A method for melting and casting TA10 titanium alloy in a hot cathode electron gun EB furnace

Abstract

This invention provides a method for melting and casting TA10 titanium alloy in a hot cathode electron gun EB furnace, specifically including: (1) constructing a simulation model using numerical simulation technology to simulate the temperature distribution of the molten pool surface in the cooling bed and crystallizer; (2) using the simulation model to simulate the temperature distribution of the molten pool surface in the cooling bed and crystallizer of the hot cathode electron gun EB furnace when melting and casting TA10 titanium alloy at a set melting rate v, and calculating the volatilization rate distribution of Ni element using the following formula: for Q i Integrate to obtain the total amount of Ni volatilized per unit time in the cooling bed and crystallizer during the smelting process, Q; (3) Calculate the amount of Ni added: Amount of Ni added = Target value of composition control + Q / v; (4) Use the calculated amount of Ni added as the actual amount of Ni added in the raw material ratio to produce TA10 titanium alloy. The technical solution of the present invention can make up for the loss of Ni during the smelting process and smelt TA10 products with a composition range that meets the national standard requirements.

Description

Technical Field

[0001] This invention relates to the field of titanium alloy EB furnace casting, and more particularly to a method for casting TA10 titanium alloy in a hot cathode electron gun EB furnace. Background Technology

[0002] TA10 titanium alloy has a composition of Ti-0.8Ni-0.3Mo and belongs to the near-α type titanium alloy. Due to its excellent corrosion resistance, it is widely used in metallurgy, shipbuilding, and marine engineering. There is a large market demand for TA10 grade plates and coils, with high performance requirements. Currently, the main smelting methods for TA10 titanium alloy in China are vacuum arc remelting furnaces (VAR furnaces) and electron beam cold hearth furnaces (EB furnaces), with VAR smelting being the primary method for producing TA10. VAR smelting of TA10 titanium alloy typically requires 2-3 smelting processes, and it is difficult to fully remove high- and low-density inclusions introduced by the raw materials or welding process. The process involves pressing electrodes before smelting, welding, multiple smelting processes, and forging, resulting in low metal yield and high production costs. EB furnace smelting can effectively solve this problem. EB furnaces only require one smelting process to produce titanium flat ingots that meet the requirements of downstream rolling processes, reducing the need for pressing electrodes, multiple smelting processes, and forging, thus significantly reducing production costs.

[0003] Based on the characteristics of the electron gun, electron beam (EB) furnaces can be divided into hot cathode electron gun EB furnaces and cold cathode electron gun EB furnaces. Hot cathode electron guns typically use tungsten-tantalum alloy as the electron emission source, and their vacuum requirements are high, with the vacuum level in the gun chamber needing to be less than 10. -4 The vacuum level during the melting process is typically between 0.01 and 0.1 Pa. The cold cathode electron gun uses aluminum alloy as the cathode and is heated by electron bombardment generated by hydrogen ionization. The cold cathode electron gun is connected to the melting chamber, and its vacuum requirement is lower; a vacuum level greater than 1 Pa is sufficient for normal melting. In existing technologies, the difference in vacuum level during the melting process has a significant impact on the loss of Ni element in TA10, directly affecting the EB furnace melting effect of TA10. Summary of the Invention

[0004] To address the technical problems existing in the prior art, the present invention provides a method for melting and casting TA10 titanium alloy in a hot cathode electron gun EB furnace.

[0005] The technical means employed in this invention are as follows:

[0006] A method for melting and casting TA10 titanium alloy in a hot cathode electron gun EB furnace specifically includes the following steps:

[0007] (1) A simulation model was constructed using numerical simulation technology to simulate the temperature distribution of the molten pool surface in the cooling bed and crystallizer when melting TA10 titanium alloy in the EB furnace with hot cathode electron gun.

[0008] (2) A simulation model was used to simulate the temperature distribution of the molten pool surface in the cooling bed and crystallizer of the hot cathode electron gun EB furnace when TA10 titanium alloy was melted at a set melting rate v (kg / h). Based on the temperature distribution of the molten pool surface, the volatilization rate distribution of Ni in the cooling bed and crystallizer during the melting process was calculated using the following formula:

[0009]

[0010] In the formula: Q i For the area element S i The volatilization rate of Ni in the molten pool is kg / s; S is the area of ​​the molten pool, m; α is the activity of Ni; P is the saturated vapor pressure of Ni; M is the relative molecular mass of Ni; T is the area element S. i The temperature of the molten pool surface inside;

[0011] Using the following formula for Q i Integrating, we obtain the total amount of Ni volatilized per unit time, Q (kg / h), in the cooling bed and crystallizer during the smelting process: Q = 3600 × ∑Q i ;

[0012] (3) Calculate the amount of Ni element according to the following formula: Amount of Ni element = Target value of composition control + Q / v, where the target value of composition control refers to the expected target value of Ni element in the produced TA10 product;

[0013] (4) The calculated amount of Ni element is used as the actual amount of Ni element added in the raw material ratio for the production of TA10 titanium alloy.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] The present invention provides a method for melting and casting TA10 titanium alloy in a hot cathode electron gun EB furnace. A simulation model is constructed using numerical simulation technology, and the amount of Ni volatilization per unit time is calculated based on the simulation model and the melting rate. Then, the amount of Ni added is calculated. By using the amount of Ni added as the amount of Ni added in the raw material ratio, the loss of Ni during the melting and casting of TA10 titanium alloy can be compensated, and TA10 products with a composition range that meets the national standard requirements can be melted.

[0016] Based on the above reasons, this invention can be widely promoted in the field of TA10 titanium alloy casting. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the C-type cold bed hot cathode EB furnace described in this invention.

[0019] Figure 2 This shows the temperature distribution of the molten pool surface in the primary refining cooling bed and the refining cooling bed in Example 1.

[0020] Figure 3 This shows the temperature distribution of the molten pool surface in the crystallizer in Example 1.

[0021] Figure 4 The distribution of Ni volatilization rate in the primary refining cold bed and the refining cold bed in Example 1.

[0022] Figure 5 The distribution of Ni volatilization rate in the crystallizer in Example 1.

[0023] In the diagram: 1. Primary refining cooling bed; 2. Refining cooling bed; 3. Crystallizer. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Example 1

[0026] This invention provides a method for melting and casting TA10 titanium alloy in a hot cathode electron gun EB furnace, specifically including the following steps:

[0027] (1) A simulation model was constructed using numerical simulation technology to simulate the temperature distribution of the molten pool surface in the cooling bed and crystallizer when melting TA10 titanium alloy in the EB furnace with hot cathode electron gun.

[0028] (2) A simulation model was used to simulate the temperature distribution of the molten pool surface in the cooling bed and crystallizer of the hot cathode electron gun EB furnace when melting and casting TA10 titanium alloy at a set melting rate v (kg / h). Figure 2 and Figure 3 As shown), and based on the temperature distribution of the molten pool surface, the volatilization rate distribution of Ni in the cooling bed and crystallizer during the smelting process is calculated using the following formula (e.g. Figure 4 and Figure 5 As shown):

[0029]

[0030] In the formula: Q i For the area element S i The volatilization rate of Ni in the molten pool is kg / s; S is the area of ​​the molten pool, m; α is the activity of Ni; P is the saturated vapor pressure of Ni; M is the relative molecular mass of Ni; T is the area element S. i The temperature of the molten pool surface inside;

[0031] Using the following formula for Q i Integrating, we obtain the total amount of Ni volatilized per unit time, Q (kg / h), in the cooling bed and crystallizer during the smelting process: Q = 3600 × ∑Q i ;

[0032] (3) Calculate the amount of Ni element according to the following formula: Amount of Ni element = Target value of composition control + Q / v, where the target value of composition control refers to the expected target value of Ni element in the produced TA10 product;

[0033] (4) The calculated amount of Ni element is used as the actual amount of Ni element added in the raw material ratio. TA10 titanium alloy is produced by melting and casting in a hot cathode electron gun EB furnace, thereby producing TA10 titanium alloy products with a composition range that meets the national standard requirements.

[0034] Furthermore, when constructing a simulation model using a numerical simulation system in the existing technology, the melting process parameters for casting TA10 titanium alloy using a hot cathode electron gun EB furnace include: melting rate, melting power of the electron gun, scanning patterns of different electron guns, dwell time and energy distribution, inlet and outlet water temperature difference and flow rate of cooling water, and furnace wall (condenser hood) temperature.

[0035] Furthermore, the smelting process used for melting and casting TA10 titanium alloy in the hot cathode electron gun EB furnace can be the existing process method for melting pure titanium TA1 or TA2 ingots in the hot cathode electron gun EB furnace, which will not be elaborated upon in this invention.

[0036] Furthermore, the method can be adopted as follows: Figure 1The C-type cold bed hot cathode electron gun EB furnace shown includes a rectangular primary refining cold bed 1, an L-type refining cold bed 2 capable of double-pulling ingots, two rectangular crystallizers 3, and four hot cathode electron guns. Among the four hot cathode electron guns, hot cathode electron guns #1 and #2 are responsible for melting raw materials and reheating the primary refining cold bed 1, hot cathode electron gun #3 is responsible for reheating the refining cold bed 2, and hot cathode electron gun #4 is responsible for reheating the rectangular crystallizer 3.

[0037] By using the amount of Ni element obtained by the method described in this invention as the actual amount of Ni element added in the raw material ratio for casting TA10 titanium alloy, the loss of Ni element during the smelting process can be compensated, which is more conducive to achieving the control target of Ni composition.

[0038] After the method of the present invention is implemented in the EB furnace production line of Panzhihua Iron and Steel Group, TA10 titanium flat ingots with qualified composition can be melted and cast in one go, enriching the product variety of EB billets. The method of the present invention can be promoted and used in EB furnace manufacturers.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for melting and casting TA10 titanium alloy in a hot cathode electron gun EB furnace, characterized in that, Specifically, the following steps are included: (1) A simulation model was constructed using numerical simulation technology to simulate the temperature distribution of the molten pool surface in the cooling bed and crystallizer when melting TA10 titanium alloy in the EB furnace with hot cathode electron gun. (2) The temperature distribution of the molten pool surface in the cooling bed and crystallizer of the hot cathode electron gun EB furnace was simulated using a simulation model when TA10 titanium alloy was melted at a set melting rate v (kg / h). Based on the temperature distribution of the molten pool surface, the volatilization rate distribution of Ni in the cooling bed and crystallizer during the melting process was calculated using the following formula: ； In the formula: Q i For area infinitesimal element S i The volatilization rate of Ni within the element, kg / s; α is the activity of Ni; P is the saturated vapor pressure of Ni; M is the relative molecular mass of Ni; T is the area element. S i The temperature of the molten pool surface inside; Using the following formula Q i By integrating, the total amount of Ni volatilized per unit time in the cooling bed and crystallizer during the smelting process can be obtained. Q (kg / h): ; (3) Calculate the amount of Ni element according to the following formula: Amount of Ni element = Target value of composition control + Q / v, where the target value of composition control refers to the expected target value of Ni element in the produced TA10 product; (4) The calculated amount of Ni element is used as the actual amount of Ni element added in the raw material ratio for the production of TA10 titanium alloy.

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