A method for improving the surface quality of titanium or titanium alloy EB ingot

Abstract

The application discloses a method for improving the surface quality of titanium or titanium alloy EB ingot, which adopts crystallizer region electron beam scanning pattern multi-layer superposition design, namely, on the basis of a main pattern of a crucible of the crystallizer region, a border line pattern of a peripheral edge part is superposed, so that the electron beam input energy of titanium liquid in contact with a water-cooled copper crucible crystallizer is improved, the titanium liquid temperature of the edge part is improved, the influence of the chilling action is reduced, and the titanium liquid is better filled; the design of the application is also aimed at reducing the temperature gradient from the center of the ingot to the edge part, improving the temperature uniformity degree of the cross section of the ingot in the crystallization region, obtaining a relatively gentle solid-liquid phase line, and improving the ingot quality. In addition, the border line superposition energy can reach the purpose of improving the influence of the condensate in the upper edge inner wall of the crystallizer on the ingot surface quality.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of titanium or titanium alloy smelting processing, and particularly relates to a method for improving the surface quality of titanium or titanium alloy EB ingot. BACKGROUND

[0002] Titanium and titanium alloy have high specific strength, corrosion resistance, good biocompatibility and other advantages, and have broad application prospects in the fields of aerospace, shipbuilding, chemical industry, biological medicine, transportation and sports leisure. However, the high cost of titanium materials limits its further popularization and application. Reducing the smelting and blanking cost of titanium and titanium alloy is the main research direction of the industry. Electron beam cold bed (EB) smelting is a smelting method that uses high-voltage accelerated electrons and controls the path and range through focusing and deflection magnetic field to convert high-speed electrons hitting the metal surface into heat energy, so that the metal is melted. Through the cold bed structure, the three processes of raw material melting, refining and crucible crystallization are separated, the electron gun can be independently controlled, and the shaped section ingot can be produced. At the same time, this method has the advantages of high vacuum degree, short process, low cost, high purity, high production efficiency and the like.

[0003] In the process of titanium and titanium alloy electron beam cold bed smelting, the titanium metal raw material is melted into titanium liquid under the action of the electron beam. The molten titanium liquid flows into the water-cooled copper crucible crystallizer with strong cooling effect through the melting cold bed and the refining cold bed. Because the edge part of the crucible in contact with the titanium liquid has strong chilling effect, and the titanium liquid has poor filling performance, surface defects such as cold shut, subsurface shrinkage hole and the like are easily formed on the surface of the EB ingot. At the same time, in the process of continuous smelting, in order to avoid the risk of titanium liquid overflow, the titanium liquid surface is lower than the upper end surface of the crystallizer, and titanium metal vapor is easy to form and accumulate condensate on the inner wall of the upper edge of the crystallizer, which may be wrapped into the surface of the titanium liquid close to the side wall of the crystallizer, resulting in surface inclusion defects of the ingot. The above-mentioned cold shut, subsurface shrinkage hole and inclusion defects of the EB ingot directly affect the quality of the titanium and titanium alloy EB ingot. How to improve the surface quality of the EB ingot is an urgent problem to be solved in the industry.

[0004] The surface defects such as cold shut, shrinkage hole and inclusion of the ingot on one hand increase the machining removal amount of the ingot surface, and on the other hand induce the risk of cracks in the subsequent hot working. The improvement of the surface defects not only improves the material yield, but also promotes the stability of the internal quality of the processed material. Therefore, the surface quality is an important control requirement in the industry. In order to improve the quality of the electron beam cold bed smelting ingot, the industry generally adjusts the smelting and ingot drawing process parameters, electron beam scanning methods and the like to improve the surface quality.

[0005] CN201410430284.8 discloses a method for improving the surface quality of EB furnace production of giant flat titanium billet, mainly through the adjustment of process parameters such as changing the ingot drawing speed. CN201911013813.3 discloses a surface crack control method for preparing titanium and titanium alloy ingots by electron beam cold bed furnace, which eliminates the surface cracks of the ingots and improves the ingot yield by controlling the upward reverse pushing distance, reverse pushing frequency, melting speed and other parameters. In the design of electron beam scanning pattern (or scanning pattern, scanning track), CN201410430803.0 discloses a scanning method for maintaining the temperature uniformity of the rectangular crystallizer of the electron beam cold bed furnace, which divides the length direction of the crystallizer scanning area into several equal parts, sets the scanning pattern and performs thermal imaging and temperature measurement to improve the surface quality of the ingot.

[0006] The existing disclosed technical documents do not aim at the chilling effect of the edge of the electron beam cold bed melting crystallizer, and the surface defects such as surface cold separation, subcutaneous shrinkage hole and surface inclusion are easily formed, so the multi-layer superposition design of the scanning pattern is adopted. SUMMARY

[0007] The purpose of the present application is to provide a method for improving the surface quality of titanium and titanium alloy EB ingots, which adopts multi-layer superposition design of the crystallizer area electron beam scanning pattern, improves the electron beam input energy of the titanium liquid in contact with the water-cooled copper crucible crystallizer, improves the edge titanium liquid temperature, reduces the influence of chilling effect, and promotes better filling of titanium liquid; The design of the present application also aims to reduce the temperature gradient from the center to the edge of the ingot, improve the temperature uniformity of the cross section of the crystallization area of the ingot, obtain a relatively gentle solid-liquid phase line, and improve the quality of the ingot. In addition, the edge line superposition energy is used to improve the influence of the condensate in the upper edge of the crystallizer on the surface quality of the ingot.

[0008] In order to achieve the above purpose, the present application adopts the following technical scheme.

[0009] A method for improving the surface quality of titanium or titanium alloy EB ingots is provided, comprising the following steps:

[0010] (1) Put the titanium or titanium alloy raw material into the feeder, and perform electron beam cold bed preheating and melting;

[0011] (2) The electron beam scanning pattern of the crucible crystallizer area is set as follows: on the basis of the main pattern of the crucible crystallizer area, the edge line pattern of the four surrounding edges is superimposed, the electron beam input energy of the titanium liquid in contact with the crucible crystallizer is improved, and the temperature of the edge liquid is increased;

[0012] (3) The titanium or titanium alloy raw material is melted and flows to the flow channel until the flow channel is interrupted, all side line patterns are closed, the main pattern of the crucible crystallizer area is retained, and the emission current is gradually reduced over time, the area of the main pattern of the crucible crystallizer area is gradually reduced, the ingot hot top is completed, and the ingot is discharged after cooling.

[0013] As a further description of the present application, the titanium or titanium alloy raw material is loaded into the feeder in step (1), and electron beam cold bed preheating and melting are performed, which includes:

[0014] (101) The titanium or titanium alloy raw material is loaded into the feeder, vacuumized to meet the starting gun condition, and the electron gun is opened to preheat the melting cold bed, the refining cold bed, and the overflow cold bed area. After the shell is fully melted, the preheating is completed.

[0015] (102) The titanium or titanium alloy raw material is melted and discharged, and the fresh titanium liquid enters the molten pool, gradually fills the melting cold bed, the refining cold bed, the overflow cold bed, and the crucible crystallizer, and enters the normal melting stage.

[0016] As a further description of the present application, the main pattern in step (2) is based on the main pattern in the crucible crystallizer area, and the side line pattern of the four peripheral parts is superimposed, which includes:

[0017] The main pattern covers the crucible crystallizer area, and the ingot near end is provided with a scanning pattern with a width same as the main pattern and a length of 5% to 20% of the length of the main pattern, which is coincided with the main pattern and close to the near overflow port end line of the main pattern, defining the near end line pattern; the ingot far end is provided with a scanning pattern with a width same as the main pattern and a length of 5% to 25% of the length of the main pattern, which is coincided with the main pattern and close to the ingot far end line of the main pattern, defining the far end line pattern.

[0018] As a further description of the present application, the main pattern in step (2) is based on the main pattern in the crucible crystallizer area, and the side line pattern of the four peripheral parts is superimposed, which includes:

[0019] The upper and lower edges inside the crucible crystallizer area are provided with scanning patterns with a width of 5% to 18% of the width of the main pattern and a length same as the main pattern, which are respectively close to the upper and lower edges of the main pattern, defining the upper and lower line patterns.

[0020] As a further description of the present application, the scanning duration of the near end line pattern is 30-80 ms; the scanning duration of the far end line pattern is 20-100 ms; and the scanning duration of the upper and lower line patterns is 60-220 ms.

[0021] As a further explanation of the present invention, the emission current in step (3) is reduced to 0; the area of ​​the main pattern in the crucible crystallizer region is reduced to 50%.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] The present invention provides a method for improving the surface quality of titanium and titanium alloy EB ingots. By designing the electron beam pattern of the crystallization region, the influence of quenching is reduced, the temperature of the ingot cross section is made uniform, the liquid level is kept stable, and the condensate trapped at the edge is fully dissolved, thereby improving surface defects such as cold shuts and inclusions in the ingot and increasing the yield of ingot processing.

[0024] (1) By superimposing the edge pattern of the four sides on the main pattern of the crucible crystallizer area, the temperature of the titanium liquid at the edge is relatively increased, which promotes the filling of the titanium liquid and avoids the quenching effect adjacent to the crystallizer, effectively improving the casting defects caused by surface cold shuts, cracking and other casting defects during the casting process.

[0025] (2) By superimposing the edge pattern, it has a higher energy than the main pattern, which can better remove the condensate that occasionally gets trapped in the molten pool on the inner wall of the upper edge of the crystallizer, and avoid the formation of insoluble substances or inclusions in the ingot.

[0026] (3) By superimposing the edge lines, designing appropriate graphic range and dwell time parameters, and rationally formulating energy distribution, the temperature of the melt to be solidified in the crucible becomes more uniform, the solid-liquid two-phase line becomes smoother, the solidification process of the outer side and the core of the ingot tends to be synchronized, and the internal quality of the ingot is improved.

[0027] This invention, through improvements to the electron beam process, can significantly improve the surface quality of ingots, reduce the proportion of surface defects, and decrease the amount of milling and grinding required, thereby increasing yield and production efficiency. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the electron beam scanning pattern of the crucible crystallizer region in this invention.

[0029] Figure 2 This is a schematic diagram of the crucible crystallizer area in electron beam cold bed melting according to the present invention.

[0030] Figure 3 The surface state of the EB ingot obtained in Comparative Example 1 of this invention is shown.

[0031] Figure 4 This is the surface state of the EB ingot obtained in Example 1 of the present invention.

[0032] Explanation of reference numerals in the attached figures:

[0033] 1, main pattern; 2, proximal edge line pattern; 3, lower edge line pattern; 4, distal edge line pattern; 5, upper edge line pattern; 6, electron gun; 7, electron beam pattern; 8, crucible crystallizer; 9, molten pool; 10, ingot. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0035] The embodiments of the present application provide a method for improving the surface quality of titanium or titanium alloy EB ingot, comprising the following steps:

[0036] (1) loading titanium or titanium alloy raw materials into a feeder, and performing electron beam cold bed preheating and smelting;

[0037] (2) setting the electron beam scanning pattern of the crucible crystallizer region as follows: on the basis of the main pattern of the crucible crystallizer region, superimposing the edge line patterns of the four peripheral parts, so as to increase the electron beam input energy of the titanium liquid in contact with the crucible crystallizer, and increase the temperature of the liquid in the edge part;

[0038] (3) after the titanium or titanium alloy raw materials are melted and flow to the flow channel, until the flow channel is interrupted, all the edge line patterns are turned off, the main pattern of the crucible crystallizer region is retained, the emission current is gradually decreased with time, and the area of the main pattern of the crucible crystallizer region is gradually reduced, the ingot hot top is completed, and after cooling, the furnace is discharged.

[0039] The method for improving the surface quality of titanium or titanium alloy EB ingot provided by the present application adopts multi-layer superimposed design of the electron beam scanning pattern of the crucible crystallizer region, increases the electron beam input energy of the titanium liquid in contact with the water-cooled copper crucible crystallizer, increases the temperature of the titanium liquid in the edge part, reduces the influence of the quenching effect, and promotes the better filling of the titanium liquid; at the same time, the temperature gradient from the center of the ingot to the edge part can be reduced, the temperature uniformity of the cross section of the crystallization region of the ingot can be improved, the relatively gentle solid-liquid phase line can be obtained, and the quality of the ingot can be improved. In addition, the edge line superposition energy can achieve the purpose of improving the influence of the condensate in the upper edge inner wall of the crystallizer on the surface quality of the ingot.

[0040] Specifically, the loading of the titanium or titanium alloy raw materials into the feeder in step (1) and the preheating and smelting of the electron beam cold bed comprise:

[0041] Step (101) loads the titanium or titanium alloy raw materials into the feeder, and after vacuumizing to meet the starting gun conditions, opens the electron gun to preheat the smelting cold bed, the refining cold bed and the overflow cold bed region, and completes the preheating after the shell is fully melted.

[0042] The step (102) melts the titanium or titanium alloy raw material, and the fresh titanium liquid enters the melting pool, gradually fills the melting cold bed, the refining cold bed, the overflow cold bed and the crucible crystallizer, and then enters the normal melting stage.

[0043] Specifically, the step (2) is that the edge line pattern of the four peripheral parts is superimposed on the main pattern in the crucible crystallizer area, including:

[0044] The main pattern covers the crucible crystallizer area, and the scanning pattern with the same width as the main pattern and the length of 5% to 20% (for example, 5%, 10%, 12%, 20%, etc.) of the length of the main pattern is arranged near the end of the ingot near the overflow port, which is coincided with the main pattern and close to the end edge line of the main pattern near the overflow port, to define the near-end edge line pattern; and the scanning pattern with the same width as the main pattern and the length of 5% to 25% (for example, 5%, 8%, 12%, 15%, 25%, etc.) of the length of the main pattern is arranged near the end of the ingot far from the overflow port, which is coincided with the main pattern and close to the end edge line of the main pattern far from the overflow port, to define the far-end edge line pattern.

[0045] More specifically, the step (2) is that the edge line pattern of the four peripheral parts is superimposed on the main pattern in the crucible crystallizer area, further including:

[0046] The scanning pattern with the same width as the main pattern and the length of 5% to 18% (for example, 5%, 8%, 18%, etc.) of the width of the main pattern is arranged near the upper and lower edges (defining the upper and lower angles of the cross-sectional view of the ingot) in the crucible crystallizer area, which is close to the upper and lower edge lines of the main pattern, to define the upper edge line pattern and the lower edge line pattern.

[0047] The present application superimposes the edge line pattern of the four peripheral parts on the main pattern in the crucible crystallizer area, so that the temperature of the titanium liquid in the peripheral part is relatively high, which promotes the filling of the titanium liquid and avoids the chilling effect adjacent to the crystallizer, effectively improving the defects of the ingot caused by surface cold separation and cracking during the ingot drawing process.

[0048] The present application superimposes the edge line pattern, which has relatively high energy than the main pattern, to better remove the condensate accidentally wrapped into the melting pool on the upper edge inner wall of the crystallizer, and avoid the formation of insoluble or inclusions in the ingot.

[0049] Further, the scanning duration of the near-end edge line pattern is 30-80 ms, for example, can be 30 ms, 50 ms, 60 ms, 80 ms, etc.; the scanning duration of the far-end edge line pattern is 20-100 ms, for example, can be 20 ms, 30 ms, 50 ms, 60 ms, 100 ms, etc.; the scanning duration of the upper edge line pattern and the lower edge line pattern is 60-220 ms, for example, can be 60 ms, 80 ms, 110 ms, 220 ms, etc.

[0050] The present application designs suitable pattern range and residence time parameters through the superposition of edge line patterns, reasonably formulates energy distribution, so that the temperature of the melt to be solidified in the crucible is more uniform, the solid-liquid two-phase line is smoother, the solidification process of the outside and the core of the ingot tends to be synchronized, and the internal quality of the ingot is improved.

[0051] Preferably, the emission current in step (3) decreases to 0; and the area of the main pattern of the crucible crystallizer region is reduced to 50%.

[0052] Example 1: 200 1290mm specification pure titanium TA2 flat ingot

[0053] Step 1, the raw material recycling material is loaded into the feeder, and after vacuumizing to meet the starting gun conditions, the electronic gun is opened to preheat the melting bed, the refining bed and the overflow bed area, and the preheating is completed after the solid shell is fully melted.

[0054] Step 2, the raw material is melted, the fresh titanium liquid enters the molten pool, and after gradually filling the melting bed, the refining bed, the overflow bed and the crucible crystallizer, the normal melting stage is entered.

[0055] Step 3, the electronic beam scanning pattern of the crystallization region is set as follows: the main pattern covers the crucible crystallizer region, the near-end edge line pattern has the same width as the main pattern and the length of 12% of the length of the main pattern, and the scanning duration is 60 ms; the far-end edge line pattern has the same width as the main pattern and the length of 15% of the length of the main pattern, and the scanning duration is 60 ms; the upper edge line pattern and the lower edge line pattern are set to have the width of 8% of the width of the main pattern and the same length as the main pattern, and the scanning duration is 110 ms.

[0056] Step 4, after the raw material is melted and flows to the flow channel, the flow channel is cut off, all the edge line patterns are turned off, the main pattern of the crucible crystallizer region is retained, the emission current is decreased to 0 over time, and the main pattern area is reduced to 50%, the hot top of the ingot is completed, and after cooling, the furnace is discharged and the surface quality is inspected.

[0057] The surface quality of the blank of 4 surfaces is inspected, and the surface good product rate is 97% according to the inspection record of the type, number and depth of defects per meter.

[0058] Example 2: 200 1150mm specification pure titanium TA1 slab

[0059] Step 1, the raw material sponge titanium is loaded into the feeder, vacuum is extracted until the starting gun condition is met, then the electron gun is turned on to preheat the melting bed, refining bed and overflow bed area, and the preheating is completed after the shell is fully melted.

[0060] Step 2, the raw material is melted and discharged, the fresh titanium liquid enters the molten pool, and after gradually filling the melting bed, refining bed, overflow bed and crucible crystallizer, it enters the normal melting stage.

[0061] Step 3, the electron beam scanning pattern of the crystallization area is set as follows: the main pattern covers the crucible crystallizer area, the near-end edge pattern has the same width as the main pattern and the length is 10% of the length of the main pattern, the scanning duration is 50 ms; the far-end edge pattern has the same width as the main pattern and the length is 12% of the length of the main pattern, the scanning duration is 50 ms; the upper edge pattern and the lower edge pattern are set to have a width of 5% of the width of the main pattern and the same length as the main pattern, and the scanning duration is 110 ms.

[0062] Step 4, after the raw material is melted and flows to the flow channel, the flow is cut off, all edge patterns are turned off, the main pattern of the crucible crystallizer area is retained, and the emission current is gradually decreased to 0 over time, the main pattern area is reduced to 50%, the ingot hot top is completed, and after cooling, the furnace is discharged and the surface quality is inspected.

[0063] The surface quality of the blank is inspected on 4 surfaces, and the inspection record is recorded according to the type, number and depth of defects per meter, and the surface good product rate is 98%.

[0064] Example 3: 200 1290mm specification TC4 titanium alloy slab

[0065] Step 1, the raw material is loaded into the feeder, vacuum is extracted until the starting gun condition is met, then the electron gun is turned on to preheat the melting bed, refining bed and overflow bed area, and the preheating is completed after the shell is fully melted.

[0066] Step 2, the raw material is melted and discharged, the fresh titanium liquid enters the molten pool, and after gradually filling the melting bed, refining bed, overflow bed and crucible crystallizer, it enters the normal melting stage.

[0067] Step 3, the electron beam scanning pattern of the crystallization area is set as follows: the main pattern covers the crucible crystallizer area, the near-end edge pattern has the same width as the main pattern and the length is 5% of the length of the main pattern, the scanning duration is 30 ms; the far-end edge pattern has the same width as the main pattern and the length is 8% of the length of the main pattern, the scanning duration is 30 ms; the upper edge pattern and the lower edge pattern are set to have a width of 5% of the width of the main pattern and the same length as the main pattern, and the scanning duration is 80 ms.

[0068] Step 4, the raw material flows to the flow channel after melting until the flow channel is interrupted, all the side line patterns are closed, the main pattern of the crucible crystallizer area is reserved, the emission current is gradually decreased to 0 with time, the main pattern area is reduced to 50%, the ingot hot sealing is completed, and the furnace is discharged after cooling, and the surface quality is inspected.

[0069] The blank surface quality of the four surfaces is inspected, and the inspection record is recorded according to the type, number and depth of defects per meter, and the surface good product rate is 94%.

[0070] Comparative Example 1: 200 1290mm specification TA2 pure titanium flat ingot

[0071] Step 1, the raw material is loaded into the feeder, vacuum is extracted until the electron gun is started, the preheating of the melting bed, the refining bed and the overflow bed area is started, and the preheating is completed after the shell is fully melted.

[0072] Step 2, the raw material is melted and discharged, the fresh titanium liquid enters the molten pool, and then gradually fills the melting bed, the refining bed, the overflow bed and the crucible crystallizer, and then enters the normal melting stage.

[0073] Step 3, the electron beam scanning pattern of the crystallization area is only a single main pattern covering the crucible crystallizer area, and there is no side line pattern.

[0074] Step 4, the raw material flows to the flow channel after melting until the flow channel is interrupted, the main pattern of the crucible crystallizer area is gradually decreased to 0 with time, the main pattern area is reduced to 50%, the ingot hot sealing is completed, and the furnace is discharged after cooling, and the surface quality is inspected.

[0075] The blank surface quality of the four surfaces is inspected, and the inspection record is recorded according to the type, number and depth of defects per meter, and the surface good product rate is 92%.

[0076] Figure 3 The surface state of the EB ingot before improvement obtained from Comparative Example 1; Figure 4 The surface state of the EB ingot after improvement obtained from Example 1. Figure 3 It can be seen from the above that the surface of the ingot before improvement has multiple cold shut and inclusion defects, and the possibility of containing subsurface shrinkage holes in the lower layer inside the overflow is very high. Figure 4 It can be seen from the above that the cold shut inclusion defect and the overflow defect are greatly improved by the process method provided by the application.

[0077] It should be noted that in this paper, terms such as "including", "containing" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or includes elements inherent to such process, method, article or equipment.

[0078] While embodiments of the application have been shown and described, it is to be understood that the application is not limited to the details of the embodiments described, since numerous changes, modifications, substitutions and variations can be made thereto without departing from the spirit and scope of the application as defined by the appended claims and their equivalents.

Claims

1. A method for improving the surface quality of titanium or titanium alloy EB ingots, characterized in that, Includes the following steps: (1) Load titanium or titanium alloy raw materials into the feeder and preheat and melt them with an electron beam cooling bed; (2) The electron beam scanning pattern of the crucible crystallizer area is set as follows: On the basis of the main pattern of the crucible crystallizer area, the edge pattern of the four surrounding parts is superimposed to increase the electron beam input energy of the titanium liquid in contact with the crucible crystallizer, so as to increase the temperature of the liquid at the edge. Specifically, this includes: The main graphic covers the crucible crystallizer area. Near the overflow port, a scanning graphic with the same width as the main graphic and a length of 5% to 20% of the main graphic is set at the near end of the pull, overlapping with the main graphic and close to its edge line near the overflow port, defining the near end edge graphic. At the far end of the pull, a scanning graphic with the same width as the main graphic and a length of 5% to 25% of the main graphic is set, overlapping with the main graphic and close to its far end edge line, defining the far end edge graphic. Inside the crucible crystallizer area, scanned graphics with a width of 5% to 18% of the width of the main graphic and a length the same as the main graphic are set on the upper and lower edges, respectively, and the positions are close to the upper and lower edges inside the main graphic, defining the upper edge graphic and the lower edge graphic. The scanning duration of the near edge pattern is 30-80ms; the scanning duration of the far edge pattern is 20-100ms; and the scanning duration of the upper edge pattern and the lower edge pattern is 60-220ms. (3) After the titanium or titanium alloy raw material is melted, it flows to the flow channel until the flow channel is cut off, all edge patterns are closed, the main pattern of the crucible crystallizer area is retained, and the emission current is reduced over time to reduce the area of ​​the main pattern of the crucible crystallizer area, thus completing the hot capping of the ingot, and it is then cooled and taken out of the furnace.

2. The method for improving the surface quality of titanium or titanium alloy EB ingots according to claim 1, characterized in that, Step (1) involves loading titanium or titanium alloy raw materials into a feeder for electron beam cooling bed preheating and melting, including: (101) Load titanium or titanium alloy raw materials into the feeder, evacuate to meet the conditions for starting the gun, and then turn on the electron gun to preheat the melting cold bed, refining cold bed and overflow cold bed area until the solidified shell is fully melted to complete the preheating. (102) The titanium or titanium alloy raw material is fed and melted. Fresh titanium liquid enters the molten pool and gradually fills the melting cold bed, the refining cold bed, the overflow cold bed and the crucible crystallizer before entering the normal smelting stage.

3. The method for improving the surface quality of titanium or titanium alloy EB ingots according to claim 1, characterized in that, The emission current in step (3) is reduced to 0; the area of ​​the main pattern in the crucible crystallizer region is reduced to 50%.

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