Preparation process of 10t large single weight wide nickel coil

Abstract

Provided is a preparation process for 10T large single weight wide nickel coil, based on a vacuum consumable arc furnace, a secondary melting method is used for melting the prepared large single weight nickel electrode, and the technical parameters during melting are optimized and improved, solving the problems of large single weight nickel coil preparation difficulty, easy to produce pores, inclusions and deep shrinkage holes under the traditional preparation process, the preparation process is simple, the cost is low, the quality and yield of the nickel ingot after melting are improved, so that the quality of the nickel coil is guaranteed, and the preparation of large single weight high quality wide nickel coil products is especially suitable.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of nickel coil preparation, and particularly relates to a preparation process of 10T-level large single-weight wide-width nickel coil. BACKGROUND

[0002] At present, the traditional vacuum induction melting + electroslag remelting nickel smelting method cannot produce large single-weight ingots, and the maximum is not more than 5T, mainly due to the limitation of the electroslag remelting furnace equipment, which cannot prepare large single-weight wide-width nickel coil; the vacuum consumable arc furnace is generally used for smelting titanium and titanium alloy ingots, and is used for smelting nickel ingots, which is easy to produce internal pores in the upper part of the nickel ingot and deep shrinkage holes in the upper center part. Therefore, based on the vacuum consumable arc furnace, the smelting process needs to be improved to meet the preparation requirements of the large single-weight nickel coil. SUMMARY

[0003] The technical problem solved by the present application is to provide a preparation process of 10T-level large single-weight wide-width nickel coil, which adopts a secondary smelting method to smelt the prepared large single-weight nickel electrode based on the vacuum consumable arc smelting furnace, and optimizes and improves the technical parameters during smelting, thereby solving the problems of large single-weight nickel coil preparation difficulty, easy to produce pores, inclusions and deep shrinkage holes under the traditional preparation process. The preparation process is simple, the cost is low, the quality and yield of the smelted nickel ingot are improved, so that the quality of the nickel coil is guaranteed, and it is especially suitable for the preparation of large single-weight high-quality wide-width nickel coil products.

[0004] The technical solution adopted by the present application is a preparation process of 10T-level large single-weight wide-width nickel coil, comprising the following steps:

[0005] 1) Raw material: 12.5 tons of electrolytic nickel plate with a purity of not less than 99.96% is used, and a shear is used to cut the nickel plate into nickel strips with a width of 200-700mm;

[0006] 2) Consumable electrode preparation: two consumable electrodes are prepared from the cut electrolytic nickel strips, i.e. one 7.7-ton circular electrode with a size of φ700*5000mm and one 4.8-ton circular electrode with a size of φ700*3100mm;

[0007] 3) Smelting: vacuum consumable arc smelting is used to smelt the two circular electrodes twice, wherein a φ760mm copper crystallizer is used for the first smelting, and a φ840mm copper crystallizer is used for the second smelting;

[0008] 4) First skinning and grinding: the nickel ingot obtained by smelting is placed on a lathe for multi-pass lathe skinning, and the feed amount is 1-3mm each time. After the whole nickel ingot is skinned, the local surface defect is turned or ground by a grinding wheel for removal. The treated part should be smooth without steps and corners. The depth-width ratio of the defect position on the upper surface of the nickel ingot is not greater than 1:6, the treatment depth is not greater than 10mm, and the head and bottom of the nickel ingot are chamfered to 40*50-70mm;

[0009] 5) Sampling and chemical composition detection: Chip and block samples are taken from the outer circumferential wall within the range of 230-280 mm from the head and bottom of the nickel ingot, the samples shall not be oxidized, the amount of each chip sample shall not be less than 25 g, the length of the block sample shall be 100 mm and the diameter shall be φ3-φ5, and the analysis of residual elements shall meet the standard of GB / T5235-2021;

[0010] 6) Riser cutting: The riser of the nickel ingot is cut by a sawing bed after ultrasonic flaw detection positioning;

[0011] 7) Forging: The nickel ingot is forged by free forging, the heating temperature of the nickel ingot is 1100℃, the forging size is δ160mm×1260mm×L, and a thick slab is formed;

[0012] 8) Second skinning and grinding: The thick slab is skinned by a multi-pass milling machine, the feed amount of each pass is 1-3 mm, the thick slab should be chamfered along the length of the four edges, the chamfer is (5-20) mm×45°, the Ra value of the surface roughness of the thick slab should be not more than 3.2μm, the local defects on the surface of the thick slab are removed by grinding after overall skinning, the pit depth after cleaning should be not more than 5mm, the cleaning width and cleaning length should be not less than 10 times of the pit depth, and the pit edge generated by grinding is required to be smoothly transitioned with the plate surface;

[0013] 9) Hot rolling: The heating temperature of the thick slab during hot rolling is 1050℃-1150℃, and the size after hot rolling is δ5.0mm×1300mm×L, and a thick nickel coil is formed;

[0014] 10) Stress relief annealing: The thick nickel coil after hot rolling is continuously annealed at 750℃-850℃;

[0015] 11) Surface treatment: The oxide layer on the surface of the thick nickel coil is removed by pickling;

[0016] 12) Cold rolling: The thick nickel coil after surface treatment is cold rolled by a 20-roll cold rolling mill, the size after cold rolling is δ1.0mm×1300mm×L or δ1.5mm×1300mm×L, and a thin nickel coil is formed;

[0017] 13) Annealing: The thin nickel coil after cold rolling is continuously annealed at 750℃-850℃ under argon protection;

[0018] 14) Surface treatment: The thin nickel coil after annealing is pickled to make the surface bright;

[0019] 15) Sampling and performance detection: The head and tail of the thin nickel coil after surface treatment are cut and sampled, and the transverse and longitudinal mechanical properties are detected.

[0020] In the step 2), the preparation step of the consumable electrode is specifically as follows:

[0021] 2-1) The cut electrolytic nickel strip is laid on the shaping frame layer by layer, and each layer is connected by argon arc welding in the length direction, wherein the current during the argon arc welding is 180-260 A, the argon flow rate is 10-15 L / min, and the weld length is 10 mm;

[0022] 2-2) The hinge is tightened, and the baling is performed by using the baling strip with a width of 50 mm and a thickness of 3.0 mm, the baling strip interval is 400 mm, and the baling strip is a pure nickel strip.

[0023] Further, the shaping frame comprises a base frame, a plurality of arc-shaped frames are uniformly distributed along the length direction of the base frame, the opening of the arc-shaped frame is upwardly arranged, and the lower end of the arc-shaped frame is fixed on the base frame. The cut electrolytic nickel strip is laid on the arc-shaped support surface of the arc-shaped frame in the laying order from small to large and then to small, and then welding shaping is performed.

[0024] Further, the base frame adopts two parallel arranged side stand plates and a longitudinal rod arranged between the two side stand plates, a plurality of horizontal rods are uniformly distributed above the side stand plates and the longitudinal rod, and the plurality of horizontal rods fixedly connected with the side stand plates and the longitudinal rod fixedly connect the two side stand plates and the longitudinal rod as a whole.

[0025] Further, the arc-shaped frame comprises two parallel arranged stand columns and an arc-shaped plate with an upward opening and fixedly connected with the side wall of the corresponding side stand column, the lower end of the two stand columns is fixed on the outer wall of the corresponding side stand plate, the lower end of the arc-shaped plate is fixedly connected with the side stand plate and the longitudinal rod, and the inner side wall of the stand column is fixed with a support rod with the lower end fixedly connected with the side wall of the longitudinal rod.

[0026] In the step 3), in the first time of smelting, a φ700*5000 mm round electrode is loaded into a φ760 mm copper crystallizer, the φ700*5000 mm round electrode is welded and fixed at the lower end of the auxiliary electrode, the furnace is opened after the welding position is cooled and solidified, the φ700*5000 mm round electrode is completely smelted, the furnace cover is opened after cooling for about two hours, a φ700*3100 mm round electrode is loaded into the φ760 mm copper crystallizer, and the φ700*3100 mm round electrode is welded and fixed at the lower end of the auxiliary electrode. The furnace is opened after the welding position is cooled and solidified, the φ700*3100 mm round electrode is completely smelted, the furnace is opened after being cooled for at least 7 hours, and the first time of smelting of the two round electrodes is completed;

[0027] After the nickel ingot obtained after the first time of smelting is turned into a flat head, the nickel ingot is loaded into a φ840 mm copper crystallizer, the nickel ingot is welded and fixed at the lower end of the auxiliary electrode, the furnace is opened after the welding position is cooled and solidified, and the nickel ingot is completely smelted. The furnace is opened after being cooled for not less than 10 hours, and the second time of smelting is completed.

[0028] Further, the vacuum degree in the vacuum self-consumption arc melting furnace before the auxiliary electrode is welded with the two circular electrodes with a diameter of 700*5000mm and 700*3100mm is less than or equal to 1Pa, the welding current when the auxiliary electrode is welded with the two circular electrodes is 3-12kA, the welding voltage is 20-40V, and the cooling time after welding is greater than or equal to 30min.

[0029] Further, the vacuum degree in the vacuum self-consumption arc melting furnace before the auxiliary electrode is welded with the two circular electrodes with a diameter of 700*5000mm and 700*3100mm is less than or equal to 1Pa, the welding current when the auxiliary electrode is welded with the two circular electrodes is 3-12kA, the welding voltage is 20-40V, and the cooling time after welding is greater than or equal to 30min.

[0030] Further, the vacuum degree in the vacuum self-consumption arc melting furnace before the auxiliary electrode is welded with the two circular electrodes with a diameter of 700*5000mm and 700*3100mm is less than or equal to 1Pa, the welding current when the auxiliary electrode is welded with the two circular electrodes is 3-12kA, the welding voltage is 20-40V, and the cooling time after welding is greater than or equal to 30min.

[0031] Further, the vacuum degree in the vacuum self-consumption arc melting furnace before the auxiliary electrode is welded with the two circular electrodes with a diameter of 700*5000mm and 700*3100mm is less than or equal to 1Pa, the welding current when the auxiliary electrode is welded with the two circular electrodes is 3-12kA, the welding voltage is 20-40V, and the cooling time after welding is greater than or equal to 30min.

[0032] The advantages of the present application compared with the prior art are:

[0033] 1. The technical scheme is based on the vacuum self-consumption arc melting furnace for preparing a large single heavy nickel electrode, and the two-melting method is used for melting, and the technical parameters are optimized and improved, so that the problems of large single heavy nickel coil preparation difficulty, air hole, inclusion and deep shrinkage hole under the traditional preparation process are solved, and the quality and yield of the nickel ingot after melting are improved.

[0034] 2. When the electrolytic nickel strip prepared by the technical scheme is used as a consumable electrode, it is supported by the arc-shaped surface of the arc-shaped frame under the support of the bottom frame and the plurality of arc-shaped frames distributed along the length direction of the bottom frame, the modeling quality is improved, and the support and shaping conditions are provided for the rapid modeling of the required outer contour shape of the consumable electrode.

[0035] 3. In the melting of the two circular electrodes in the vacuum self-consumption arc melting furnace, the melting parameters are optimized, technical support is provided for the improvement of the quality of the nickel ingot, and conditions are provided for the preparation of the large single heavy nickel coil.

[0036] 4、The preparation process is simple, the cost is low, the quality of the nickel coil is ensured, and the preparation of large single-weight high-quality wide nickel coil products is particularly suitable. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 The figure is a schematic diagram of the shaping frame structure of the present application. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present application will be clearly and completely described below. Figure 1 It should be noted that 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 labor fall within the scope of protection of the present application.

[0039] It should be noted that in this document, the terms "comprise", "contain" or any other variant 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 inherent to such process, method, article or equipment. Without more limitations. The element defined by the sentence "includes a..." does not exclude the presence of another identical element in the process, method, article or equipment including the element.

[0040] 10T large single-weight wide nickel coil preparation process, comprising the following steps:

[0041] 1) Raw material: 12.5 tons of electrolytic nickel plate with a purity of not less than 99.96%, cut into nickel plate strips with a width of 200-700mm by using a cutting machine, wherein the length of the nickel plate strip is determined according to the length of the consumable electrode;

[0042] 2) Consumable electrode preparation: two consumable electrodes are prepared by using the cut electrolytic nickel plate strips, i.e. one 7.7-ton φ700x5000mm round electrode and one 4.8-ton φ700x3100mm round electrode; the preparation steps of the consumable electrode are as follows:

[0043] 2-1) The cut electrolytic nickel plate strips are laid one by one on the shaping frame, and the length direction of each electrolytic nickel plate strip is argon arc welded, wherein the current during argon arc welding is 180-260A, the argon flow rate is 10-15L / min, the weld length is 10mm, and the welding quality of the welding position is ensured;

[0044] 2-2) Tighten the hinges and use 50mm wide and 3.0mm thick packing strips to bundle and pack the items, with the packing strips spaced 400mm apart. The packing strips are pure nickel strips.

[0045] like Figure 1 As shown, the specific structure of the shaping frame 1 is as follows: The shaping frame 1 includes a base frame 1-1, and multiple arc-shaped frames 1-2 are evenly distributed along the length of the base frame 1-1. The openings of the arc-shaped frames 1-2 are upward, and the lower ends of the arc-shaped frames 1-2 are fixed to the base frame 1-1. Cut electrolytic nickel strips are laid on the arc-shaped support surface of the arc-shaped frames 1-2 in a sequence of increasing width and then decreasing width, and then welded for shaping. Specifically, the base frame 1-1 uses two parallel side uprights 1-11 and a longitudinal bar 1-12 parallel between the two side uprights 1-11. Multiple horizontal bars 1-13 are evenly distributed above the side uprights 1-11 and the longitudinal bars 1-12, and the multiple horizontal bars 1-13 fixedly connected to the side uprights 1-11 and the longitudinal bars 1-12 fix the two side uprights 1-11 and the longitudinal bars 1-12. The components are integrated into one unit. Specifically, the arc-shaped frame 1-2 includes two parallel columns 1-21 and an arc-shaped plate 1-22 with its opening facing upward and fixedly connected to the side wall of the corresponding side column 1-21. The lower ends of the two columns 1-21 are fixed to the outer wall of the corresponding side plate 1-11. The lower end of the arc-shaped plate 1-22 is fixedly connected to the side plate 1-11 and the longitudinal rod 1-12. A support rod 1-23 with its lower end fixedly connected to the side wall of the longitudinal rod 1-12 is fixed on the inner side wall of the column 1-21. When shaping the circular electrode, nickel strips of the same length are selected according to the length of the circular electrode. They are laid from bottom to top in order of width from small to large and then back to small. Each layer is welded and fixed to the nickel strips on the corresponding side. Under the support and guidance of the arc surface of the arc plate 1-22, the circular electrode is formed after welding.

[0046] 3) Melting: The two round electrodes are melted twice using a vacuum consumable arc melting method. The first melting uses a φ760mm copper crystallizer, and the second melting uses a φ840mm copper crystallizer. The advantages of using two melting methods are as follows: (1) It can ensure more complete gas emission and greatly reduce the conditions for the formation of pores inside the nickel ingot; (2) Harmful residual elements are easily volatilized under high temperature melting, thereby achieving a purification effect; (3) The two melting methods also make the composition of the ingot more uniform.

[0047] Specifically, in the first melting, a φ700*5000mm round electrode is loaded into a φ760mm copper crystallizer, the φ700*5000mm round electrode is welded and fixed at the lower end of the auxiliary electrode, the furnace is opened after the welding position is cooled and solidified, the φ700*5000mm round electrode is completely melted, the furnace cover is opened after cooling for about two hours, a φ700*3100mm round electrode is loaded into the φ760mm copper crystallizer, and the φ700*3100mm round electrode is welded and fixed at the lower end of the auxiliary electrode, the furnace is opened after the welding position is cooled and solidified, and the furnace is opened after the φ700*3100mm round electrode is completely melted and cooled for at least 7 hours, completing the first melting of the two round electrodes; specifically, the vacuum degree in the vacuum consumable arc melting furnace before the auxiliary electrode is welded with the φ700*5000mm round electrode and the φ700*3100mm round electrode is ≤1Pa, the welding current when the auxiliary electrode is welded with the two round electrodes is 3-12kA, the welding voltage is 20-40V, and the cooling time after welding is ≥30min; the vacuum degree in the furnace before the first melting is ≤4Pa, the air leakage rate is ≤1Pa / min, and the arc stabilizing current is 10A; the current in the melting stable stage is 15-19kA, the voltage is 32-38V, the vacuum degree is ≤10Pa, the supplement is started at a position 80mm away from the head during melting, the current is reduced to 10KA at a speed of 2KA / min, and then reduced to 4KA at a speed of 1KA / min, and the melting current of 4KA is used until the melting is completed;

[0048] After the nickel ingot obtained after the first melting is turned into a flat head, it is loaded into a φ840mm copper crystallizer, the nickel ingot is welded and fixed at the lower end of the auxiliary electrode, the furnace is opened after the welding position is cooled and solidified, and the furnace is opened after the nickel ingot is completely melted and cooled for at least 10 hours, completing the second melting; the vacuum degree in the vacuum consumable arc melting furnace before the auxiliary electrode is welded with the nickel ingot obtained after the first melting is ≤1Pa, the welding current is 4-12kA, the welding voltage is 20-40V, and the cooling time after welding is ≥30min; the vacuum degree in the furnace before the second melting is ≤2Pa, the air leakage rate is ≤1Pa / min, and the arc stabilizing current is 12A; the current in the melting stable stage is 25-30kA, the voltage is 33-40V, the vacuum degree is ≤8Pa, the supplement is started at a position 150mm away from the head during melting, the current is reduced to 16KA at a speed of 2KA / min during the supplement stage, and then reduced to 4KA at a speed of 1KA / min, and the melting current of 4KA is used until the melting is completed;

[0049] The arc temperature in the vacuum consumable arc melting process is as high as 1600-1800 DEG C, the electrode is melted under the action of the arc, and gas is discharged, and the molten metal in the molten pool can absorb the environmental gas, and the current and voltage parameters in the scheme are used to appropriately slow down the melting speed, the melting process slowly discharges gas, and the discharged gas can be timely discharged through the vacuum system, so that the molten pool is in a relatively pure environment state during the melting process, so that the porosity defects in the nickel ingot are eliminated.

[0050] The relatively large arc current parameter setting is based on the relatively large specific gravity of the metal nickel, and the arc current in the scheme can make the liquid metal in the molten pool flow under the action of electromagnetic stirring, so as to finally ensure the uniformity of the composition of the nickel ingot.

[0051] The vacuum consumable arc melting crystallizer adopts external water cooling, the metal liquid in the crystallizer gradually solidifies from the edge to the center, the liquid metal in the edge continuously absorbs the liquid metal in the center to supplement, so as to form a hole at the center position of the cross section of the upper part of the ingot, and the supplementing process in the scheme is used to slow down the melting speed in the later stage of melting, and the liquid metal in the center is continuously supplemented during the gradual solidification of the metal in the edge, so that the depth of the center hole is greatly reduced, and the yield of the ingot is improved.

[0052] 4) First peeling and grinding: the nickel ingot obtained by melting is placed on the lathe for multi-pass lathe peeling, the feed amount is 1-3 mm each time, the local surface defect of the nickel ingot is turned and peeled or ground by the grinding wheel after the whole nickel ingot is peeled, the treated part should be smooth, without platform and corners, the depth-width ratio of the defect position on the upper surface of the nickel ingot is not greater than 1:6, the treatment depth is not greater than 10 mm, and the head and bottom chamfer of the nickel ingot is 40*50-70 mm;

[0053] 5) Sampling and chemical composition detection: take the chip-shaped and block-shaped samples on the outer circular wall within the range of 230-280 mm from the head and bottom of the nickel ingot, the samples should not be oxidized, the number of each chip sample is not less than 25 g, the block sample with a length of 100 mm and a diameter of φ3-φ5 is taken, and the analysis of residual elements meets the standard of GB / T5235-2021;

[0054] 6) Riser cutting: the nickel ingot is positioned by ultrasonic flaw detection, and the nickel ingot riser is cut by a sawing machine;

[0055] 7) Forging: the nickel ingot is forged by free forging, the heating temperature of the nickel ingot is 1100 DEG C, the forging size is δ160mm*1260mm*L, and a thick slab is formed.

[0056] 8) Second peeling, grinding: adopt multi-pass milling machine to peel the thick slab, each feed amount is 1-3mm, the thick slab should be chamfered along the length direction of four sides, the chamfer is (5-20) mm*45°, the Ra value of the thick slab surface roughness should be not more than 3.2um, after the whole peeling, the local defects on the thick slab surface are removed by grinding wheel polishing, the pit depth after cleaning should be not more than 5mm, the cleaning width and cleaning length should be not less than 10 times of the pit depth, the pit edge generated by grinding is required to be smoothly transitioned with the plate surface;

[0057] 9) Hot rolling: the heating temperature of the thick slab is 1100℃ when hot rolling, and the size after hot rolling is δ5.0mm*1300mm*L, forming thick nickel coil;

[0058] 10) Stress relief annealing: the thick nickel coil after hot rolling is continuously annealed at 800℃;

[0059] 11) Surface treatment: adopt pickling to remove the oxide layer on the surface of the thick nickel coil;

[0060] 12) Cold rolling: adopt 20-roll cold rolling machine to cold roll the thick nickel coil after surface treatment, the size after cold rolling is δ1.0mm*1300mm*L or δ1.5mm*1300mm*L, forming thin nickel coil;

[0061] 13) Annealing: adopt 800℃ argon protection to continuously anneal the thin nickel coil after cold rolling;

[0062] 14) Surface treatment: the thin nickel coil after annealing is pickled to surface brightening;

[0063] 15) Sampling, performance detection: the head and tail of the thin nickel coil after surface treatment are cut and sampled, and the transverse mechanical property and longitudinal mechanical property are detected.

[0064] The technical scheme is based on the vacuum consumable arc furnace, and the prepared large single heavy nickel coil is melted by adopting secondary melting mode, and the technical parameters are optimized and improved, so that the problems of large single heavy nickel coil preparation difficulty, easy to produce pores, inclusions and deep shrinkage hole under the traditional preparation process are solved, the quality and yield of the nickel ingot after melting are improved, the electrolytic nickel strip after cutting is prepared into consumable electrode under the support of the bottom frame and the multiple arc-shaped frames distributed along the length direction of the bottom frame, and the molding quality is improved, the support and shaping conditions are provided for the rapid molding of the required outer contour shape of the consumable electrode, the melting parameters are optimized when two circular electrodes are melted in the vacuum consumable arc furnace, technical support is provided for the improvement of the quality of the nickel ingot, and conditions are provided for the preparation of the large single heavy nickel coil, the preparation process is simple, the cost is low, the quality of the nickel coil is guaranteed, and the preparation of the large single heavy high-quality wide nickel coil product is especially suitable.

[0065] It will be obvious to a person skilled in the art that the application is not limited to the details of the foregoing exemplary embodiments and can be implemented in other concrete forms without departing from the spirit or essential characteristics of the application. The embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. No reference signs in the claims should be considered as limiting the scope of the claims to the identity of the reference signs therein.

[0066] Furthermore, it should be understood that although the description is made on the basis of the embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that those skilled in the art can understand.

Claims

1. A process for producing a large single weight wide format nickel coil of grade 1.10T characterized in that Comprise the following steps: 1) raw materials: using 12.5 tons of electrolytic nickel plate with purity not less than 99.96%, using the cutting bed to cut into 200-700mm width of nickel plate strip; 2) consumable electrode preparation: using the cutting electrolytic nickel plate strip to prepare two consumable electrodes, i.e. 7.7 tons of size φ700x5000mm round electrode and 4.8t of size φ700x3100mm round electrode each; 3) melting: using vacuum consumable arc melting method to melt the two round electrodes twice, wherein, the first melting uses φ760mm copper crystallizer, the second melting uses φ840mm copper crystallizer; 4) first skinning and grinding: the nickel ingot obtained by melting is placed on the lathe for multi-pass lathe skinning, each feed amount is 1-3mm, the nickel ingot is skinned after the whole, the local surface defect is turned or the grinding wheel is polished to remove, the treatment part should be smooth, without platform and angle, the depth-width ratio of the defect position on the upper surface of the nickel ingot is not more than 1:6, the treatment depth is not more than 10mm, the head and bottom of the nickel ingot are chamfered 40x50-70mm; 5) sampling and chemical composition detection: taking the scrap and block samples from the outer circular wall within the range of 230-280mm from the head and bottom of the nickel ingot, the samples should not be oxidized, each scrap sample is not less than 25g in quantity, the block sample is 100mm in length and φ3-φ5 in diameter, the analysis of residual elements meets the standard GB / T5235-2021; 6) cutting off the riser: the nickel ingot is positioned by ultrasonic flaw detection, and the nickel ingot riser is cut off by sawing machine; 7) forging: the nickel ingot is forged by free forging, the heating temperature of the nickel ingot is 1100℃, the forging size is δ160mmx1260mmxL, and the thick slab is formed; 8) second skinning and grinding: the thick slab is skinned by multi-pass milling machine, each feed amount is 1-3mm, the thick slab should be chamfered along the length direction of four sides, the chamfer is (5-20)mmx45°, the Ra value of the surface roughness of the thick slab should be not more than 3.2μm, the local defect of the thick slab surface is polished by grinding wheel after the whole skinning, the pit depth after cleaning should be not more than 5mm, the cleaning width and length should be not less than 10 times of the pit depth, the pit edge generated by grinding is required to be smoothly transitioned with the plate surface; 9) hot rolling: the heating temperature of the thick slab during hot rolling is 1050-1150℃, and the size after hot rolling is δ5.0mmx1300mmxL, and the thick nickel coil is formed; 10) stress relief annealing: the thick nickel coil after hot rolling is continuously annealed at 750-850℃; 11) surface treatment: the oxide layer on the surface of the thick nickel coil is removed by pickling; 12) cold rolling: the thick nickel coil after surface treatment is cold rolled by 20-roll cold rolling machine, the size after cold rolling is δ1.0mmx1300mmxL or δ1.5mmx1300mmxL, and the thin nickel coil is formed; 13) annealing: the thin nickel coil after cold rolling is continuously annealed by argon protection at 750-850℃; 14) surface treatment: the thin nickel coil after annealing is pickled to brighten the surface; 15) Sampling, performance testing: after surface treatment, the thin nickel coil head and tail are cut and sampled, and the transverse and longitudinal mechanical properties are tested; In the step 2), the preparation step of the consumable electrode is specifically as follows: 2-1) the cut electrolytic nickel strip is laid on the shaping frame (1) layer by layer, and each piece of the electrolytic nickel strip is connected by argon arc welding in the length direction, wherein the current of the argon arc welding is 180-260 A, the argon flow is 10-15 L / min, and the weld length is 10 mm; 2-2) the chain is tightened and packed with a packing strip with a width of 50 mm and a thickness of 3.0 mm, the packing strip is a pure nickel strip, and the interval of the packing strips is 400 mm; the shaping frame (1) comprises a base frame (1-1), a plurality of arc-shaped frames (1-2) are uniformly distributed along the length direction of the base frame (1-1), the opening of the arc-shaped frame (1-2) is upwardly arranged, and the lower end of the arc-shaped frame (1-2) is fixed on the base frame (1-1), the cut electrolytic nickel strip is laid on the arc-shaped support surface of the arc-shaped frame (1-2) according to the laying order from small to large and then to small, and then welded and shaped; the base frame (1-1) comprises two parallel side stand plates (1-11) and a longitudinal rod (1-12) arranged between the two side stand plates (1-11), a plurality of transverse rods (1-13) are uniformly distributed above the side stand plates (1-11) and the longitudinal rod (1-12), and the plurality of transverse rods (1-13) fixedly connected with the side stand plates (1-11) and the longitudinal rod (1-12) fixedly connect the two side stand plates (1-11) and the longitudinal rod (1-12) into one body; the arc-shaped frame (1-2) comprises two parallel stand columns (1-21) and an arc-shaped plate (1-22) with an upward opening and fixedly connected with the side wall of the corresponding side stand column (1-21), the lower end of the two stand columns (1-21) is fixed on the outer wall of the corresponding side stand plate (1-11), the lower end of the arc-shaped plate (1-22) is fixedly connected with the side stand plate (1-11) and the longitudinal rod (1-12), and the inner side wall of the stand column (1-21) is fixed with a support rod (1-23) with a lower end fixedly connected with the side wall of the longitudinal rod (1-12); In the above step 3), in the first time of smelting, a φ700*5000mm round electrode is loaded into a φ760mm copper crystallizer, the φ700*5000mm round electrode is welded and fixed at the lower end of the auxiliary electrode, the furnace is opened after the welding position is cooled and solidified, the φ700*5000mm round electrode is completely smelted, the furnace cover is opened after the cooling for about two hours, a φ700*3100mm round electrode is loaded into the φ760mm copper crystallizer, and the φ700*3100mm round electrode is welded and fixed at the lower end of the auxiliary electrode, the furnace is opened after the welding position is cooled and solidified, the φ700*3100mm round electrode is completely smelted, the furnace is opened after the cooling for at least 7 hours, and the first time of smelting of the two round electrodes is completed; the nickel ingot obtained after the first time of smelting is turned into a flat head by a lathe, loaded into a φ840mm copper crystallizer, welded and fixed at the lower end of the auxiliary electrode, the furnace is opened after the welding position is cooled and solidified, the nickel ingot is completely smelted, the furnace is opened after the cooling for at least 10 hours, and the second time of smelting is completed; Before the welding of the auxiliary electrode with the φ700*5000mm round electrode and the φ700*3100mm round electrode, the vacuum degree in the vacuum consumable arc smelting furnace is less than or equal to 1Pa, the welding current is 3-12kA, the welding voltage is 20-40V, and the cooling time after welding is greater than or equal to 30min; Before the welding of the auxiliary electrode with the nickel ingot obtained after the first time of smelting, the vacuum degree in the vacuum consumable arc smelting furnace is less than or equal to 1Pa, the welding current is 4-12kA, the welding voltage is 20-40V, and the cooling time after welding is greater than or equal to 30min; Before the first time of smelting, the vacuum degree in the furnace is less than or equal to 4Pa, the air leakage rate is less than or equal to 1Pa / min, and the arc stabilizing current is 10A; in the stable smelting stage, the current is 15-19kA, the voltage is 32-38V, the vacuum degree is less than or equal to 10Pa, the smelting is started to be supplemented at a position 80mm away from the head, the current is decreased to 10kA at a speed of 2kA / min in the supplementing stage, then decreased to 4kA at a speed of 1kA / min, and the smelting is ended by using the smelting current of 4kA; Before the second time of smelting, the vacuum degree in the furnace is less than or equal to 2Pa, the air leakage rate is less than or equal to 1Pa / min, and the arc stabilizing current is 12A; in the stable smelting stage, the current is 25-30kA, the voltage is 33-40V, the vacuum degree is less than or equal to 8Pa, the smelting is started to be supplemented at a position 150mm away from the head, the current is decreased to 16kA at a speed of 2kA / min in the supplementing stage, then decreased to 4kA at a speed of 1kA / min, and the smelting is ended by using the smelting current of 4kA.

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