Continuous casting and continuous forging method for smelting metal by using electron beam cold bed furnace

Abstract

The invention discloses a continuous casting and continuous forging method for smelting metal by using an electron beam cold bed furnace, which is characterized in that a process for smelting the metal by using the electron beam cold bed furnace is improved, the temperature is directly increased to the temperature required by cast ingot forging in an ingot chamber and maintained for a preset time for constant-temperature treatment, and the cast ingot subjected to the constant-temperature treatment can be directly cast and processed. And the forging time of the product is greatly shortened, and the efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of casting, and in particular to a method for continuous casting and forging of metal by using an electron beam cooling hearth furnace. Background Art

[0002] As the market demands for material performance increase, vacuum electron beam cold hearth melting furnaces have been widely used in materials such as refractory metals such as titanium germanium, high temperature metals such as tantalum, niobium and molybdenum, and high temperature alloys based on their own advantages. However, there is a fatal problem with the casting ingots melted in vacuum electron beam furnaces: the metal grain size is uneven, which directly leads to the inability of the produced materials to be directly used in the back-end industry and requires a forging process to complete the change of metal properties.

[0003] The current method is to cool the metal ingot melted in the electron beam furnace and then process it, and then heat it forge it. In this process, the cooling of the ingot, machining, and heating before forging all take a lot of time. The production cycle of the entire process is too long and the efficiency is low, which needs to be improved. Summary of the invention

[0004] To solve at least one of the above technical defects, the present invention provides the following technical solutions: The present application document discloses a method for continuous casting and forging of metal using an electron beam cooling furnace, comprising the following steps: First, the required components of the product metal are melted and cast into ingots using an electron beam cooling furnace; Second, the ingot is treated at a constant temperature, where the temperature is raised to the required temperature for ingot casting in the electron beam cooling furnace ingot chamber and maintained for a predetermined time; Third, the ingot is taken out from the ingot chamber for forging.

[0005] Furthermore, the required components of the product metal are melted into a molten metal in an electron beam cooling furnace, and the molten metal is cast into a corresponding mold, and a crucible is used to cool the molten metal while casting until the ingot is solidified.

[0006] Furthermore, when melting and casting titanium, the cooling rate is 200-400°C / h; when melting and casting copper, the cooling rate is 300-600°C / h.

[0007] Furthermore, in the second step, the constant temperature is maintained for more than 2.5 hours when melting and casting titanium; and the constant temperature is maintained for less than 4 hours when melting and casting copper.

[0008] Furthermore, in the second step, the heating rate in the ingot chamber is 700-850° C. / h.

[0009] Furthermore, the method also includes the step of cutting off the head, cooling the product formed after forging, and cutting off the head portion of the cooled product.

[0010] Compared with the prior art, the present invention has the following beneficial effects: The present invention improves the process of melting and casting metal in an electron beam cooling hearth furnace, directly raises the temperature in the ingot chamber to the temperature required for ingot forging and maintains it for a predetermined time for constant temperature treatment. After the constant temperature treatment, the ingot can be directly cast, reducing the cooling time in the electron beam cooling hearth furnace, greatly shortening the forging processing time of the product and improving the efficiency.

[0011] The present invention performs a constant temperature treatment on the ingot in the ingot chamber, and the ingot can be directly forged after the constant temperature treatment. The electron beam cooling bed furnace and the forging equipment are produced in a one-to-one manner, which greatly improves the production capacity and the equipment utilization rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0013] Figure 1 is a crystal phase structure diagram of the products in Example 1 and Comparative Example 1; Figure 2 is a crystal phase structure diagram of the products in Example 2 and Comparative Example 2; in: Figure 1 (a) is a crystal phase structure diagram of the product prepared in Comparative Example 1; Figure 1 (b) is the crystal structure diagram of the product prepared in Example 1; Figure 2 (a) is the crystal phase structure diagram of the product prepared in Comparative Example 2; Figure 2 (b) is the crystal phase structure diagram of the product prepared in Example 2. DETAILED DESCRIPTION

[0014] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0015] Example 1 A method for continuous casting and forging of metal using an electron beam cooling furnace comprises the following steps: First, the electron beam cooling furnace is used to melt and cast the required components of the product metal into an ingot. In this example, the product metal is titanium metal, and the component ratio is: titanium metal with a purity of more than 99.9%. The parameters of the electron beam cooling furnace are as follows: vacuum degree 10-1, electron gun power 300KW, the required components of the product metal are melted into molten metal and then cast into the required mold, and a round crucible is used for casting and cooling at the same time, the cooling rate is 300℃ / h, the ingot pulling speed is 250Kg / h, and the molten metal solidifies into an ingot.

[0016] Second, the ingot is treated at a constant temperature. The temperature in the ingot chamber of the electron beam cooling furnace is raised to 950°C, which is the temperature required for product forging. The heating rate is 800°C / h, and the constant temperature is maintained for 4 hours.

[0017] Third, the ingot is taken out of the ingot chamber for forging. The forging parameters are as follows: three forgings at 950°C, two piercings and three drawing, and finally the forged ingot is rounded and straightened at 600°C.

[0018] Fourth, cut off the protrusion, allow the forged product to cool down naturally, calculate the protrusion part of the product and cut it off.

[0019] Comparative Example 1 The difference from Example 1 is that in this example, in the step of constant temperature treatment in the ingot-free chamber, the molten metal solidifies and forms an ingot, which is gradually cooled for 12 hours. The ingot is taken out for machining (the ingot is cut and separated from the tooling, and the casting shrinkage surface is turned and peeled), which takes 24 hours. The product formed after machining is heated up, which takes 12 hours. After heating, forging is carried out, and the heating rate and forging parameters are consistent with those in Example 1.

[0020] Example 2 A method for continuous casting and forging of metal using an electron beam cooling furnace comprises the following steps: First, the electron beam cooling furnace is used to melt and cast the required components of the product metal into ingots. In this example, the product metal is copper, and the component ratio is copper material with a purity of more than 99.99%. The parameters of the electron beam cooling furnace are as follows: vacuum degree 10-2, electron gun power 500KW, the required components of the product metal are melted into molten metal and then cast into the required mold, and a round crucible is used for casting and cooling at the same time, the cooling rate is 600℃ / h, the ingot pulling speed is 300Kg / h, and the molten metal solidifies into an ingot.

[0021] Second, the ingot is treated at a constant temperature. The temperature in the ingot chamber of the electron beam cooling furnace is raised to 850°C, which is the temperature required for product forging. The heating rate is 700°C / h, and the constant temperature is maintained for 3 hours.

[0022] Third, the ingot is taken out of the ingot chamber for forging. The forging parameters are as follows: two piers and two pulls at 850°C, and finally the mold is rounded and straightened at 600°C.

[0023] Fourth, cut off the protrusion, allow the forged product to cool down naturally, calculate the protrusion part of the product and cut it off.

[0024] Comparative Example 2 The difference from Example 2 is that in this example, in the step of constant temperature treatment in the ingot-free chamber, the molten metal solidifies and forms an ingot, which is gradually cooled for 16 hours. The ingot is taken out for machining (the ingot is cut and separated from the tooling, and the casting shrinkage surface is turned and peeled), which takes 24 hours. The product formed after machining is heated for 12 hours and forged after heating. The heating rate and forging parameters are consistent with those in Example 2.

[0025] The products prepared in the above examples and comparative examples were tested, as shown in the attached drawings. Figure 1 (a) is the crystal phase diagram of comparative example 1 (i.e., traditional process) after forging. Figure 1 (b) is the crystal phase diagram after forging by the process of the present invention in Example 1. It can be seen that the crystal phase after forging by this process is more uniform and delicate, and can better meet customer requirements. Figure 2 (a) is the crystal phase diagram of comparative example 2 (i.e., traditional process) after forging. Figure 2 (b) is the crystal phase diagram after forging by the process of the present invention in Example 2. Due to the large diameter of the ingot, the traditional process often has the above-mentioned left-side grain situation, which is insufficient in uniformity and cannot meet the customer's usage requirements. The crystal phase after forging by the process of the present invention is more uniform and delicate, and can better meet customer requirements.

[0026] The above are only preferred embodiments of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A method for continuous casting and forging of metal using an electron beam cooling furnace, characterized in that: The following steps are involved: First, the required components of the product metal are melted and cast into ingots using an electron beam cooling furnace; Second, the ingot is treated at a constant temperature, where the temperature is raised to the required temperature for ingot casting in the electron beam cooling furnace ingot chamber and maintained for a predetermined time; Third, the ingot is taken out from the ingot chamber for forging.

2. A method for continuous casting and forging of metal using an electron beam cooling furnace as claimed in claim 1, characterized in that: The required components of the product metal are melted into a molten metal in an electron beam cooling furnace, and the molten metal is cast into a corresponding mold, and the crucible is used to cool while casting until the ingot is solidified.

3. A method for continuous casting and forging of metal using an electron beam cooling furnace as claimed in claim 2, characterized in that: When melting and casting titanium, the cooling rate is 200-400℃ / h; when melting and casting copper, the cooling rate is 300-600℃ / h.

4. The method for continuous casting and forging of metal using an electron beam cooling furnace as claimed in claim 1, characterized in that: In the second step, the constant temperature is maintained for more than 2.5 hours when melting and casting titanium; and the constant temperature is maintained for less than 4 hours when melting and casting copper.

5. The method for continuous casting and forging of metal using an electron beam cooling furnace as claimed in claim 1, characterized in that: In the second step, the heating rate in the ingot chamber is 700-850°C / h.

6. The method for continuous casting and forging of metal using an electron beam cooling furnace as claimed in claim 1, characterized in that: It also includes a machining step, in which the product formed after forging is cooled, the protruding part of the cooled product is cut off, and then machining is performed.

Images