

8. The extrusion die for the extruded aluminum profile of the liquid-cooled motor shell for the new energy automobile as claimed in claim 7, wherein the maximum outer diameter of the large-size die is 197mm, and the diameter of the large-size hole of the stepped hole is 110 mm; the core material shown is H13 forged steel.

9. The extrusion die of the extruded aluminum profile of the liquid-cooled motor shell for the new energy automobile as claimed in claim 8, wherein the flow guide hole is in a shape of a tapered hole with a large upper part and a small lower part.

Technical Field

The invention relates to an extruded aluminum profile of a liquid cooling motor shell for a new energy automobile and a processing technology thereof.

Background

Along with the global popularization of light weight automobiles and green new energy electric automobiles, a plurality of countries correspondingly set up a policy of supporting new energy automobiles and the forbidden sale period of fuel oil automobiles, the amount of aluminum for automobiles is also continuously increased, the original single engine and skylight use aluminum alloy, and a plurality of parts are also changed from steel materials to use aluminum alloy or steel-aluminum composite materials, such as green new energy battery trays, battery packs, automobile motor shells, automobile front and rear bumpers, automobile frames and the like, and even some international high-end automobile types are changed to use all-aluminum automobile bodies.

The liquid cooling motor casing section bar for the new energy automobile is characterized in that an alloy state is 6063-T6, a cross section is shown in figure 1, the section bar is large in section, the thickness of a circumscribed circle wall is 264mm, the meter weight reaches 36.8kg/m, the extrusion ratio is small, lambda is 7.7, and the mechanical property meets the standard requirement of GB/T6892-2015;

from the cross-sectional analysis, there are the following difficulties:

1. the shape of the motor casing is a circular section bar diagram, and the inner hole of the motor casing isThe hole is totally 11 water courses 10 all around, and the water course width is only 7.0mm, and the mold core size is little, and easy beat, the wall thickness is uneven, has certain influence to mould ejection of compact stability, if it is serious to incline the jade or jade, can lead to follow-up processing water course end cover unable processing when hole and appear the condemned risk of product. Therefore, certain requirements are required for the size and position of the water channel holes. From the analysis of product section, the prerequisite that product extrusion ejection of compact size is stable is that every detail of the processing of mould must target in place, and the flow of every water conservancy diversion hole, the blank size of guide chute, mold core need be even unanimous, and the hardness after the mould heat treatment also needs to be even, and traditional mould manufacturing process must can't satisfy above requirement yet, mainly embodies following several:

(1) the large mold core in the middle is large and reaches 197mm, and the hardness of the mold after heat treatment has uneven risk;

(2) the periphery of the large mold core is surrounded by 11 small mold cores, the size of each small mold core is only 7 x 53.95, when the hollow cutter and the drainage groove of the mold core are machined, the small mold core can be corroded little by electric sparks, the electrode position used by the electric sparks is generally observed by workers according to experience and naked eyes, the phenomena of insufficient and uneven machining and electric spark corrosion of pits and uneven surfaces are determined, if the hollow cutter position and the drainage groove are not machined, the section extrusion feeding is insufficient, if the machining is excessive, the flow is overlarge during section extrusion, the discharge of the section is unstable when the section is extruded from the mold, the small mold core swings obliquely, the discharge of the section is oblique, the mold is scrapped seriously, the machining time of the electric spark machining is long, and the progress of the mold is severely restricted.

The material is in a 6063-T6 alloy state, in order to ensure the outlet temperature of the material and ensure the alloy to be fully dissolved, and in order to ensure the mechanical property of the material, a proper extrusion ratio is needed, the model is 6800T, but the extrusion ratio is still small, only lambda is 7.7, and the reasonable extrusion ratio is 15-35 to be optimal. In addition, in order to obtain higher mechanical properties, a quenching mode generally selects strong wind and water mist, and the product is subjected to cross section analysis, if the product is quenched by using water or the water mist mode, the product is seriously deformed, bent and twisted during discharging, if the product is cooled unevenly, an inner hole is elliptical, the size is poor, and the production difficulty of the product is increased, so that the quenching mode only can be cooling by strong wind, but the air cooling can certainly not cool enough, and the risk that the alloy cannot be fully dissolved is caused.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide the liquid cooling motor shell extruded aluminum profile for the new energy automobile, the prepared profile is stable and straight in discharging, the product size meets the drawing requirements, the bending and twisting degrees meet the drawing requirements, and the product profile detection meets the requirements of a detection tool.

In order to achieve the purpose, the technical scheme of the invention is to design a liquid cooling motor shell extruded aluminum profile for a new energy automobile, which comprises the following components in parts by weight: mg: 0.55% -0.60%; si: 0.45% -0.50%; mg: si is 1.2-1.30; fe is less than 0.10 to 0.20 percent; the total ratio of Mn, Cr and Zn is less than 0.05 percent. The 6063-T6 aluminum profile has certain mechanical property. The tensile strength and yield strength of the alloy are increased along with the increase of the content under the same other conditions. 6063 the strengthening phase of the platinum is mainly the Mg2Si phase, the Mg2Si phase is composed of 2 Mg atoms and 1 si atom, the relative atomic mass of Mg is 24.3l, and the relative atomic mass of si is 28.09, so in the M g2Si compound, the mass ratio of Mg to si is 1.73: 1. according to the above analysis results, if the ratio of Mg to Si content is greater than 1.73, Mg in the alloy forms an excess of Mg in addition to the Mg2Si phase, whereas if the ratio is less than 1.73, Si forms an excess of Si in addition to the Mg2Si phase. Excess magnesium is detrimental to the mechanical properties of the alloy. Magnesium is generally controlled to be about 0.5 percent, and the total amount of Mg2Si is controlled to be 0.79 percent. When the silicon is excessive by 0.01 percent, the mechanical property sigma b of the alloy is about 218Mpa, which greatly exceeds the national standard performance, the excessive silicon is improved from 0.01 percent to 0.13 percent, and the tensile strength can be improved to about 250Mpa, namely improved by 14.6 percent. To form a certain amount of Mg2Si, it is necessary to first consider the silicon loss due to the content of impurities such as Fe and Mn, i.e. to ensure a certain amount of excess silicon. In order to make the magnesium in the 6063 alloy sufficiently match with silicon, in actual batching, it is necessary to consciously make the ratio of Mg: si is less than 1.73. The excess of magnesium not only weakens the strengthening effect but also increases the product cost.

The invention also provides a technical scheme that the process for processing the liquid cooling motor shell extruded aluminum profile for the new energy automobile comprises the following working procedures: mold design → mold processing and manufacturing → alloy composition determination → cast rod → test mold → size inspection → extrusion production → online quenching → stretching and straightening → size inspection → sawing and framing → artificial aging → mechanical property inspection → fine sawing → finished product inspection and packaging → warehousing. Of course, in actual production, the process steps are adapted as adjustments in consideration of the requirements of customers, as follows: mold design → mold processing and manufacturing → alloy composition determination → casting rod → trial mold → dimensional inspection → customer sample presentation → customer confirmation → extrusion small batch production → online quenching → stretch straightening → dimensional inspection → sawing framing → artificial aging → mechanical property inspection → fine sawing → finished product inspection and packaging → warehousing → customer confirmation → batch production. 1. Designing and manufacturing a mould;

2. testing mold → repairing mold → testing mold → size is qualified, according to each testing mold result, reasonably adjusting the flow velocity and flow rate of each part of the mold, and repairing mold until the discharging size is qualified;

3. formulating a reasonable extrusion process;

4. formulating a reasonable aging process;

5. and optimizing the design scheme of the die according to the die testing result of the first set of die, and ensuring the qualification rate of the die testing on the subsequent die.

In the aspect of mold design, the traditional mold design concept is changed mainly from the direction of how to increase the strength of the mold and improve the machining precision of the mold, the large mold core is changed into an embedding method, and the large mold core is changed into an embedding methodThe small mold core (the large mold core is embedded by adopting a thermal interference method after finish turning of heat treatment), the space between the mold core and the mold core is provided, a plurality of original procedures needing electric spark machining are changed into numerical control machine tool machining, the machining precision and the mold strength of the mold are improved, the machining and manufacturing time of the mold is greatly shortened, and the technical problem of uneven heat treatment hardness caused by overlarge mold core is solved; the steel material is selected from high-strength H13 forged steel material with more reliable quality (the proportion of metal elements Mo and Vi of the steel material is properly adjusted by negotiation with a steel material supplier), after the heat treatment of the die, the hardness of the upper die is controlled to be 48-50HRC, and the hardness of the lower die is controlled to be 50-52 HRC.

The further technical scheme is that in the extrusion production process, the temperature of an extrusion cylinder is 420-430 ℃, the temperature of a die is 480-500 ℃, and the temperature is kept for 4-6 h; temperature of the aluminum bar: 490-540 ℃, considering the complicated structure of the section bar, the extrusion speed should be selected to be slow, the extrusion speed is more than or equal to 4.0-5.0m/min according to the metal outflow speed, and the outlet temperature is controlled between 510-540 ℃; adopting an on-line quenching and strong wind cooling mode, wherein the cooling speed is more than or equal to 200 ℃/min, and the quenching temperature is less than or equal to 250 ℃; the stretching ratio is 0.3 to 0.5 percent.

The further technical scheme is that in the artificial aging process, the aging temperature is 185 ℃, the temperature is kept for 6h, the steel is taken out of the furnace and cooled by strong wind, and the cooling speed is 200 ℃/min.

The invention also provides a technical scheme that the extrusion die for processing the liquid cooling motor shell extruded aluminum profile for the new energy automobile comprises an upper die and a lower die, wherein the upper die is provided with a plurality of flow guide holes, the lower die is provided with a plurality of flow distribution holes communicated with the flow guide holes, and a die core of the lower die consists of a large-size die and a small-size die embedded in a central hole of the large-size die. Extrusion temperature is the most fundamental and critical process factor for extrusion production. The extrusion temperature has a great influence on product quality, production efficiency, die life, energy consumption, etc. The most important problem of extrusion is the control of the metal temperature, and the soluble phase structure is not separated from solid solution or dispersed small particles are separated from the solid solution from the beginning of heating the cast ingot to quenching the extruded section. The extrusion speed must be carefully controlled during the extrusion process. The extrusion speed has important influence on the deformation heat effect, the deformation uniformity, the recrystallization and solid solution processes, the mechanical property of the product and the surface quality of the product. The extrusion speed is too high, so that pockmarks, cracks and the like tend to appear on the surface of the product. Meanwhile, the extrusion speed is too high, so that the nonuniformity of metal deformation is increased. The outflow rate during extrusion depends on the type of alloy and the geometry, dimensions and surface conditions of the profile.

The further technical scheme is that the lower die is provided with a large-size die thermal interference embedding hole, and the shunting hole is arranged around the embedding hole; the size of each diversion hole is larger than that of each diversion hole, adjacent diversion holes are connected through a pressure reducing bridge, a flow passage hole is formed in the lower surface of the pressure reducing bridge, and a lower die lug for forming a water passage is arranged on the lower die at the position of each diversion hole. The lower die convex block can be realized by integrally connecting the lower die convex block on the upper die, namely the lower surface of the upper die is integrally connected with the lower die convex block which protrudes downwards.

The large-size die is in a frustum shape, a center hole is formed in the center of the large-size die, the center hole is in a stepped hole shape, and the small-size die is in a stepped column shape matched with the stepped hole; the upper die and the lower die are detachably connected through bolts.

The further technical scheme is that the maximum outer diameter of the large-size die is 197mm, and the aperture of the large-size hole of the stepped hole is 110 mm; the core material shown is H13 forged steel.

The further technical proposal is that the diversion hole is in a tapered hole shape with a big top and a small bottom. Therefore, the principle of fluid mechanics is utilized during extrusion, the extruded aluminum profile on the lower die can be more sufficient, and the condition of thin wall or inclined wall is avoided.

The invention has the advantages and beneficial effects that: the prepared section bar isThe material is stable and straight, the product size meets the requirement of a drawing, the bending degree and the twisting degree meet the requirement of the drawing, and the product profile detection meets the requirement of a checking fixture. The heating from the ingot to the quenching of the extruded section can ensure that soluble phase structures are not separated from solid solution or dispersed and separated out of small particles. The deformation heat effect, the deformation uniformity, the recrystallization and solid solution processes, the mechanical property of the product and the surface quality of the product are all greatly improved. The surface of the product has no tendency of pocking marks, cracks and the like. The unevenness of the metal deformation is almost none. The traditional die design concept is changed, the large die core is changed into an embedding method, and the large die core is changed into an embedding methodThe small mold core (the large mold core is embedded by adopting a thermal interference method after finish turning of heat treatment) gives a space between the mold core and the mold core<Refers to the space between the large-size die and the lower die lug>A plurality of original procedures needing electric spark machining are changed into numerical control machine tool machining, so that the machining precision and the die strength of the die are improved, the machining and manufacturing time of the die is greatly shortened, and the technical problem of uneven heat treatment hardness caused by overlarge die core is solved; the strength of the die is improved, and the machining precision of the die is improved. And the principle of hydromechanics is utilized during extrusion, so that the extruded aluminum profile on the lower die can be more sufficient, and the condition of thin wall or inclined wall is avoided.

Drawings

FIG. 1 is a schematic diagram of a liquid cooling motor shell extruded aluminum profile for a new energy automobile;

FIG. 2 is a schematic view of an extrusion die to which the present invention relates;

FIG. 3 is a longitudinal section through the bolt in FIG. 2;

FIG. 4 is an exploded view of the large size mold and the lower size mold of the lower mold after the mold closing of the present invention.

In the figure: 1. an upper die; 2. a lower die; 3. a flow guide hole; 4. a shunt hole; 5. a large-size die; 6. a small-sized die; 7. embedding holes; 8. a pressure reducing bridge; 9. a flow passage hole; 10. a water channel; 11. A bump; 12. a central bore; 13. and (4) bolts.

Detailed Description

The following description of the embodiments of the present invention will be made with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

As shown in fig. 2 to 4, the invention relates to a liquid cooling motor shell extruded aluminum profile for a new energy automobile, which comprises the following components in parts by weight: mg: 0.55% -0.60%; si: 0.45% -0.50%; mg: si is 1.2-1.30; fe is less than 0.10 to 0.20 percent; the total ratio of Mn, Cr and Zn is less than 0.05 percent.

The process for processing the liquid cooling motor shell extruded aluminum profile for the new energy automobile comprises the following steps of: mold design → mold processing and manufacturing → alloy composition determination → cast rod → test mold → size inspection → extrusion production → online quenching → stretching and straightening → size inspection → sawing and framing → artificial aging → mechanical property inspection → fine sawing → finished product inspection and packaging → warehousing. In the extrusion production process, the temperature of an extrusion cylinder is 420-430 ℃, the temperature of a die is 480-500 ℃, and the temperature is kept for 4-6 h; temperature of the aluminum bar: 490-540 ℃, considering the complicated structure of the section bar, the extrusion speed should be selected to be slow, the extrusion speed is more than or equal to 4.0-5.0m/min according to the metal outflow speed, and the outlet temperature is controlled between 510-540 ℃; adopting an on-line quenching and strong wind cooling mode, wherein the cooling speed is more than or equal to 200 ℃/min, and the quenching temperature is less than or equal to 250 ℃; the stretching ratio is 0.3 to 0.5 percent. In the artificial aging process, the aging temperature is 185 ℃, the temperature is kept for 6h, and the steel is discharged from the furnace and cooled by strong wind, wherein the cooling speed is 200 ℃/min.

The related extrusion die, as shown in fig. 2 to 4, comprises an upper die 1 and a lower die 2, wherein the upper die 1 is provided with a plurality of diversion holes 3, the lower die 2 is provided with a plurality of diversion holes 4 communicated with the diversion holes 3, and a die core of the lower die 2 comprises a large-size die 5 and a small-size die 6 embedded in a central hole 12 of the large-size die 5. The lower die 2 is provided with an embedding hole 7 for hot interference of the large-size die 5, and the shunting hole 4 is arranged around the embedding hole 7; the diversion holes 3 are larger than the diversion holes 4 in size, the adjacent diversion holes 4 are connected through the decompression bridge 8, the lower surface of the decompression bridge 8 is provided with a flow passage hole 9, and the lower die 2 at the position of the diversion hole 4 is provided with a lower die 2 lug 11 for forming a water channel 10. The center of the large-size die 5 is provided with a central hole 12, the central hole 12 is a stepped hole, and the small-size die 6 is in a stepped column shape matched with the stepped hole; the upper die 1 and the lower die 2 are detachably connected through bolts 13. The maximum outer diameter of the large-size die 5 is 197mm, and the aperture of the large-size hole of the stepped hole is 110 mm; the core material shown is H13 forged steel. The diversion holes 3 are in the shape of conical holes with large upper parts and small lower parts.

The mechanical properties are measured as follows:

the sales volume of the aluminum alloy section bar of the automobile liquid cooling motor shell prepared by the scheme of the invention reaches 50-100 tons/month, and the aluminum alloy section bar has stable size and performance.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the technical principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.