Improved magnesium alloy plate

Abstract

The invention relates to an improved magnesium alloy plate, which comprises the following elements in percentage by weight: 94.55-96.40% of magnesium; 2.70%-3.5% of aluminum; 0.7% to 1.2% of zinc; 0.2% to 0.4% of manganese; 0 to 0.1 percent of silicon; 0 to 0.05 percent of copper; 0 to 0.04% of calcium; 0 to 0.005 percent of iron; 0 to 0.005% of nickel; the AZ31B magnesium alloy plate has the beneficial effects that under the condition that the AZ31B magnesium alloy standard meeting and tightening ASTM B90 is met, the components of the AZ31B magnesium alloy plate are adjusted, namely, the weight proportion of the aluminum element is increased, so that the ductility of the stamping alloy is improved, meanwhile, the weight proportion of the manganese element is controlled, and the improved AZ31B magnesium alloy plate is universal under the ASTM B90 standard; and meanwhile, the shell performance and appearance requirements of an existing electronic product are met, the ductility of the alloy at the normal temperature to 300 DEG C under stamping machining is improved, and the problems of wrinkles, dark cracks and the like cannot occur during stamping and edge folding.

Description

[Technical field]

[0001] The invention relates to the technical field of magnesium alloy plates, in particular to an improved magnesium alloy plate. [Background technology]

[0002] Magnesium alloy materials have long been used in the molding of laptop shells. They are the lightest metal structural materials with strength and modulus exceeding that of engineering plastics. The magnesium content is very rich, and their composite materials can be die-cast or stamped. AZ31B magnesium alloy material is a type of magnesium alloy stamping material with good mechanical properties. It is mainly used in automotive parts, machine shells and communication equipment. In recent years, AZ31B magnesium alloy materials have gradually been promoted and applied in laptop shells. Its thickness below 0.6 mm has more mass production advantages than cast magnesium alloys. At the same time, the plates formed by AZ31B magnesium alloy materials can also save the cost of surface treatment.

[0003] Currently, under the ASTM B90 / B90M standard, the ductility and formability of stamped sheets of AZ31B magnesium alloy cannot meet the requirements of existing electronic product shells, and there may be wrinkling problems after elongation.

[0004] In view of this, it is necessary to provide an improved magnesium alloy sheet to solve the above problems. [Summary of the invention]

[0005] The technical problem to be solved by the present invention is that the stamping sheet of AZ31B magnesium alloy material cannot meet the requirements of the shell of existing electronic products in terms of ductility and formability in accordance with the ASTM B90 / B90M standard, and there may be wrinkles after elongation. Therefore, the present invention provides an improved magnesium alloy sheet to solve the above problems.

[0006] The solution of the present invention to solve the technical problem is:

[0007] An improved magnesium alloy sheet, characterized in that it comprises the following elements in weight proportion:

[0008] Magnesium, 94.55-96.40%;

[0009] Aluminum, 2.70-3.5%;

[0010] Zinc, 0.7-1.2%;

[0011] Manganese, 0.2-0.4%;

[0012] Silicon, 0-0.1%;

[0013] Copper, 0-0.05%;

[0014] Calcium, 0-0.04%;

[0015] Iron, 0-0.005%;

[0016] Nickel, 0-0.005%;

[0017] Others: 0-0.3%.

[0018] Preferably, the aluminum generates magnesium-aluminum intergranular compounds in the AZ31B magnesium alloy. The structure of the γ-phase magnesium-aluminum intergranular compounds is different from that of the α-magnesium hexagonal close-packed crystals (HCP). At room temperature, the α-magnesium can be prevented from sliding, thereby achieving the purpose of alloy strengthening. However, the γ-magnesium-aluminum intergranular compounds can slide at high temperatures. Under high temperature conditions, the machinability of the material is enhanced, that is, the weight proportion of the aluminum element is increased in the present invention to improve the ductility of the stamping alloy.

[0019] Preferably, the manganese forms aluminum-manganese intergranular compounds in the AZ31B magnesium alloy, and its properties will affect the high-temperature stamping performance and ductility of the magnesium alloy, that is, the weight proportion of the manganese element is controlled in the present invention.

[0020] Preferably, the weight ratio of the aluminum to manganese elements is as follows: aluminum (%) - manganese (%) x 2.95>1.5 (%).

[0021] Preferably, the other elements are metal impurities.

[0022] A product, characterized in that the product is prepared by increasing the weight proportion of aluminum elements and controlling the weight proportion of manganese elements.

[0023] The beneficial effect of the present invention is that the present invention adjusts the composition of the AZ31B magnesium alloy sheet under the AZ31B magnesium alloy standard that complies with ASTM B90, that is, increases the weight proportion of the aluminum element to improve the ductility of the stamping alloy, and at the same time controls the weight proportion of the manganese element, so that the composition of the improved AZ31B magnesium alloy sheet is compatible with the background AZ31B magnesium alloy under the ASTM B90 standard, and at the same time meets the shell performance and appearance requirements of existing electronic products, improves the low-temperature ductility of the alloy under stamping processing, and does not cause wrinkles, dark cracks, and other problems during stamping and folding. [Specific implementation method]

[0024] To further illustrate the technical means and effects adopted by the present invention, the following is a detailed description in conjunction with the embodiments of the present invention.

[0025] An improved magnesium alloy sheet, characterized in that it comprises the following elements in weight proportion:

[0026] Magnesium, 94.55-96.40%;

[0027] Aluminum, 2.70-3.5%;

[0028] Zinc, 0.7-1.2%;

[0029] Manganese, 0.2-0.4%;

[0030] Silicon, 0-0.1%;

[0031] Copper, 0-0.05%;

[0032] Calcium, 0-0.04%;

[0033] Iron, 0-0.005%;

[0034] Nickel, 0-0.005%;

[0035] Others: 0-0.3%.

[0036] Among them, the aluminum generates magnesium-aluminum intergranular compounds in the AZ31B magnesium alloy. The structure of the γ-phase magnesium-aluminum intergranular compound is different from that of the α-magnesium hexagonal close-packed crystal (HCP). At room temperature, it can prevent the α-magnesium from sliding, thereby achieving the purpose of alloy strengthening. However, the γ-magnesium-aluminum intergranular compound can slide at high temperatures, and the material machinability is enhanced. That is, in the present invention, the weight proportion of the aluminum element is increased to improve the ductility of the stamping alloy.

[0037] Among them, the manganese forms aluminum-manganese intergranular compounds in the AZ31B magnesium alloy. The intergranular compounds can make the magnesium alloy nucleate and crystallize at high temperatures, which helps to reduce the grain structure of the cast magnesium alloy. The grain structure size affects the alloy processing characteristics, and the warm stamping forming technology is a way to increase the temperature to process the product appearance. The material needs to have appropriate high-temperature processing characteristics, that is, the weight proportion of the manganese element is controlled in the present invention.

[0038] The weight ratio of aluminum to manganese is as follows: aluminum (%) - manganese (%) x 2.95>1.5 (%).

[0039] Wherein, the other elements are metal impurities.

[0040] Example 1

[0041] An improved magnesium alloy plate comprises the following elements in weight proportion: 95.6674-95.6681% magnesium, 3.08% aluminum, 0.842% zinc, 0.0011% iron, less than 0.00030% copper, 0.397% manganese, less than 0.00040% nickel, and 0.0118% silicon.

[0042] When preparing the improved magnesium alloy plate, the elements are weighed in corresponding weight portions according to the above proportions, and the components are poured and then pressed into plates.

[0043] Example 2

[0044] An improved magnesium alloy plate comprises the following elements in weight proportion: 95.6625-95.6632% magnesium, 3.36% aluminum, 0.716% zinc, 0.0010% iron, less than 0.00030% copper, 0.251% manganese, less than 0.00040% nickel, and 0.0088% silicon.

[0045] When preparing the improved magnesium alloy plate, the elements are weighed in corresponding weight portions according to the above proportions, and the components are poured and then pressed into plates.

[0046] Example 3

[0047] An improved magnesium alloy plate comprises the following elements in weight proportion: 95.5123-95.5130% magnesium, 3.37% aluminum, 0.830% zinc, 0.0014% iron, less than 0.00030% copper, 0.259% manganese, less than 0.00040% nickel, and 0.0266% silicon.

[0048] When preparing the improved magnesium alloy plate, the elements are weighed in corresponding weight portions according to the above proportions, and the components are poured and then pressed into plates.

[0049] Example 4

[0050] An improved magnesium alloy plate comprises the following elements in weight proportion: 96.2146-96.2153% magnesium, 2.72% aluminum, 0.7% zinc, 0.0012% iron, less than 0.00030% copper, 0.374% manganese, less than 0.00040% nickel, and 0.0075% silicon.

[0051] When preparing the improved magnesium alloy plate, the elements are weighed in corresponding weight portions according to the above proportions, and the components are poured and then pressed into plates.

[0052] Comparative Example 1

[0053] The comparative example magnesium alloy plate includes the following elements in weight proportion: 95.4086-95.4093% magnesium, 2.90% aluminum, 1.200% zinc, 0.0002% iron, less than 0.00030% copper, 0.490% manganese, less than 0.00040% nickel, and 0.0005% silicon.

[0054] When preparing the improved magnesium alloy plate, the elements are weighed in corresponding weight portions according to the above proportions, and the components are poured and then pressed into plates.

[0055] Comparative Example 2

[0056] The comparative magnesium alloy plate includes the following elements in weight proportion: 96.0194-96.0201% magnesium, 2.58% aluminum, 0.863% zinc, 0.0015% iron, less than 0.00030% copper, 0.520% manganese, less than 0.00040% nickel, and 0.0154% silicon.

[0057] When preparing the magnesium alloy plate, the elements in corresponding weight portions are weighed according to the above proportions, and each component is poured and then pressed into a plate.

[0058] After the above embodiments are implemented, they are reproduced according to the same proportion, and the pressing plates after casting are made of Embodiment 1, Embodiment 2, Embodiment 3, Embodiment 4, wherein the control examples 1 and 2 do not meet the aluminum-manganese ratio proposed in this invention, and can be used as controls. The mechanical properties of the obtained materials are tested according to the standard, and the test results are shown in Table 1:

[0059] Table 1 Test results

[0060] Test items Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Tensile strength(MPa) 256 267 275 268 250 268 Total elongation at break (%) 23 25 24 20 23 25 Stamping test normal normal normal normal Cracking Cracking

[0061] The samples of Example 1, Example 2, Example 3, and Example 4 were tested according to the ASTM B90M standard (without an extensometer). The test results show that the present invention achieves the preparation of an improved magnesium alloy sheet by increasing the weight proportion of the aluminum element and controlling the weight proportion of the manganese element while meeting the ASTM B90M standard.

[0062] The beneficial effect of the present invention is that the present invention adjusts the composition of the AZ31B magnesium alloy sheet under the AZ31B magnesium alloy standard that complies with ASTM B90, that is, increases the weight proportion of the aluminum element to improve the ductility of the stamping alloy, and at the same time controls the weight proportion of the manganese element, so that the composition of the improved AZ31B magnesium alloy sheet is compatible with the AZ31B magnesium alloy in the background under the ASTM B90 standard, and at the same time meets the shell performance and appearance requirements of existing electronic products and improves the low-temperature ductility of the alloy under stamping processing, and when stamping and folding, due to the improved ductility of the material at the processing temperature, Example 1, Example 2, Example 3, and Example 4 will not have problems such as wrinkles and dark cracks, while Control Example 1 and Control Example 2 will have problems such as cracks and dark cracks.

[0063] It should be pointed out that the present invention is not limited to the above-mentioned implementation modes, and any simple modifications, equivalent changes and modifications made to the above-mentioned embodiments by any technician familiar with the profession based on the technical solution of the present invention fall within the protection scope of the present invention.

Claims

1. An improved magnesium alloy sheet, characterized in that: Includes the following elements in proportion by weight: Magnesium, 94.55-96.40%; Aluminum, 2.70-3.5%; Zinc, 0.7-1.2%; Manganese, 0.2-0.4%; Silicon, 0-0.1%; Copper, 0-0.05%; Calcium, 0-0.04%; Iron, 0-0.005%; Nickel, 0-0.005%; Others: 0-0.3%.

2. The improved magnesium alloy sheet material according to claim 1, characterized in that: The mass ratio of the aluminum to manganese elements is as follows: aluminum (%) - manganese (%) x 2.95>1.5 (%).

3. The improved magnesium alloy sheet material according to claim 1, characterized in that: The other elements are metal impurities.