Preparation method of high-quality and large-size titanium forgings for cathode roller

Abstract

The present application relates to non-ferrous metal processing technical field, specifically to a kind of preparation method of high-quality, large-specification titanium forge piece for cathode roller, including using VAR furnace 3 times melting out 1040mm, 12 tons of TA1 cast ingot;After casting ingot is planed and milled, brush anti-oxidation coating, after heating, heat preservation, multi-fire forging is made Φ1060×770mm, about 3 tons of TA1 bar blank, bar blank grain size reaches 5~6 level.After bar blank is heated, it is punched, reamed, rolled out Φ2800 / Φ2620×~710mm, 2400kg~2500kg of ring blank, ring blank grain size reaches 6~7.After ring blank is treated at 620~630 ℃, heat preservation 90min, grain size reaches 6~8 level.Furthermore, it is turned to obtain Φ2774 / Φ2661×672~675mm, ~1460kg of spinning ring blank for cathode roller.Using the preparation method of the present application, high-quality, large-specification cathode roller spinning ring blank can be obtained, which can meet the application requirements of titanium forge piece in electrolytic copper foil field.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of non-ferrous metal processing, and particularly relates to a preparation method of high-quality and large-specification titanium forge piece for a cathode roller. BACKGROUND

[0002] Electrolytic copper foil is one of the basic materials for manufacturing electronic products such as copper-clad plate, printed circuit board and lithium ion battery. With the increasing types and demand of copper foil in the market, the development of the main part of the foil machine, the cathode roller, has undergone a series of changes. The diameter specifications of the cathode roller have changed from 500 mm, 1000 mm, 1500 mm, 2000 mm, 2338 mm to 2500 mm. Currently, there are 2700 mm, 3200 mm and even 3600 mm diameter cathode rollers abroad.

[0003] Generally, the titanium forge piece for the cathode roller is prepared from industrial pure titanium TA1. The tensile strength of TA1 pure titanium is about 400 MPa, and it has high plasticity and excellent forming process performance. The long-term working temperature is 300 DEG C, and it can be processed into various semi-finished products such as bars, forgings, pipes and castings, and is widely used in the fields of aviation, aerospace, chemical industry, medical treatment, construction and new energy.

[0004] The internal quality of the cathode roller mainly depends on the size of the grain size. Most of the production enterprises in China are at the level of 7-8, while the grain size of the forge piece blank for preparing the cathode roller is below 5, which cannot meet the high-quality requirement of the grain size of the cathode roller blank being 6 or above, and restricts the engineering application of the cathode roller. In order to solve the above technical problems, the following technical bottlenecks need to be broken through:

[0005] 1. Large-scale ingot preparation technology

[0006] To prepare a cathode roller with a diameter of 2700 mm and above, a titanium ingot with a diameter of 1040 mm and a weight of more than 10 tons needs to be melted. The uniformity of the composition and the content of oxygen and other impurities of the ingot will have a significant impact on the uniformity of the cathode roller forge piece, and further affect whether the mechanical properties meet the standards.

[0007] 2. Large-specification bar blank preparation technology

[0008] Due to the large size of the cathode roller, the size of the ring blank of the forge piece required is large. The diameter and weight of the bar blank required for preparing the ring blank are larger than those of conventional titanium forgings. Since the forging of titanium and titanium alloy has organizational heredity, in order to make the ring blank obtain a small and uniform organization, the forging process parameters of the large-specification bar blank, such as initial forging temperature, deformation speed, deformation amount and final forging temperature, need to be designed and improved to meet the needs of the preparation of the ring blank.

[0009] 3. Ultra-large-specification ring blank preparation technology

[0010] The specification of the titanium ring blank required for the Ф2700 mm cathode roller is Ф2774 / Ф2661* L mm, which is an ultra-large diameter ring rolled piece. In order to ensure that the ultra-large specification ring blank has a fine and uniform structure and performance that meets the technical requirements, the rolling temperature, radial rolling deformation, axial rolling deformation, deformation speed and the like need to be designed and improved. SUMMARY

[0011] In view of the above technical bottleneck, the present application innovatively designs and optimizes the ingot melting process, bar blank forging process and ring blank preparation process, and controls the key process parameters such as forging / rolling temperature, deformation distribution in fire times, forging / rolling deformation speed, to prepare a bar blank and a ring blank with uniform composition and fine grain size, and finally obtain a high-quality, large-specification titanium forging for a cathode roller that meets the design requirements in grain size.

[0012] Specifically, the present application provides a preparation method of a high-quality, large-specification titanium forging for a cathode roller, comprising the following steps:

[0013] Step 1, bar blank forging:

[0014] The pretreated TA1 ingot is placed in a natural gas furnace and heated to 1050-1200℃, and after holding for 360-480min, it is taken out of the furnace for single-phase zone forging breakdown, and the deformation is controlled at 60%-80%;

[0015] The bar blank obtained by the breakdown forging is placed in a resistance furnace and heated to 800-850℃, and after holding for 240-360min, it is taken out of the furnace for α+β two-phase zone upsetting and drawing forging, and the deformation is controlled at 55-75%, and the final forging temperature is not lower than 700℃, to obtain a bar blank with a grain size of 5-6 levels;

[0016] Step 2, ring blank preparation:

[0017] The bar blank prepared in step 1 is placed in a resistance furnace and heated to 780-850℃, and after holding for 120-240min, it is taken out of the furnace for punching, and the punching final forging temperature is not lower than 700℃;

[0018] The blank after punching is placed in a resistance furnace and heated to 750-850℃, and after holding for 120-240min, it is taken out of the furnace for hole expansion, to reach the preset specification, and the hole expansion final forging temperature is not lower than 650℃;

[0019] The resistance furnace is heated to 700℃, and the blank after hole expansion is placed in it, heated to 720℃ and held for 120min, then continuously heated to 820-860℃ and held for 60-150min, and taken out of the furnace, and rolled on a ring rolling machine, and the final rolling temperature is not lower than 700℃, to obtain a ring blank with a grain size of 6-7 levels;

[0020] Step 3, heat treatment:

[0021] The ring blank prepared in step 2 is placed in a resistance furnace with a temperature control accuracy of ±5℃, heated to 600-650℃ and kept for 60-120min, and then taken out of the furnace for air cooling, to obtain a high-quality, large-size TA1 ring blank for cathode roller with a grain size of 6-8.

[0022] As a further illustration of the present application, the preparation process of the TA1 ingot comprises: controlling the melting current to be 30-40kA, the melting voltage to be 27-39V, and melting for 3 times to obtain a TA1 ingot with a diameter of 1040mm and a weight of 10 tons on a vacuum consumable arc furnace.

[0023] As a further illustration of the present application, the melting process parameters are: the melting current is 32-38kA, the melting voltage is 29-37V, the vacuum degree of the melting chamber is ≤5, and the air leakage rate is ≤0.7Pa / min.

[0024] As a further illustration of the present application, the chemical composition of the TA1 ingot is: Ti: balance, Fe≤0.05, C≤0.03, N≤0.03, O≤0.06, and H≤0.002.

[0025] As a further illustration of the present application, the bar blank is uniformly coated with an anti-oxidation coating before the bar blank forging and the ring blank preparation.

[0026] As a further illustration of the present application, the specification of the bar blank obtained after the bar blank forging is Φ1060 +5 ×~770mm, and the single weight is ~3 tons.

[0027] As a further illustration of the present application, in step 2, the hammer head and the punch are fully preheated before punching, and the preheating temperature is 150-300℃; punching is performed on a forging press, and the size of the core rod obtained after punching is ≤Φ350×250mm.

[0028] As a further illustration of the present application, in step 2, the hammer head and the punch are fully preheated before punching, and the preheating temperature is 150-300℃; punching is performed on a forging press, and the size of the core rod obtained after punching is ≤Φ350×250mm.

[0029] As a further illustration of the present application, the specification of the ring blank obtained after the hole expansion and rolling is Φ2800 / Φ2620×~710mm, and the single weight is ~2500kg.

[0030] As a further illustration of the present application, the method further comprises: step 4, machining:

[0031] The forged piece obtained by the heat treatment of step 4 is subjected to rough machining and finish machining on a vertical lathe, and finally a Φ2774+2 / Φ2661-2*670 +5 The spinning ring blank for the cathode roller has an inner and outer surface roughness Ra value of no more than 3.2 μm.

[0032] Compared with the prior art, the present application has the following beneficial technical effects:

[0033] The present application finally obtains TA1 titanium forgings with a grain size of 6 or above by innovative design and control of the smelting process parameters, forging process parameters and rolling process parameters, thereby meeting the demand for high-quality and large-specification blanks for cathode rollers. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 A grain size photograph (7 levels) of the high-quality and large-specification TA1 ring blank forgings for cathode rollers prepared in the embodiments of the present application. DETAILED DESCRIPTION

[0035] 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 a 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.

[0036] The present application provides a preparation method of high-quality and large-specification titanium forgings for cathode rollers, comprising the following steps:

[0037] Step 1, ingot preparation:

[0038] In a vacuum consumable arc furnace (VAR), a TA1 ingot with a diameter of 1040 mm and a weight of 10 tons is smelted by controlling the smelting current to be 30-40 kA, the smelting voltage to be 27-39 V and the smelting to be 3 times. After the ingot is planed and milled, it is uniformly brushed with an anti-oxidation coating for standby use.

[0039] Further preferred smelting process parameters are: smelting current 32-38 kA, for example, 32 kA, 34 kA, 36 kA, 38 kA, etc.; smelting voltage 29-37 V, for example, 29 V, 31 V, 33 V, 35 V, 37 V, etc.; smelting chamber vacuum degree ≤5, air leakage rate ≤0.7 Pa / min. The chemical composition of the TA1 ingot is: Ti: balance, Fe ≤0.05, C ≤0.03, N ≤0.03, O ≤0.06, H ≤0.002.

[0040] The above-mentioned smelted blank selects 0 grade or above 0 grade small particle sponge titanium, and a TA1 electrode is pressed on an 8000-ton oil press.

[0041] Step 2, bar forging:

[0042] The step 1 casting ingot coated with the anti-oxidation coating TA1 is placed in a natural gas furnace and heated to 1050-1200℃, and held for 360-480 min before being taken out of the furnace, and then subjected to single-phase zone forging breakdown, so as to sufficiently break the coarse as-cast structure and control the deformation amount to be 60%-80%.

[0043] Preferably, the single-phase zone heating temperature is 1050-1100℃, for example, 1050℃, 1080℃, 1100℃, etc.; the holding time is for example 360 min, 380 min, 400 min, 420 min, 440 min, 460 min, 480 min, etc.; and the deformation amount is for example 60%, 65%, 70%, 75%, 80%.

[0044] The bar blank obtained by the breakdown forging is placed in a resistance furnace and heated to 800-850℃, and held for 240-360 min before being taken out of the furnace, and then subjected to α+β two-phase zone upsetting and drawing forging, with the finish forging temperature being not lower than 700℃, and the deformation amount being controlled to be 55-75%, so as to further break the as-cast structure, refine the grains, and obtain a bar blank with a grain size of 5-6 levels, a specification of Φ1060 +5 ×~770 mm, and a single weight of 3 tons.

[0045] Due to the large deformation resistance of large titanium forgings, if the finish forging temperature is too low, the blank may crack. After a large number of experiments, a finish forging temperature of not lower than 700℃ is finally selected.

[0046] Preferably, the resistance furnace heating temperature is 820-850℃, for example, 820℃, 835℃, 850℃, etc.; the holding time is for example 240 min, 260 min, 280 min, 300 min, 320 min, 360 min, etc.; and the deformation amount is for example 55%, 60%, 65%, 70%, 75%, etc.

[0047] Step 3, ring blank preparation:

[0048] The bar blank prepared in step 2 is coated with an anti-oxidation coating, and then placed in a resistance furnace and heated to 780-850℃, and held for 120-240 min before being taken out of the furnace, and then punched on a forging press.

[0049] Preferably, the resistance furnace heating temperature is for example 780℃, 800℃, 820℃, 850℃, etc.; and the holding time is for example 120 min, 150 min, 180 min, 210 min, 240 min, etc.

[0050] Wherein, the punch core rod size is ≤Φ350*250mm, and the punch finish forging temperature is not lower than 700℃. Before punching, the hammer head, punch and the like are fully preheated, and the preheating temperature is 150-300℃, so as to ensure the forging quality and prevent cracks; the preheating temperature may be, for example, 150℃, 180℃, 210℃, 240℃, 270℃, 300℃ and the like.

[0051] After the punched blank is placed in the resistance furnace and heated to 750-850℃, the blank is kept for 120-240min and then taken out, and the hole expansion is carried out on the forging press to reach the preset specification, and the hole expansion finish forging temperature is not lower than 650℃; the heating temperature of the punched blank may be, for example, 750℃, 775℃, 800℃, 825℃, 850℃ and the like; and the holding time may be, for example, 120min, 150min, 180min, 210min, 240min and the like.

[0052] Before the hole expansion, the drop hammer, core rod and the like are fully preheated, and the preheating temperature is 150-300℃. The blank size after the hole expansion is Φ1405 / Φ1030(+0.15, -0.15)*760(+5, -5)mm. The preheating temperature may be, for example, 150℃, 180℃, 210℃, 240℃, 270℃, 300℃ and the like.

[0053] After the hole expansion, the resistance furnace is heated to 700℃, and then the blank after the hole expansion is put in, heated to 720℃ and kept for 120min, and then heated to 820-860℃ and kept for 60-150min to take out, and then the rolling is carried out on the rolling ring machine, and the final rolling temperature is not lower than 700℃, so as to further break the crystal grains, and obtain the ring blank with a grain size of 6-7 levels, a specification of Φ2800 / Φ2620*~710mm and a single weight of ~2500kg.

[0054] Preferably, the heating temperature of the blank after the hole expansion in the resistance furnace is 820-840℃, for example, 820℃, 830℃, 840℃ and the like; and the holding time is 90-150min, for example, 90min, 110min, 130min, 150min and the like.

[0055] Step 4, heat treatment:

[0056] The ring blank prepared in step 3 is placed in the resistance furnace with a temperature control precision of ±5℃, heated to 600-650℃ and kept for 60-120min, and then taken out and air cooled, so as to obtain the high-quality, large-specification TA1 ring blank forging for cathode roller with a grain size of 6-8 levels.

[0057] Preferably, the heating temperature of the heat treatment is 620-630℃, for example, it can be 620℃, 625℃, 630℃, etc.; the holding time is preferably 90-120min, for example, it can be 90min, 100min, 110min, 120min, etc.

[0058] In the heat treatment, the temperature of the heat treatment needs to be selected appropriately for the large ring blank, that is, at 620-630℃, to ensure appropriate grain growth, and large grains cannot occur, and the holding time is controlled at 90-120min, which can fully eliminate the internal stress of the large ring blank and ensure complete dynamic recovery.

[0059] Step 5, machining: the blank obtained in step 4 is subjected to rough machining and finish machining on a vertical lathe, and finally a Φ2774 +2 / Φ2661 -2 ×670 +5 mm, weight ~1500kg cathode roller spinning ring blank, the inner and outer surface roughness Ra value of the ring blank is not more than 3.2μm.

[0060] The following will be described in conjunction with specific examples: Example 1

[0061] Step 1, ingot preparation: in the VAR furnace, control the melting current at 32kA, the melting voltage at 27V, and melt 3 times to obtain a TA1 ingot 1 with a diameter of 1040mm and a weight of 10 tons. After planing and milling, the ingot is evenly brushed with anti-oxidation paint.

[0062] Step 2, bar blank preparation: the ingot brushed with anti-oxidation paint in step 1 is placed in a natural gas furnace and heated to 1050℃, and held for 480min before being taken out of the furnace. Single-phase zone upsetting and piercing forging is performed to break the coarse as-cast structure and the deformation amount is controlled at 60%.

[0063] Then it is placed in a resistance furnace and heated to 800℃, and held for 360min before being taken out of the furnace. (α+β) two-phase zone upsetting and piercing forging is performed to further break the as-cast structure, and a bar blank 1 with a grain size of 5 levels, a specification of Φ1062×772mm, and a single weight of ~3076kg is obtained.

[0064] Step 3, ring blank preparation: the rod blank prepared in step 2 is coated with an anti-oxidation coating, then placed in a resistance furnace and heated to 780℃ for 240 minutes, then taken out of the furnace, and punched on a forging press. The size of the punched core rod is ≤Φ350×250mm, and the final forging temperature is not lower than 700℃. Before punching, the hammer head, punch and the like should be preheated sufficiently, and the preheating temperature is 150℃, so as to ensure the forging quality and prevent cracks. Then the blank is placed in a resistance furnace and heated to 750℃ for 240 minutes, then taken out of the furnace, and expanded on a forging press. The final forging temperature of the expanded hole is not lower than 650℃. Before expanding, the anvil, core rod and the like are preheated sufficiently, and the preheating temperature is 150℃. After expanding, the size of the blank is Φ1405 / Φ1030(+0.15, -0.15)×760(+5, -5)mm. After expanding, the resistance furnace is heated to 700℃, and then the blank is placed in the furnace. The temperature is raised to 720℃ and kept for 120 minutes, then raised to 820℃ and kept for 150 minutes, and then taken out of the furnace. Rolling is performed on a ring rolling machine, and the final rolling temperature is not lower than 700℃, so as to further break the grains. A ring blank 1 with a grain size of 6, a specification of Φ2800 / Φ2620×713mm and a single weight of ~2458kg is obtained.

[0065] Step 4, heat treatment: the blank prepared in step 3 is placed in a resistance furnace with a temperature control accuracy of ±5℃, heated to 650℃ and kept for 60 minutes, then taken out of the furnace and air cooled, so as to obtain a high-quality, large-specification TA1 ring blank for cathode roller with a grain size of 6.

[0066] Step 5, machining: the blank obtained in step 4 is subjected to rough machining and finish machining on a vertical lathe, so as to finally obtain a spinning ring blank for cathode roller with a specification of Φ2774 / Φ2661×672mm and a weight of about 1458kg.

[0067] Example 2

[0068] Step 1, ingot preparation: a TA1 ingot with a diameter of 1040mm and a weight of 10 tons is prepared on a VAR furnace by controlling the melting current to be 31-39kA, the melting voltage to be 33V and the melting to be 3 times.

[0069] Step 2, rod blank preparation: the ingot coated with the anti-oxidation coating in step 1 is placed in a natural gas furnace and heated to 1100℃ for 420 minutes, then taken out of the furnace, and subjected to single-phase zone upsetting and drawing to break the coarse as-cast structure and control the deformation to be 70%. Then the ingot is placed in a resistance furnace and heated to 825℃ for 300 minutes, then taken out of the furnace, and subjected to (α+β) two-phase zone upsetting and drawing to further break the as-cast structure. A rod blank 1 with a grain size of 5.5, a specification of Φ1061×773mm and a single weight of ~3074kg is obtained.

[0070] Step 3, ring blank preparation: the rod blank prepared in step 2 is coated with an anti-oxidation coating, then placed in a resistance furnace and heated to 815℃ for 180 minutes, then taken out of the furnace, and punched on a forging press. The size of the punched core rod is ≤Φ350×250mm, and the final forging temperature is not lower than 700℃. Before punching, the hammer head, punch and the like should be fully preheated to a temperature of 225℃ to ensure the quality of forging and prevent cracks. Then the blank is placed in a resistance furnace and heated to 800℃ for 180 minutes, then taken out of the furnace, and expanded on a forging press. The final forging temperature of the expanded hole is not lower than 650℃. Before expanding, the anvil, core rod and the like are fully preheated to a temperature of 225℃. After expanding, the size of the blank is Φ1405 / Φ1030(+0.15, -0.15)×760(+5, -5)mm. After expanding, the resistance furnace is heated to 700℃, and then the blank is placed in the furnace. The temperature is raised to 720℃ and kept for 120 minutes, then raised to 830℃ and kept for 105 minutes, then taken out of the furnace, and rolled on a ring rolling machine. The final rolling temperature is not lower than 700℃, further breaking the grains, obtaining a ring blank 1 piece with a grain size of 6.5, a specification of Φ2800 / Φ2620×712mm, and a single weight of ~2454kg.

[0071] Step 4, heat treatment: the ring blank prepared in step 3 is placed in a resistance furnace with a temperature control accuracy of ±5℃, heated to 640℃ and kept for 90 minutes, then taken out of the furnace and air cooled, obtaining a high-quality, large-specification TA1 ring blank for cathode roller with a grain size of 6.5.

[0072] Step 5, machining: the blank obtained in step 4 is rough machined and finish machined on a vertical lathe, finally obtaining a spinning ring blank for cathode roller with a specification of Φ2774 / Φ2661×674mm and a weight of about 1463kg. Example 3

[0073] Step 1, ingot preparation: a TA1 ingot with a diameter of 1040mm and a weight of 10 tons is melted on a VAR furnace with a melting current of 38kA, a melting voltage of 29V and 3 times of melting. The ingot is evenly coated with an anti-oxidation coating after planing and milling.

[0074] Step 2, rod blank preparation: the ingot coated with the anti-oxidation coating in step 1 is placed in a natural gas furnace and heated to 1100℃ for 360 minutes, then taken out of the furnace, and subjected to single-phase zone upsetting and drawing to break the coarse as-cast structure and control the deformation to 80%. Then it is placed in a resistance furnace and heated to 850℃ for 240 minutes, then taken out of the furnace, and subjected to (α+β) two-phase zone upsetting and drawing to further break the as-cast structure, obtaining a rod blank 1 piece with a grain size of 5.5, a specification of Φ1063×771mm and a single weight of ~3078kg.

[0075] Step 3, ring blank preparation: the rod blank prepared in step 2 is coated with an oxidation-resistant coating, then placed in a resistance furnace and heated to 850℃ for 120 minutes, and then taken out of the furnace. Punching is performed on a forging press. The size of the punched core rod is ≤Φ350*250mm, and the final forging temperature is not lower than 700℃. Before punching, the hammer head, punch and the like should be preheated sufficiently, and the preheating temperature is 300℃, so as to ensure the forging quality and prevent cracks. Then the blank is placed in a resistance furnace and heated to 850℃ for 120 minutes, and then taken out of the furnace. Hole expansion is performed on a forging press, and the hole expansion final forging temperature is not lower than 650℃. Before hole expansion, the anvil, core rod and the like are preheated sufficiently, and the preheating temperature is 300℃. After hole expansion, the blank size is Φ1405 / Φ1030(+0.15, -0.15)*760(+5, -5)mm. After hole expansion, the resistance furnace is heated to 700℃, and then the blank is placed in the resistance furnace. The temperature is raised to 720℃ and kept for 120 minutes, and then the temperature is continuously raised to 840℃ and kept for 60 minutes. The blank is taken out of the furnace, and rolling is performed on a ring rolling machine. The final rolling temperature is not lower than 700℃, the grain size is 6.5, the specification is Φ2800 / Φ2620*714mm, and the single weight of the ring blank 1 is ~2461kg.

[0076] Step 4, heat treatment: the ring blank prepared in step 3 is placed in a resistance furnace with a temperature control accuracy of ±5℃, heated to 620℃ and kept for 120 minutes, and then taken out of the furnace and air-cooled to obtain a high-quality, large-specification TA1 ring blank for a cathode roller with a grain size of 7.

[0077] Step 5, machining: the blank obtained in step 4 is subjected to rough machining and finish machining on a vertical lathe to obtain a spinning ring blank for a cathode roller with a specification of Φ2774 / Φ2661*673mm and a weight of about 1460kg.

[0078] Table 1 is the chemical composition of the TA1 ingot prepared in the example. As can be seen from the data in the table, the chemical composition of the ingot meets the standard requirements of GB / T 3620.1-2016.

[0079] Table 1 Chemical composition of TA1 ingot

[0080]

[0081] Table 2 is the grain size evaluation result of the ring blank prepared in the example. As can be seen from the data in the table, the grain size of the TA1 ring blank prepared by the preparation method of the application meets the technical requirements of 6 or more levels, which shows that the high-quality, large-specification TA1 ring blank for a cathode roller can be obtained by using the method.

[0082] Table 2 Grain size evaluation result

[0083]

[0084] It has to be noted that, as used herein, such terms as "including", "contains" or any other variations thereof are intended to cover a non-exclusive inclusion, such that processes, methods, articles, or apparatuses that comprise a list of elements are not required to comprise only those elements recited, but can also include other elements not expressly listed or inherent to such processes, methods, articles, or apparatuses.

[0085] 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 modifications and changes can be made to the embodiments without departing from the spirit and scope of the application as defined by the appended claims and their equivalents.

Claims

1. A method for preparing high-quality, large-size titanium forgings for cathode rollers, characterized in that, Includes the following steps: Step 1, Billet Forging: The pretreated TA1 ingot is heated to 1100℃ in a natural gas furnace and held for 360 minutes before being removed from the furnace. It is then subjected to single-phase forging to form a billet, with the deformation controlled at 80%. The preparation process of the TA1 ingot includes: controlling the melting current at 30~40kA and the melting voltage at 27~39V in a vacuum consumable arc furnace, and melting three times to produce a TA1 ingot with a diameter of 1040mm and a weight of 10 tons. The billet obtained by the initial forging is placed in a resistance furnace and heated to 850℃. After holding at that temperature for 240 minutes, it is taken out of the furnace and subjected to α+β two-phase region upsetting forging. The deformation is controlled at 75%, and the final forging temperature is not lower than 700℃ to obtain a billet with a grain size of 5.

5. Step 2, Ring preform preparation: The billet prepared in step 1 is placed in a resistance furnace and heated to 850°C. After holding at that temperature for 120 minutes, it is taken out of the furnace and punched. The final forging temperature after punching is not lower than 700°C. After punching, the billet is placed in an electric resistance furnace and heated to 850℃. After holding for 120 minutes, it is taken out of the furnace and expanded to reach the preset specifications. The final forging temperature after expanding the hole is not lower than 650℃. After heating the resistance furnace to 700℃, the expanded billet is placed in, heated to 720℃ and held for 120 minutes, then heated to 840℃ and held for 60 minutes before being taken out of the furnace and rolled on a ring rolling mill with a final rolling temperature of not less than 700℃ to obtain a ring billet with a grain size of 6.

5. Step 3, heat treatment: The ring billet prepared in step 2 is placed in a resistance furnace with a temperature control accuracy of ±5℃, heated to 620℃ and held for 120 minutes before being removed from the furnace and air-cooled to obtain a high-quality, large-size TA1 ring billet forging with a grain size of grade 7 for cathode rolls.

2. The method for preparing high-quality, large-size titanium forgings for cathode rollers as described in claim 1, characterized in that, The smelting process parameters are: smelting current 32-38kA, smelting voltage 29-37V, smelting chamber vacuum degree ≤5, and leakage rate ≤0.7Pa / min.

3. The method for preparing high-quality, large-size titanium forgings for cathode rollers as described in claim 1, characterized in that, The chemical composition of the TA1 ingot is as follows: Ti: balance, Fe≤0.05, C≤0.03, N≤0.03, O≤0.06, H≤0.

002.

4. The method for preparing high-quality, large-size titanium forgings for cathode rollers as described in claim 1, characterized in that, Before the forging of the bar billet and the preparation of the ring billet, the billet needs to be evenly coated with an anti-oxidation coating before being placed in a heating furnace for heating.

5. The method for preparing high-quality, large-size titanium forgings for cathode rollers as described in claim 1, characterized in that, The bar blank obtained after the forging process has a specification of Φ. ×~770mm, single weight is ~3 tons.

6. The method for preparing high-quality, large-size titanium forgings for cathode rollers as described in claim 1, characterized in that, In step 2, before punching, the hammer and punch are fully preheated to a temperature of 150~300℃; punching is performed on the forging press, and the size of the mandrel obtained by punching is ≤Φ350×250mm.

7. The method for preparing high-quality, large-size titanium forgings for cathode rollers as described in claim 1, characterized in that, In step 2, before reaming, the forging press and mandrel are fully preheated to a temperature of 150~300℃; the reaming is then performed on the forging press, and the blank size after reaming is Φ1405 / Φ × mm.

8. The method for preparing high-quality, large-size titanium forgings for cathode rollers as described in claim 1, characterized in that, The ring blank obtained after expansion and rolling has a specification of Φ2800 / Φ2620×~710mm and a single weight of ~2500kg.

9. The method for preparing high-quality, large-size titanium forgings for cathode rollers as described in claim 1, characterized in that, The method further includes: Step 4, machining: The forgings obtained from the heat treatment in step 4 are roughed and finished on a vertical lathe to finally obtain Φ / Φ × A spinning ring blank for cathode rollers with a diameter of mm and a weight of ~1500kg, wherein the surface roughness Ra value of the inner and outer surfaces of the ring blank is not greater than 3.2μm.

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