Alloy for preparing anti-snakelike shock absorber seat of train built-in bogie and preparation method of alloy

Abstract

The invention discloses an alloy for preparing an anti-snakelike shock absorber seat of a train built-in bogie and a preparation method of the alloy, and belongs to the technical field of metal materials. The alloy comprises the following components in parts by weight: 5%-8% of Zn, 1.5%-3% of Mg, 2.0%-5% of Cu, 0.1%-0.5% of Zr, 0.04%-0.5% of Ti, 0.05%-0.5% of Y, 2.5%-4.5% of Si, 0.05%-0.5% of Co, 0.1%-0.5% of Nb and the balance of Al and inevitable impurities. Through cooperation of Zn, Mg, Cu, Si, Co, Nb and other components, the prepared alloy product has excellent tensile strength, yield strength and percentage elongation after fracture, and the mechanical property of the alloy is remarkably improved.

Description

Technical Field

[0001] The invention belongs to the technical field of metal materials, and in particular relates to an alloy for preparing an anti-snake shock absorber seat of a built-in bogie of a train and a preparation method thereof. Background Art

[0002] With the gradual increase in the speed of high-speed trains and the important demand for energy conservation and environmental protection, the further lightweighting of high-speed trains has become a basic element in the design and manufacture of high-speed trains, and it is also an inevitable trend. The shock absorbers of the currently operating high-speed trains are mainly made of ductile iron, resulting in a high overall quality of the shock absorbers. As a lightweight structural material, alloys have the advantages of low density, high strength, good electrical and thermal conductivity, good corrosion resistance, easy forming and processing, etc., and have been widely used in the manufacturing field of high-speed trains. However, the shock absorber bases currently produced are difficult to meet the high requirements of high-speed trains in terms of performance. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the present invention provides an alloy for preparing an anti-snake shock absorber seat for a built-in train bogie and a preparation method thereof, which can effectively improve the strength, hardness and other mechanical properties of the prepared material.

[0004] To achieve the above purpose, the technical solution adopted by the present invention to solve the technical problem is:

[0005] The object of the present invention is to provide an alloy for preparing an anti-snake shock absorber seat of a train built-in bogie, comprising the following components in parts by weight:

[0006] Zn 5-8%, Mg 1.5-3%, Cu 2.0-5%, Zr 0.1-0.5%, Ti 0.04-0.5%, Y 0.05~0.5%, Si 2.5~4.5%, Co 0.05~0.5%, Nb 0.1~0.5%, and the rest are Al and unavoidable impurities.

[0007] Further, the following components are included in parts by weight:

[0008] Zn 5.8-7.6%, Mg 1.5-1.9%, Cu 2.0-2.5%, Zr 0.1-0.2%, Ti 0.04-0.12%, Y0.05~0.35%, Si 3~4.5%, Co 0.1~0.5%, Nb 0.1~0.5%, and the rest are Al and unavoidable impurities.

[0009] Further, the following components are included in parts by weight:

[0010] Zn 6%, Mg 1.5%, Cu 2.5%, Zr 0.1%, Ti 0.1%, Y 0.1%, Si 4.5%, Co 0.5%, Nb 0.1%, and the rest are Al and inevitable impurities.

[0011] Furthermore, the total amount of the inevitable impurities is controlled to be 0.05-0.15% by weight, and the content of each impurity in the inevitable impurities is ≤0.05% by weight.

[0012] Further, the inevitable impurities include at least one of Ca, V, P, Fe and Mn.

[0013] Another object of the present invention is to provide a method for preparing the above alloy, comprising the following steps:

[0014] (1) pure Al is heated and melted, then the melt temperature is raised to 680°C-700°C, and Al-Cu master alloy is added;

[0015] (2) Continue to raise the melt temperature to 720-740°C, add Al-Zr, Al-Ti, Al-Y, and Al-Si master alloys, and perform the first refining;

[0016] (3) Continue to lower the melt temperature to 690-710°C, then add pure Zn and pure Mg, and perform a second refining;

[0017] (4) The melt is heated to 720-730°C, Al-Co and Al-Nb master alloys are added, stirred for 2-5 minutes, and then allowed to stand for 5-10 minutes; when the temperature drops to 710-720°C, stirred until a semi-solid metal liquid is formed, and then cast to obtain the alloy.

[0018] Furthermore, in step (2) and step (3), refining is performed using a refining agent and / or a refining gas.

[0019] Furthermore, the refining agent is chloride salt, and the refining gas is inert gas.

[0020] Furthermore, the chloride salt is potassium chloride or copper chloride; and the inert gas is nitrogen or argon.

[0021] Another object of the present invention is to provide a train built-in bogie anti-snake shock absorber seat, which is made of the above alloy, and the specific process is as follows:

[0022] (1) casting the alloy to form a casting billet and removing the outer skin, heating to 380-450° C. and keeping the temperature for 8-14 hours, then continuing to heat to 450-490° C. and keeping the temperature for 20-26 hours, and cooling with water at room temperature;

[0023] (2) heating the treated alloy billet to 380-450°C for 2-6 hours, and then hot extruding, with the preheating temperature of the extrusion barrel being 380-450°C and the extrusion ratio being ≥10;

[0024] (3) heating the alloy extrusion billet obtained in step (2) to 380-450° C. and keeping the temperature for 2-6 hours;

[0025] (4) The alloy blank obtained in step (3) is subjected to superplastic die forging, wherein the die preheating temperature is 380-450°C, the die forging temperature is 380-450°C, and the die forging rate is 10×10 -5 ~10×10 -2 mm / s, and the pre-cut alloy shock absorber forging blank is obtained;

[0026] (5) The alloy shock absorber seat forging blank obtained in step (4) is subjected to superplastic die forging final forging, the die preheating temperature is 380-450°C, the die forging temperature is 380-450°C, and the die forging rate is 10×10 -5 ~10×10 -2 mm / s, and the alloy shock absorber seat forging blank with final forging treatment is obtained;

[0027] (6) The alloy shock absorber seat forging blank obtained in step (5) is subjected to rough processing, heat treatment and fine processing in sequence to obtain the integral shock absorber seat for the built-in bogie of the train.

[0028] Beneficial effects of the present invention:

[0029] 1. The Si and Mg in the present invention can form a Mg2Si phase, which has a strengthening effect on the matrix. In addition, Si also exists in the form of eutectic silicon, which also ensures that the alloy has excellent fluidity during preparation, is conducive to the subsequent molding of the shock absorber seat component, and can also ensure a good match of the strength and toughness of the alloy.

[0030] 2. The present invention adds Co element to the formula and does not use Mn element. The present application replaces Mn element with Co, which effectively avoids the weakening of alloy toughness by Mn element. In addition, Co element can reduce the secondary dendrite arm spacing, enhance the shrinkage compensation ability, and reduce the alloy's thermal cracking tendency. In addition, Co has a certain refinement effect on α-Al. During the aging process, Co will precipitate a large number of dispersed Co-rich nano-reinforced particles, which greatly improves the strength and toughness of the alloy. At the same time, the composite modification of Co and Zr significantly refines the size of eutectic silicon, while solving the problem of the aging of Zr alone, and achieving long-term effective modification.

[0031] 3. The present invention generates a corresponding precipitate phase by adding Nb element, which can precipitate in coordination with Al3Y nanophase, hinder dislocation slip and maintain coherence with the parent phase, thereby improving the strength, hardness and recoverable strain of the alloy and improving the comprehensive mechanical properties of the alloy.

[0032] 4. Stirring to form semi-solid molten metal before alloy pouring. Stirring can break up the dendrite network skeleton in the molten metal to form a dispersed granular organizational form, which is suspended in the remaining liquid phase, thereby making a semi-solid molten metal with a small solidification shrinkage rate. It can avoid defects such as shrinkage holes, looseness, and mold sticking in the subsequent preparation process of the shock-absorbing base, and improve the mechanical properties of the shock-absorbing base. DETAILED DESCRIPTION

[0033] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0034] Example 1

[0035] An alloy for preparing an anti-snake shock absorber seat of a train built-in bogie comprises the following components in parts by weight:

[0036] Zn 6%, Mg 1.5%, Cu 2.5%, Zr 0.1%, Ti 0.1%, Y 0.1%, Si 4.5%, Co 0.5%, Nb 0.1%, and the rest are Al and inevitable impurities.

[0037] The preparation method of the alloy is as follows:

[0038] Another object of the present invention is to provide a method for preparing the above alloy, comprising the following steps:

[0039] (1) pure Al is heated and melted, then the melt temperature is raised to 680°C, and Al-Cu master alloy is added;

[0040] (2) The melt temperature is further raised to 740°C, Al-Zr, Al-Ti, Al-Y, and Al-Si master alloys are added, and potassium chloride is used for the first refining;

[0041] (3) The melt temperature is further lowered to 690°C, and then pure Zn and pure Mg are added, and nitrogen is used for a second refining;

[0042] (4) The melt is heated to 730°C, Al-Co and Al-Nb master alloys are added, stirred for 2-5 minutes, and then allowed to stand for 5-10 minutes; when the temperature drops to 710°C, stirred until a semi-solid metal liquid is formed, and then cast to obtain the alloy.

[0043] A train built-in bogie anti-snake shock absorber seat is made of the above alloy, and the specific process is as follows:

[0044] (1) Casting alloy ingot: The alloy ingot is prepared by the above method.

[0045] (2) Homogenization treatment: remove the outer skin of the alloy ingot obtained in step (1), heat to 380°C and keep it for 12 h, then continue to heat to 490°C and keep it for 20 h, and cool it with water at room temperature.

[0046] (3) Hot extrusion: The alloy billet obtained in step (2) is heated to 450°C and kept at this temperature for 4 hours, and then hot extruded. The preheating temperature of the extrusion barrel is 380°C, and the extrusion ratio is ≥10.

[0047] (4) Preheating: Heat the alloy extrusion billet obtained in step (3) to 380°C and keep it warm for 2-6 hours.

[0048] (5) Superplastic die forging: The alloy blank obtained in step (4) is placed in a pre-forging die for superplastic die forging to obtain an alloy shock absorber seat forging blank. The die preheating temperature is 450°C, the die forging temperature is 450°C, and the die forging rate is 10×10 - 5 mm / s.

[0049] (6) Superplastic die forging final forging: The alloy billet obtained in step (5) is placed in a final forging die for superplastic die forging to obtain an alloy shock absorber seat forging billet. The die preheating temperature is 450°C, the die forging temperature is 380°C, and the die forging rate is 10×10 - 5 mm / s.

[0050] (7) Rough machining: The alloy shock absorber seat forging blank obtained in step (6) is rough machined according to the shock absorber seat rough machining drawing.

[0051] (8) Heat treatment: The rough-machined alloy shock absorber seat obtained in step (7) is heated to 500° C. and kept at this temperature for 3 h, and then water-cooled at room temperature; then heated to 140° C. and kept at this temperature for 26 h, and then air-cooled.

[0052] (9) Finishing: The alloy shock absorber seat obtained in step (8) is finished according to the shock absorber seat finishing drawing.

[0053] Example 2

[0054] An alloy for preparing an anti-snake shock absorber seat of a train built-in bogie comprises the following components in parts by weight:

[0055] Zn 5%, Mg 1.5%, Cu 2.0%, Zr 0.1%, Ti 0.04%, Y 0.05%, Si 2.5%, Co 0.05%, Nb 0.1%, and the rest are Al and inevitable impurities.

[0056] The preparation method of the alloy is as follows:

[0057] Another object of the present invention is to provide a method for preparing the above alloy, comprising the following steps:

[0058] (1) Pure Al is heated and melted, then the melt temperature is raised to 700°C and Al-Cu master alloy is added;

[0059] (2) The melt temperature is further raised to 740°C, Al-Zr, Al-Ti, Al-Y, and Al-Si master alloys are added, and potassium chloride is used for the first refining;

[0060] (3) The melt temperature is further lowered to 710°C, and then pure Zn and pure Mg are added, and nitrogen is used for a second refining;

[0061] (4) The melt is heated to 730°C, Al-Co and Al-Nb master alloys are added, stirred for 2-5 minutes, and then allowed to stand for 5-10 minutes; when the temperature drops to 710°C, stirred until a semi-solid metal liquid is formed, and then cast to obtain the alloy.

[0062] A train built-in bogie anti-snake shock absorber seat is made of the above alloy, and the specific process is as follows:

[0063] (1) Casting alloy ingot: The alloy ingot is prepared by the above method.

[0064] (2) Homogenization treatment: remove the outer skin of the alloy ingot obtained in step (1), heat to 380°C and keep it for 12 h, then continue to heat to 490°C and keep it for 20 h, and cool it with water at room temperature.

[0065] (3) Hot extrusion: The alloy billet obtained in step (2) is heated to 450°C and kept at this temperature for 4 hours, and then hot extruded. The preheating temperature of the extrusion barrel is 380°C, and the extrusion ratio is ≥10.

[0066] (4) Preheating: Heat the alloy extrusion billet obtained in step (3) to 380°C and keep it warm for 2-6 hours.

[0067] (5) Superplastic die forging: The alloy blank obtained in step (4) is placed in a pre-forging die for superplastic die forging to obtain an alloy shock absorber seat forging blank. The die preheating temperature is 450°C, the die forging temperature is 450°C, and the die forging rate is 10×10 - 5 mm / s.

[0068] (6) Superplastic die forging final forging: The alloy billet obtained in step (5) is placed in a final forging die for superplastic die forging to obtain an alloy shock absorber seat forging billet. The die preheating temperature is 450°C, the die forging temperature is 380°C, and the die forging rate is 10×10 - 5 mm / s.

[0069] (7) Rough machining: The alloy shock absorber seat forging blank obtained in step (6) is rough machined according to the shock absorber seat rough machining drawing.

[0070] (8) Heat treatment: The rough-machined alloy shock absorber seat obtained in step (7) is heated to 500° C. and kept at this temperature for 3 h, and then water-cooled at room temperature; then heated to 140° C. and kept at this temperature for 26 h, and then air-cooled.

[0071] (9) Finishing: The alloy shock absorber seat obtained in step (8) is finished according to the shock absorber seat finishing drawing.

[0072] Example 3

[0073] An alloy for preparing an anti-snake shock absorber seat of a train built-in bogie comprises the following components in parts by weight:

[0074] Zn 8%, Mg 3%, Cu 5%, Zr 0.5%, Ti 0.5%, Y 0.5%, Si 4.5%, Co 0.5%, Nb 0.5%, and the rest are Al and inevitable impurities.

[0075] The preparation method of the alloy is as follows:

[0076] Another object of the present invention is to provide a method for preparing the above alloy, comprising the following steps:

[0077] (1) Heat pure Al to melt, then raise the melt temperature to 680°C and add Al-Cu master alloy;

[0078] (2) The melt temperature is further raised to 740°C, Al-Zr, Al-Ti, Al-Y, and Al-Si master alloys are added, and potassium chloride is used for the first refining;

[0079] (3) Continue to reduce the melt temperature to 690°C, then add pure Zn and pure Mg, and perform a second refining using nitrogen;

[0080] (4) The melt is heated to 730°C, Al-Co and Al-Nb master alloys are added, stirred for 2-5 minutes, and then allowed to stand for 5-10 minutes; when the temperature drops to 720°C, stirred until a semi-solid metal liquid is formed, and then cast to obtain the alloy.

[0081] A train built-in bogie anti-snake shock absorber seat is made of the above alloy, and the specific process is as follows:

[0082] (1) Casting alloy ingot: The alloy ingot is prepared by the above method.

[0083] (2) Homogenization treatment: remove the outer skin of the alloy ingot obtained in step (1), heat to 380°C and keep it for 12 h, then continue to heat to 490°C and keep it for 20 h, and cool it with water at room temperature.

[0084] (3) Hot extrusion: The alloy billet obtained in step (2) is heated to 450°C and kept at this temperature for 4 hours, and then hot extruded. The preheating temperature of the extrusion barrel is 380°C, and the extrusion ratio is ≥10.

[0085] (4) Preheating: Heat the alloy extrusion billet obtained in step (3) to 380°C and keep it warm for 2-6 hours.

[0086] (5) Superplastic die forging: The alloy blank obtained in step (4) is placed in a pre-forging die for superplastic die forging to obtain an alloy shock absorber seat forging blank. The die preheating temperature is 450°C, the die forging temperature is 450°C, and the die forging rate is 10×10 - 5 mm / s.

[0087] (6) Superplastic die forging final forging: The alloy billet obtained in step (5) is placed in a final forging die for superplastic die forging to obtain an alloy shock absorber seat forging billet. The die preheating temperature is 450°C, the die forging temperature is 380°C, and the die forging rate is 10×10 - 5 mm / s.

[0088] (7) Rough machining: The alloy shock absorber seat forging blank obtained in step (6) is rough machined according to the shock absorber seat rough machining drawing.

[0089] (8) Heat treatment: The rough-machined alloy shock absorber seat obtained in step (7) is heated to 500° C. and kept at this temperature for 3 h, and then water-cooled at room temperature; then heated to 140° C. and kept at this temperature for 26 h, and then air-cooled.

[0090] (9) Finishing: The alloy shock absorber seat obtained in step (8) is finished according to the shock absorber seat finishing drawing.

[0091] Comparative Example 1

[0092] Compared with Example 1, the Mn element is used to replace the Co element in the formula, and the rest of the process is consistent with Example 1.

[0093] Comparative Example 2

[0094] Compared with Example 1, the Cd element is used to replace the Nb element in the formula, and the rest of the process is consistent with Example 1.

[0095] Comparative Example 3

[0096] Compared with Example 1, the formula lacks Si, Mg, Co and Nb elements, and the rest of the process is consistent with Example 1.

[0097] Comparative Example 4

[0098] Compared with Example 1, in step (4) of alloy preparation, stirring is not performed before pouring, and a semi-solid molten metal is not obtained. The rest of the process is consistent with Example 1.

[0099] The shock absorber seats prepared in Examples 1 to 3 and Comparative Examples 1 to 4 were tested for tensile strength, yield strength and elongation. The results are shown in Table 1.

[0100] Table 1 Performance test

[0101]

[0102]

[0103] According to the test data in Table 1, the mechanical properties such as tensile strength, yield strength and elongation after fracture of the products prepared in Examples 1 to 3 of the present invention are significantly better than those in the comparative examples, especially Example 1, which is significantly better than Comparative Examples 1, 3 and 4. It can be seen that only under the technical scheme defined in the present invention can alloy products with excellent mechanical properties be prepared.

[0104] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. An alloy for preparing an anti-snaking shock absorber seat for a train built-in bogie, characterized in that: The composition comprises the following components in parts by weight: Zn 5-8%, Mg 1.5-3%, Cu 2.0-5%, Zr 0.1-0.5%, Ti 0.04-0.5%, Y 0.05~0.5%, Si 2.5~4.5%, Co 0.05~0.5%, Nb 0.1~0.5%, and the rest are Al and unavoidable impurities.

2. The alloy for preparing the anti-snake shock absorber seat of the train built-in bogie according to claim 1, characterized in that: The composition comprises the following components in parts by weight: Zn 5.8-7.6%, Mg 1.5-1.9%, Cu 2.0-2.5%, Zr 0.1-0.2%, Ti 0.04-0.12%, Y0.05~0.35%, Si 3~4.5%, Co 0.1~0.5%, Nb 0.1~0.5%, and the rest are Al and unavoidable impurities.

3. The alloy for preparing the anti-snaking shock absorber seat of the train built-in bogie according to claim 2, characterized in that: The composition comprises the following components in parts by weight: Zn 6%, Mg 1.5%, Cu 2.5%, Zr 0.1%, Ti 0.1%, Y 0.1%, Si 4.5%, Co 0.5%, Nb 0.1%, and the rest are Al and inevitable impurities.

4. The alloy for preparing the anti-snaking shock absorber seat of the train built-in bogie according to any one of claims 1 to 3, characterized in that: The total amount of the inevitable impurities is controlled to be 0.05-0.15% by weight, and the content of each impurity in the inevitable impurities is ≤0.05% by weight.

5. The alloy for preparing the anti-snaking shock absorber seat of the train built-in bogie according to claim 4, characterized in that: The inevitable impurities include at least one of Ca, V, P, Fe, and Mn.

6. A method for preparing the alloy according to any one of claims 1 to 5, characterized in that: The following steps are involved: (1) pure Al is heated and melted, then the melt temperature is raised to 680°C-700°C, and Al-Cu master alloy is added; (2) Continue to raise the melt temperature to 720-740°C, add Al-Zr, Al-Ti, Al-Y, and Al-Si master alloys, and perform the first refining; (3) Continue to lower the melt temperature to 690-710°C, then add pure Zn and pure Mg, and perform a second refining; (4) The melt is heated to 720-730°C, Al-Co and Al-Nb master alloys are added, stirred for 2-5 minutes, and then allowed to stand for 5-10 minutes; when the temperature drops to 710-720°C, stirred until a semi-solid metal liquid is formed, and then cast to obtain the alloy.

7. The method according to claim 6, characterized in that In step (2) and step (3), refining is performed using a refining agent and / or a refining gas.

8. The method according to claim 7, characterized in that The refining agent is chloride salt, and the refining gas is inert gas.

9. A train built-in bogie anti-snake shock absorber seat, characterized in that: The alloy according to any one of claims 1 to 5 is used, and the specific process is as follows: (1) Casting the alloy according to any one of claims 1 to 5 to form a casting billet and removing the outer skin, heating to 380-450° C. and keeping the temperature for 8-14 hours, then continuing to heat to 450-490° C. and keeping the temperature for 20-26 hours, and cooling with water at room temperature; (2) heating the treated alloy billet to 380-450°C for 2-6 hours, and then hot extruding, with the preheating temperature of the extrusion barrel being 380-450°C and the extrusion ratio being ≥10; (3) heating the alloy extrusion billet obtained in step (2) to 380-450° C. and keeping the temperature for 2-6 hours; (4) The alloy blank obtained in step (3) is subjected to superplastic die forging, wherein the die preheating temperature is 380-450°C, the die forging temperature is 380-450°C, and the die forging rate is 10×10 -5 ~10×10 -2 mm / s, and the pre-cut alloy shock absorber forging blank is obtained; (5) The alloy shock absorber seat forging blank obtained in step (4) is subjected to superplastic die forging final forging, the die preheating temperature is 380-450°C, the die forging temperature is 380-450°C, and the die forging rate is 10×10 -5 ~10×10 -2 mm / s, and the alloy shock absorber seat forging blank with final forging treatment is obtained; (6) The alloy shock absorber seat forging blank obtained in step (5) is subjected to rough processing, heat treatment and fine processing in sequence to obtain the integral shock absorber seat for the built-in bogie of the train.

Images