Casting and forging process for aluminum alloy forging of new energy vehicle

Abstract

Disclosed in the present invention is a casting and forging process for an aluminum alloy forging of a new energy vehicle. The casting and forging process comprises: smelting an aluminum ingot; and casting and preforming the smelted aluminum ingot to form a blank; homogenizing the blank; carrying out inspection before cutting; performing pre-forging and final forging after heating; performing edge cutting treatment after water cooling; performing heat treatment; performing flaw detection and shot blasting treatment after cleaning; and finally performing inspection and warehousing. The problems of difficulties in forming in the existing casting and forging process, and a high rejection rate in a manufacturing process which makes normal batch production impossible are solved.

Description

Casting and forging technology of aluminum alloy forgings for new energy vehicles Technical Field

[0001] The present invention relates to a casting and forging process for forgings, and in particular to a casting and forging process for aluminum alloy forgings for new energy vehicles. Background Art

[0002] New energy vehicles often require the use of many aluminum alloy forgings. In its casting and forging process, the conventional casting and forging process includes aluminum ingot melting - casting round ingots - homogenization - inspection - heating - extrusion of bars - heat treatment - inspection - transportation - sawing - heating - roll forging - bending - forging (pre-forging) - heating - forging (final forging) - trimming - air cooling - heat treatment - cleaning - flaw detection - shot blasting - inspection - warehousing. For some parts with high complexity, such as forks, high ribs, deep cavities, etc., conventional forging processes are difficult to form, the scrap rate in the manufacturing process is high, and mass production cannot be achieved normally.

[0003] Therefore, it is an urgent problem to be solved by the present invention to provide a casting and forging process for aluminum alloy forgings for new energy vehicles with a shorter process flow, lower casting and forging costs, and the ability to meet mass production and stable production quality.

[0004] Summary of the Invention

[0005] The purpose of the present invention is to provide a casting and forging process for aluminum alloy forgings for new energy vehicles, which solves the problems of difficult molding in existing casting and forging processes, high scrap rate in the manufacturing process, and inability to achieve normal mass production.

[0006] In order to achieve the above-mentioned objectives, the present invention provides a casting and forging process for aluminum alloy forgings for new energy vehicles, the casting and forging process comprising: smelting aluminum ingots; pre-casting the smelted aluminum ingots to form a blank; homogenizing the blank; cutting it after inspection; performing pre-forging and final forging after heating; trimming after water cooling; heat treatment; flaw detection and shot blasting after cleaning; and finally inspection and storage.

[0007] Preferably, the smelting step includes: heating the aluminum ingot to 800-900° C., keeping the temperature for 30-40 minutes, lowering the temperature to 500-600° C., keeping the temperature for 20-30 minutes, and then casting the ingot into a mold for pre-forming.

[0008] Preferably, the heating rate is 4-6°C / min, and the cooling rate is 1-3°C / min.

[0009] Preferably, in the steps, the homogenization treatment is three step-by-step temperature increase treatments;

[0010] Including: the temperature of the first stage homogenization treatment is 350-460℃, and the holding time is 2-4h;

[0011] The temperature of the second stage homogenization treatment is 480-510℃, and the holding time is 3-6h;

[0012] The temperature of the third stage homogenization treatment is 500-650℃, and the holding time is 10-12h.

[0013] Preferably, in the step, the heat treatment conditions include: a temperature of 400-550° C. and a time of 40-50 min.

[0014] Preferably, the aluminum ingot comprises the following composition: 0.035-0.1% Cu, 1.14-1.35% Si, 0.201-0.32% Fe, 0.65-0.82% Mn, 0.13-0.82% Mg, 0.015-0.045% Ti, 0.02-0.065% Zn, 0.13-0.85% Cr and the balance Al.

[0015] The present invention provides a casting and forging process for aluminum alloy forgings for new energy vehicles, the casting and forging process comprising: smelting aluminum ingots; pre-casting the smelted aluminum ingots to form a blank; homogenizing the blank; cutting after inspection; pre-forging and final forging after heating; trimming after water cooling; heat treatment; flaw detection and shot blasting after cleaning; and finally inspection and storage. Compared with traditional forging processes, the casting and forging process provided by the present invention has a shorter process flow and requires less equipment, greatly reducing manufacturing costs. Furthermore, compared with traditional forging processes, less raw materials are required, resulting in lower raw material costs. The casting and forging process provided by the present invention requires only a casting die, a pre-forging die, a final forging die, and a trimming die, and the forging die has a lifespan of up to 30,000 pieces. Traditional processes require these dies by adding an extrusion die, a roll forging die, and a bending die, resulting in a lifespan of 12,000 pieces. Therefore, the die cost is lower than that of traditional processes, and the die life is longer. This casting and forging process meets the conditions for mass production, with stable production quality and controllable scrap rate reaching the target of ≤1%; the scrap rate of traditional processes is ≤5%, which greatly reduces the scrap rate.

[0016] Other features and advantages of the present invention will be described in detail in the following detailed description. DETAILED DESCRIPTION

[0017] The following is a detailed description of the specific embodiments of the present invention. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0018] Example 1

[0019] The aluminum ingot is melted, heated to 800℃, kept warm for 30 minutes, then the temperature is reduced to 500℃, kept warm for 20 minutes, and then cast into a mold (wherein the heating rate is 4℃ / min and the cooling rate is 1℃ / min); the smelted aluminum ingot is cast and pre-formed to form a blank; the blank is homogenized, and the homogenization treatment is three-step heating treatment; including: the first stage homogenization treatment temperature is 350℃, and the holding time is 2h; the second stage homogenization treatment temperature is 480℃, and the holding time is 3h; the third stage homogenization treatment temperature is 500℃, and the holding time is 10h; cutting is carried out after inspection; pre-forging and final forging are carried out after heating; edge trimming is carried out after water cooling; heat treatment is carried out (temperature is 400℃, time is 40min); flaw detection and shot blasting are carried out after cleaning; finally, inspection and storage are carried out. The aluminum ingot includes the following components: 0.035% Cu, 1.14% Si, 0.201% Fe, 0.65% Mn, 0.13% Mg, 0.015% Ti, 0.02% Zn, 0.13% Cr, and the balance Al.

[0020] Example 2

[0021] The aluminum ingot is melted, heated to 900℃, kept warm for 40 minutes, then the temperature is reduced to 600℃, kept warm for 30 minutes, and then cast into a mold (wherein the heating rate is 6℃ / min and the cooling rate is 3℃ / min); the smelted aluminum ingot is cast and pre-formed to form a blank; the blank is homogenized, and the homogenization treatment is three-step heating treatment; including: the first stage homogenization treatment temperature is 460℃, and the holding time is 4h; the second stage homogenization treatment temperature is 510℃, and the holding time is 6h; the third stage homogenization treatment temperature is 650℃, and the holding time is 12h; cutting is carried out after inspection; pre-forging and final forging are carried out after heating; edge trimming is carried out after water cooling; heat treatment is carried out (temperature is 550℃, time is 50min); flaw detection and shot blasting are carried out after cleaning; finally, inspection and storage are carried out. The aluminum ingot includes the following components: 0.035% Cu, 1.14% Si, 0.201% Fe, 0.65% Mn, 0.13% Mg, 0.015% Ti, 0.02% Zn, 0.13% Cr, and the balance Al.

[0022] Example 3

[0023] The aluminum ingot is melted, heated to 850℃, kept warm for 35 minutes, then the temperature is reduced to 550℃, kept warm for 25 minutes, and then cast into a mold (wherein the heating rate is 5℃ / min and the cooling rate is 2℃ / min); the smelted aluminum ingot is cast and pre-formed to form a blank; the blank is homogenized, and the homogenization treatment is three-step heating treatment; including: the first stage homogenization treatment temperature is 400℃, and the holding time is 3h; the second stage homogenization treatment temperature is 500℃, and the holding time is 4h; the third stage homogenization treatment temperature is 550℃, and the holding time is 11h; cutting is carried out after inspection; pre-forging and final forging are carried out after heating; edge trimming is carried out after water cooling; heat treatment is carried out (temperature is 450℃, time is 45min); flaw detection and shot blasting are carried out after cleaning; finally, inspection and storage are carried out. The aluminum ingot includes the following components: 0.035% Cu, 1.14% Si, 0.201% Fe, 0.65% Mn, 0.13% Mg, 0.015% Ti, 0.02% Zn, 0.13% Cr, and the balance Al.

[0024] Comparative Example

[0025] The aluminum alloy forged control arm is manufactured using the traditional process: aluminum ingot melting - round ingot casting - homogenization - inspection - heating - bar extrusion - heat treatment - inspection - transportation - sawing - heating - roll forging - bending - forging (pre-forging) - heating - forging (final forging) - trimming - air cooling - heat treatment - cleaning - flaw detection - shot blasting - inspection - and storage. The control arm's specifications are: 2.4 kg, hardness HBW 90-130, tensile strength Rm ≥ 310 MPa, Rp0.2 yield strength ≥ 260 MPa, and elongation A ≥ 6%.

[0026] It can be seen from the above test data that compared with the traditional process, the process provided by the present invention requires less raw materials when manufacturing aluminum alloy forging control arms with standard parameters, and has higher yield strength and tensile strength. Under the premise that the product performance can meet the requirements of the drawings, the process is shorter than the traditional forging process, less equipment is required, and the manufacturing cost is low; the molds required for the new casting and forging process are only casting molds, pre-forging molds, final forging molds, and trimming molds, and the forging mold life can reach 30,000 pieces. The molds required by the traditional process are added with extrusion molds, roller forging molds, and bending molds on the premise of these molds. The forging mold life is 12,000 pieces, which is lower than the mold cost of the traditional process and has a longer mold life; the new casting and forging process meets the conditions for mass production, with stable production quality, controllable scrap rate and reaching the target of ≤1%; the scrap rate of the traditional process is ≤5%, which greatly reduces the scrap rate.

[0027] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the scope of protection of the present invention.

[0028] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0029] In addition, the various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A casting and forging process for aluminum alloy forgings for new energy vehicles, characterized in that: The casting and forging process includes: (1) smelting aluminum ingots; (2) casting and preforming the smelted aluminum ingots to form a blank; (3) homogenizing the blank; (4) cutting after inspection; (5) pre-forging and final forging after heating; (6) trimming after water cooling; (7) heat treatment; (8) flaw detection and shot blasting after cleaning; and (9) finally inspection and storage.

2. The casting and forging process of aluminum alloy forgings for new energy vehicles according to claim 1, wherein: The smelting step in step (1) includes: heating the aluminum ingot to 800-900°C, keeping it warm for 30-40 minutes, lowering the temperature to 500-600°C, keeping it warm for 20-30 minutes, and then casting it into a mold for pre-forming.

3. The casting and forging process of aluminum alloy forgings for new energy vehicles according to claim 2, wherein: The heating rate is 4-6℃ / min, and the cooling rate is 1-3℃ / min.

4. The casting and forging process of aluminum alloy forgings for new energy vehicles according to claim 1, wherein: In step (3), the homogenization treatment is performed by stepwise heating for three times; Including: the temperature of the first stage homogenization treatment is 350-460℃, and the insulation time is 2-4h; The temperature of the second stage homogenization treatment is 480-510℃, and the holding time is 3-6h; The temperature of the third stage homogenization treatment is 500-650°C, and the insulation time is 10-12h.

5. The casting and forging process of aluminum alloy forgings for new energy vehicles according to claim 1, wherein: In step (7), the heat treatment conditions include: temperature of 400-550°C and time of 40-50 min.

6. The casting and forging process of aluminum alloy forgings for new energy vehicles according to any one of claims 1 to 5, wherein: The aluminum ingot includes the following components: 0.035-0.1% Cu, 1.14-1.35% Si, 0.201-0.32% Fe, 0.65-0.82% Mn, 0.13-0.82% Mg, 0.015-0.045% Ti, 0.02-0.065% Zn, 0.13-0.85% Cr, and the balance Al.

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