Al-mn-fe-si alloy with high strength and processability and preparation method thereof
By adding Er and Zr elements and controlling the Fe and Si content, combined with hot rolling, cold rolling and annealing treatments, the Al-Mn-Fe-Si alloy prepared solves the problem of simultaneously improving strength and plasticity, and achieves high strength and toughness and good formability, which is suitable for battery pack shell materials for new energy vehicles.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-03
- Publication Date
- 2026-08-04
AI Technical Summary
While ensuring formability, existing 3003 series aluminum alloys have difficulty simultaneously improving strength and plasticity. Furthermore, high iron content can easily generate coarse phases, reducing the material's toughness and plasticity.
Al-Mn-Fe-Si alloys were prepared by adding Er and Zr elements, controlling the content and ratio of Fe and Si, forming fine dispersed phases, and suppressing the formation of coarse phases, combined with hot rolling, cold rolling and annealing treatments.
It improves the strength and plasticity of the alloy, enhances its processing and forming properties, and does not significantly increase cost or density, thus broadening its application prospects.
Smart Images
Figure CN122503702A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of alloy technology, specifically to an Al-Mn-Fe-Si alloy with both high strength and toughness and good processing and forming properties, and its preparation method. Background Technology
[0002] In the field of new energy vehicles, battery pack casing materials need to simultaneously consider lightweight, safety performance, corrosion resistance, and economic cost. Currently, the widely used 3003 series aluminum alloys are aluminum-manganese alloys that cannot be heat-treatable and are often used in various structural components of lithium batteries.
[0003] Existing processes mainly rely on traditional cold rolling work hardening (H14, H18, etc.) to improve the strength of the alloy; at the same time, manganese is used to form dispersed intermetallic compounds such as Al6(Mn,Fe) and Al6Mn in the aluminum matrix to achieve dispersion strengthening, and combined with solid solution strengthening of other elements, the overall performance of the alloy is further improved.
[0004] While traditional cold-rolled 3003 series aluminum alloys possess high strength, their plasticity is generally low. For example, the elongation in the H18 state is only about 4%, making them prone to cracking during stamping. Furthermore, when the iron content in the alloy is high, coarse Al6(Mn,Fe) phases are easily formed. These incoherent coarse phases can cleave the aluminum matrix, becoming crack initiation sites and significantly reducing the material's plasticity and toughness.
[0005] In summary, how to simultaneously improve strength and plasticity while ensuring the excellent formability of 3003 series aluminum alloys has become a major challenge that urgently needs to be overcome in the alloy composition design. Summary of the Invention
[0006] To address at least one of the aforementioned technical deficiencies, the present invention provides the following technical solution: The first aspect of this invention discloses an Al-Mn-Fe-Si alloy that combines high strength and toughness with good processing and forming properties, comprising the following components by mass: Mn: 1.0-1.5%, Cu: 0.05-0.20%, Fe: ≤0.7%, Si: ≤0.6%, Zr: 0.05-0.20%, Er: 0.10-0.30%, Al: balance.
[0007] Furthermore, the atomic percentage ratio of Zr / Er is 1:1, and the atomic percentage ratio of Fe / Si is 2:1.
[0008] Furthermore, it also includes Mg: 0.4-0.6%.
[0009] The second aspect of this invention discloses a method for preparing an Al-Mn-Fe-Si alloy that combines high strength and toughness with good processing and formability, comprising the following steps: The ingots are prepared according to the component ratios described above; The prepared ingots were subjected to homogenization annealing at 550-600℃ for 4 hours. The annealed ingots are then subjected to hot rolling and cold rolling processes in sequence. The sheet material formed after cold rolling is then annealed.
[0010] Furthermore, after homogenization annealing and air cooling, the thickness of the rolled plate is 2-2.5 mm when hot rolling and cold rolling are performed sequentially.
[0011] Furthermore, the cold-rolled sheet is annealed at 300-430℃ for 0.5-2 hours, followed by furnace cooling or air cooling.
[0012] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention adds Er and Zr elements, and utilizes the synergistic effect of Er and Zr elements to induce the formation of fine and dispersed Al3(Zr,Er) phase in the alloy. It acts as a heterogeneous nucleation support to refine the grains. At the same time, it can suppress the recrystallization process in subsequent processing. In addition, Er element can suppress Zr segregation, making the precipitated phase less coarsened. The combination of phases improves the yield strength of the alloy.
[0013] 2. This invention, by adding Er and Zr elements, simultaneously controls the content and ratio of impurity elements Fe and Si to suppress the formation of coarse Al6(Mn,Fe) phase and promote the formation of spherical or blocky semi-coherent α-Al(Fe,Mn)Si phase, thereby improving the precipitation strengthening effect. The prepared alloy balances high strength and toughness with good processability, effectively improving the current problems of insufficient strength and plasticity in 3003 series aluminum alloys.
[0014] 3. Compared with traditional 3003 series aluminum alloys, the alloy prepared by this invention does not significantly increase in cost and density, but greatly increases the use value of the alloy, thereby broadening the application prospects of 3003 series aluminum alloys. Attached Figure Description
[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0016] Figure 1 For Al 98.72 Mn0.62 Cu 0.04 Fe 0.32 Si 0.21 Zr 0.04 Er 0.04 OM microstructure of the alloy.
[0017] Figure 2 For Al 98.72 Mn 0.62 Cu 0.04 Fe 0.32 Si 0.21 Zr 0.04 Er 0.04 SEM backscattered electronic phase of the alloy.
[0018] Figure 3 For Al 98.72 Mn 0.62 Cu 0.04 Fe 0.32 Si 0.21 Zr 0.04 Er 0.04 Tensile stress-strain curve of the alloy.
[0019] Figure 4 For Al 98.72 Mn 0.62 Cu 0.04 Fe 0.32 Si 0.21 Zr 0.04 Er 0.04 EPMA image of the alloy. Detailed Implementation
[0020] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.
[0021] The preparation method of the alloy includes the following steps: According to the component ratio shown in Table 1, the ingredients are prepared and placed in a water-cooled copper crucible in an electric arc melting furnace. The melting is carried out under argon protection using a non-consumable arc melting method with a current of 250A. After five repeated melting processes, a uniform alloy ingot is obtained. The alloy ingot is then melted and cast into a cast ingot.
[0022] The prepared ingots were subjected to homogenization annealing at 600℃ for 4 hours and then air-cooled to room temperature.
[0023] After annealing, the ingots are subjected to hot rolling and cold rolling processes in sequence, with a reduction of 0.5 mm per pass, until the plate thickness is 2.3 mm.
[0024] The cold-rolled sheet was annealed at 350°C for 1 hour and then cooled in the furnace.
[0025] The tensile strength, yield strength, and elongation after fracture of the prepared alloy were tested, as shown in Tables 1 and 2.
[0026] Table 1
[0027] Where 'real 1' represents Example 1, 'compare 1' represents Comparative Example 1, and so on.
[0028] Table 2
[0029] Where 'real 1' represents Example 1, 'compare 1' represents Comparative Example 1, and so on.
[0030] Simultaneously, the microstructure and tensile strain of the alloy prepared in Experiment 1 were characterized and analyzed. Figure 1 It can be seen that the H14 tissue still retains some rolling orientation when observed under an optical microscope.
[0031] from Figure 2 It can be seen that under higher resolution backscattered images, different precipitates have different diffraction contrasts. After statistical analysis of particle sizes, it was found that the precipitates become smaller after adding Zr and Er elements.
[0032] from Figure 3 It can be seen that the addition of Zr and Er elements improves the tensile properties of the alloy, with the tensile strength reaching over 190 MPa and the elongation after fracture also exceeding 6%.
[0033] from Figure 4 As can be seen from the surface elemental distribution analysis under EPMA, Zr elements are evenly distributed, Er elements are slightly agglomerated, but most of them also form Al3 (Zr, Er) with the Al matrix. Both kinds of tiny particles act as nucleation sites to refine the grains.
[0034] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of the present invention should also be considered within the scope of protection of the present invention.
Claims
1. An Al-Mn-Fe-Si alloy possessing both high strength and toughness, as well as good machinability, characterized in that, By mass, it comprises the following components: Mn: 1.0-1.5%, Cu: 0.05-0.20%, Fe: ≤0.7%, Si: ≤0.6%, Zr: 0.05-0.20%, Er: 0.10-0.30%, Al: balance.
2. The Al-Mn-Fe-Si alloy with high strength and toughness and good machinability as described in claim 1, characterized in that: The atomic percentage ratio of Zr / Er is 1:1, and the atomic percentage ratio of Fe / Si is 2:
1.
3. The Al-Mn-Fe-Si alloy with high strength and toughness and good machinability as described in claim 1, characterized in that: It also includes Mg: 0.4-0.6%.
4. A method for preparing an Al-Mn-Fe-Si alloy possessing both high strength and toughness, as well as good machinability, characterized in that: Includes the following steps: The ingot is prepared according to the component ratio shown in claim 1 or 2; The prepared ingots were subjected to homogenization annealing at 550-600℃ for 4 hours. The annealed ingots are then subjected to hot rolling and cold rolling processes in sequence. The sheet material formed after cold rolling is then annealed.
5. The method for preparing an Al-Mn-Fe-Si alloy with both high strength and toughness and good machinability as described in claim 4, characterized in that: After homogenization annealing, the material is air-cooled and then hot-rolled and cold-rolled until the thickness of the sheet is 2-2.5 mm.
6. The method for preparing an Al-Mn-Fe-Si alloy with high strength, toughness, and machinability as described in claim 4, characterized in that: The cold-rolled sheet is annealed at 300-430℃ for 0.5-2 hours, and then cooled in the furnace or in the air.