A production process for large-size QFe0.1 forged flat strip

Abstract

The present invention discloses a production process of a large-size QFe0.1 forged flat strip. The copper alloy strip has an iron content of 0.075% to 0.14% by weight, a phosphorus content of 0.025% to 0.04% by weight, has high hardness and conductivity, and meets the performance requirements of the lead frame. The present invention adopts the process of upward continuous casting → continuous extrusion → multi-pass rolling (rough rolling) → annealing → multi-pass rolling (finishing rolling) → loose coiling → annealing → cleaning → finishing → longitudinal shearing and slitting → finished product packaging to produce the QFe0.1 forged flat strip, which can refine the grain structure; by improving the extrusion die and the extrusion wheel groove, the problem of edge tearing, unsaturation and bubbles in the traditional process of extruding the QFe0.1 wide alloy strip blank is solved. Through the above process improvements, the forged flat strip produced has no edge tearing, no bubbles, and a smooth surface, and occupies a small area, has a small investment, and has a good working environment. The strip quality meets the performance requirements of mid-to-high-end products, and the product production can achieve high quality and low cost.

Description

Technical Field

[0001] The invention relates to the technical field of nonferrous metal processing, and in particular to a production process of a large-size QFe0.1 forged flat strip. Background Art

[0002] At present, domestic copper strip processing enterprises generally use horizontal continuous casting or semi-continuous casting hot rolling to organize production of QFe0.1 forged flat strips. Among them, the horizontal continuous casting process route is an online solid solution of the ingot, and the thickness should not be too large, so as not to reduce the cooling rate and cause the precipitation of large particles. In addition, the Cu-Fe-P alloy has poor thermal conductivity, poor fluidity, deep liquid cavity, and is prone to shrinkage, density and low comprehensive mechanical properties between grains. Therefore, the thickness of the ingot cannot be too small. Therefore, the production of copper strips in the horizontal continuous casting process route is affected by many factors such as the quality of the strip, the operation level of the rolling mill, the rolling process, the pass distribution rate, and the bell-type furnace annealing process. The production technology is difficult and has many defects, and can only meet the needs of low-end lead frame products. The semi-continuous casting hot rolling process route has a large production capacity, a dense internal structure of the hot-rolled billet, and a large width, which can meet the needs of high-end lead frame products, but its equipment investment is huge, energy consumption is high, the production environment is poor, the floor space is large, the process yield is low, and multiple equipment are required, and the return on investment is low. In addition, there are a few companies that use copper production technology and molds ( Figure 5 ) produces QFe0.1 forged flat strips, but QFe0.1 copper alloy has poor fluidity and high hardness compared to red copper. The production process and mold using red copper to produce QFe0.1 forged flat strips will result in edge tearing and unsaturation, and the forged flat strips have a large amount of internal bubbles after rolling, and the quality of the finished product cannot be guaranteed. Summary of the invention

[0003] The purpose of the present invention is to solve the above-mentioned technical problems existing in the existing production process of QFe0.1 forged flat strip, and to provide a production process of large-size QFe0.1 forged flat strip with small footprint, small investment, good working environment, and strip quality that meets the performance requirements of mid-to-high-end products.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A production process of a large-size QFe0.1 forged flat strip, wherein the QFe0.1 forged flat strip has an iron content of 0.075-0.14%, a phosphorus content of 0.025-0.04%, and the remainder is a copper-based alloy, and the production process comprises the following steps:

[0006] Step 1: Upper casting rod: melt and cast the raw materials into φ30 alloy copper rod in an upper casting furnace according to the alloy ratio;

[0007] Step 2: Continuous extrusion: Design an extrusion die so that the φ30 alloy copper rod rotates with the extrusion wheel of the continuous extruder and is fed into the extrusion die for continuous extrusion to form a 320*15mm strip blank;

[0008] The extrusion die comprises a flow divider die and a forming die, wherein the flow divider die is formed by splicing a first flow divider die and a second flow divider die of the same structure, wherein the middle section and both ends of the material inlet of the flow divider die are straight structures of equal width after splicing, and a triangular flow divider block is vertically arranged in the middle of the inner surface of the first flow divider die and the second flow divider die, and the two triangular flow divider blocks have the same structure and are of the same height as the flow divider die; the middle part of the extrusion port of the forming die is a straight straight I-shaped structure, and inverted quadrangular pyramid structures for secondary flow diversion are symmetrically arranged at both ends of the extrusion port, and the inverted quadrangular pyramid structure is connected with the I-shaped structure and is integrally formed;

[0009] Step 3: Flat strip rolling: The roughing mill performs 7 reversible rolling passes;

[0010] Step 4: Hood annealing: anneal at a furnace temperature of 530-550°C for 6 hours, keep warm for 12 hours, and take out of the furnace at 70°C to refine the elongated grains produced by rolling and soften the product for subsequent rolling.

[0011] Step 5: Surface cleaning: The strip after annealing in step 4 is subjected to conventional pickling and degreasing to remove surface ash and oxides.

[0012] Step 6: Multi-pass rolling: The finishing mill can perform reversible rolling for 4-6 passes;

[0013] Step 7, unwinding and unloading the roll;

[0014] Step 8: Hood annealing: anneal at a furnace temperature of 500-530°C for 6 hours, keep warm for 12 hours, and take out of the furnace at 70°C;

[0015] Step 9, surface cleaning and grinding: the strip after annealing in step 8 is subjected to conventional pickling and degreasing, then water washing, grinding and polishing, and finally passivation treatment until the surface roughness of the strip Ra is less than 0.2μm;

[0016] Step 10: Straightening and finishing: eliminate internal stress and make the strip shape within 5I;

[0017] Step 11: Cut into strips;

[0018] Step 12: Packaging.

[0019] As a preferred embodiment of the present invention, in the above step 1, the upper casting rod has a guide rod speed of 1700 mm / min, an intercept of 6 mm, a cooling water inlet temperature of ≤30°C, and a cooling water outlet temperature of ≤45°C.

[0020] Furthermore, the triangular diverter block forms a slope of ∠1:80 from the material inlet of the diverter die to the contact surface between the diverter die and the forming die.

[0021] Furthermore, in the continuous extrusion step, the wheel groove of the extrusion wheel is deepened to 35 mm, and an inward buckling treatment is performed, and the thickness of the copper layer in the wheel groove of the extrusion wheel is increased from 3 mm to 4 mm.

[0022] Furthermore, in step nine, the washing, grinding and polishing are performed by brushing the surface of the strip with deionized water from front to back using a grinding brush with gradually decreasing bristle hardness.

[0023] Furthermore, in step eleven, the slitting width of the sheared strips is 20-300 mm.

[0024] Compared with the existing production process of QFe0.1 forged flat strip, the present invention has the following beneficial effects:

[0025] 1. The present invention adopts the process flow of upward continuous casting → continuous extrusion → multi-pass rolling (rough rolling) → annealing → multi-pass rolling (finishing rolling) → unwinding → annealing → cleaning → finishing → longitudinal shearing and slitting → finished product packaging to produce QFe0.1 forged flat strips, which can refine the grain structure, eliminate the defects of the cast structure of the upward copper rod, and do not need to remove the oxide scale (milling surface); by improving the extrusion die of the continuous extrusion step, the problem of edge tearing and unsaturation of the QFe0.1 wide alloy strip blank extruded by the traditional process is solved; by deepening the wheel groove of the extrusion wheel in the continuous extrusion step to 35mm and performing an inner buckle treatment, the thickness of the copper layer in the wheel groove of the extrusion wheel is increased from 3mm to 4mm, the renewal frequency of this part of the copper layer is reduced, oxidized copper impurities and air are prevented from entering the extruded finished product, and bubbles in the alloy copper strip blank are eliminated. Through the above process improvements, the forged flat belt produced has no torn edges, no bubbles, and a smooth surface. It also occupies a small area, requires low investment, and has a good working environment. The strip quality meets the performance requirements of mid-to-high-end products, and product production can achieve high quality and low cost.

[0026] 2. The flat strip rolling process of the present invention adopts 7 passes for rolling, which solves the problem of obvious hardening of the alloy after rolling and ensures the stability of the thickness tolerance of the flat strip finished product after rolling.

[0027] 3. The surface cleaning and grinding step of the present invention grinds and polishes the strip material while washing the surface with water, so that the strip surface is clean without defects such as peeling and white spots, and the flatness of the strip surface is further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of the extrusion die structure of the continuous extrusion step of the present invention;

[0029] Figure 2 for Figure 1 Schematic diagram of the structure of the middle split flow module;

[0030] Figure 3 for Figure 1 Schematic diagram of the structure of the middle forming die;

[0031] Figure 4 for Figure 1 Schematic diagram of the slope of the middle triangular diverter block;

[0032] Figure 5 It is a structural schematic diagram of the existing die splitter die and forming die of the continuous extruder;

[0033] Figure 6 Schematic diagram of optimized structure of extrusion wheel for continuous extrusion steps;

[0034] Figure 7 This is a metallographic diagram of a QFe0.1 forged flat strip product produced by the process of Example 1 of the present invention;

[0035] Figure 8 This is a metallographic image of a QFe0.1 forged flat strip product produced by the semi-continuous casting and hot rolling process of Comparative Example 1;

[0036] Fig. 9 This is a physical picture of the torn edge of QFe0.1 extruded strip produced using copper production molds and extrusion technology;

[0037] Fig.10 This is a physical picture of the bubbles in the QFe0.1 extruded strip produced using copper production dies and extrusion technology;

[0038] Fig.11 This is a physical picture of a QFe0.1 extruded strip produced by the process of Example 1 of the present invention;

[0039] Figure numerals: 1. Diverter die: 1-1, first diverter die, 1-2, second diverter die; 2. Forming die; 3. Triangular diverter block; 4. Inverted tetrahedral pyramid structure; 5. Diverter die material inlet; 6. Forming die extrusion outlet; 7. Extrusion wheel groove. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be further described below through specific embodiments in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on these embodiments, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the present invention.

[0041] Reference Figure 5The die of the continuous extruder is designed for the production of copper conductive copper bars, and is divided into a diverter die 1 and a forming die 2. When in use, the diverter die 1 is placed on the top of the forming die 2, and the copper rod enters the diverter die 1 and is discharged from the forming die 2. The middle section of the existing diverter die material inlet 5 is a straight structure, and both ends are conical feeding ends. The extrusion port 6 of the forming die is a straight straight I-shaped rounded hole. When it is used to produce wide alloy strip products with a width of more than 300 mm, it will cause tearing, unsaturation and other phenomena, and the product quality cannot be guaranteed.

[0042] Reference Figure 1-Figure 4 In the following embodiments of the present invention, an improved extrusion die is used, and the extrusion wheel groove 7 is deepened to 35 mm, and an inner buckle treatment is performed, and the thickness of the copper layer in the extrusion wheel groove is increased from 3 mm to 4 mm ( Figure 6 ). The extrusion die includes a diverter die 1 and a forming die 2. The diverter die 1 is formed by splicing a first diverter die 1-1 and a second diverter die 1-2 with the same structure. After splicing, the middle section and both ends of the diverter die material inlet 5 are straight structures with equal width. A triangular diverter block 3 is provided in the vertical direction in the middle of the inner surface of the first diverter die 1 and the second diverter die 2. The two triangular diverter blocks 3 have the same structure and are at the same height as the diverter die 1; the long side length of the triangular diverter block 3 accounts for 1 / 2 of the total length of the diverter die material inlet 5. The triangular diverter block 3 is chamfered in the width direction of the diverter die 1, and the triangular diverter block 3 is inclined at ∠1:80 from the diverter die material inlet 5 to the contact surface between the diverter die 1 and the forming die 2. The middle part of the forming die extrusion outlet 6 is a straight I-shaped structure, and inverted quadrangular pyramid structures 4 for secondary diversion are symmetrically arranged at both ends of the extrusion outlet. The total length of the two inverted quadrangular pyramid structures 4 accounts for 1 / 2 of the total length of the forming die extrusion outlet 6. The inverted quadrangular pyramid structure 4 is connected to the I-shaped structure and formed as one piece, and chamfers are arranged at the four corners of the inverted quadrangular pyramid structure 4.

[0043] Example 1

[0044] A large-size QFe0.1 forged flat strip of this embodiment has a copper-based alloy as the main component, and alloy elements iron and phosphorus are added according to weight percentage, wherein the addition range of iron is 0.0978-0.128%, and the addition range of phosphorus is 0.0288-0.0476%, so that the copper alloy has higher hardness and conductivity, meeting the growing performance requirements of the lead frame. The production process is as follows:

[0045] Step 1: Upper casting rod: The raw materials are melted and cast in the upper casting furnace according to the alloy ratio to form a φ30 alloy copper rod. The rod casting speed is 1700mm / min, the intercept is 6mm, the cooling water inlet temperature is ≤30℃, and the outlet water temperature is ≤45℃.

[0046] Step 2: Continuous extrusion: Using the above extrusion die, the φ30 copper rod rotates with the extrusion wheel, and the rod-shaped blank is fed into the extrusion die for continuous extrusion to form a 320*15mm strip blank.

[0047] Step 3: Multi-pass rolling: The rough rolling mill can perform 7 reversible rolling passes.

[0048] Step 4: Hood annealing: anneal at a furnace temperature of 530°C for 6 hours, keep warm for 12 hours, and take out of the furnace at 70°C to refine the elongated grains produced by rolling and soften the product for subsequent rolling.

[0049] Step 5: Surface cleaning: The strip after annealing in step 4 is subjected to conventional pickling and degreasing to remove surface ash and oxides.

[0050] Step 6: Multi-pass rolling: The finishing mill can perform 4 reversible rolling passes.

[0051] Step 7: Unwind and unload the coil: During the rolling process, high tension can ensure the strip shape, but during the annealing process, excessive tension can easily cause adhesion, so it is necessary to rewind and unwind the coil.

[0052] Step 8: Hood annealing: anneal at a furnace temperature of 500°C for 6 hours, keep warm for 12 hours, and take out of the furnace at 70°C to fully release the internal stress generated by rolling and prevent cracks from occurring during forging or stamping of the strip.

[0053] Step 9, surface washing and grinding: The strip after annealing in step 8 is subjected to conventional pickling and degreasing, and then the surface of the strip is brushed, ground and polished with deionized water using a grinding brush with gradually decreasing bristle hardness from front to back, and finally passivated to make the strip surface clean without defects such as peeling and white spots, greatly improving the flatness of the strip surface, and the obtained strip surface roughness (Ra) is less than 0.2μm.

[0054] Step 10: Straightening and finishing: eliminate internal stress and ensure the plate shape.

[0055] Step 11: Cut into strips: cutting width 20-300mm.

[0056] Step 12: Packaging.

[0057] The average grain intercept of QFe0.1 forged flat strip produced by this process is 8.365μm, the surface roughness is 0.159μm, the conductivity is 87 / %IACS, the plate type is 3I, and the metallographic diagram is shown in Figure 7 , the actual picture of the extruded strip is shown in Fig.11 It can be seen that the finished forged flat belt has no torn edges, no bubbles, and a smooth surface, which can meet the performance requirements of mid-to-high-end products.

[0058] Comparative Example 1

[0059] Existing semi-continuous casting hot rolling process:

[0060] Step 1: Semi-continuous casting: The raw materials are melted and cast in a semi-continuous casting furnace according to the alloy ratio to form a 430*245*5700 ingot, and the head and tail are cut to 350mm each.

[0061] Step 2, hot rolling: hot rolling mill rolls 450*16mm through 7 passes.

[0062] Step 3: Double-sided milling: Mill the upper surface by 0.4mm and the lower surface by 0.6mm to remove the oxide scale.

[0063] Step 4: Multi-pass rolling: The rough rolling mill can perform 7 reversible rolling passes.

[0064] Step 5: Hood annealing: anneal at a furnace temperature of 530°C for 6 hours, keep warm for 12 hours, and take out of the furnace at 70°C to refine the elongated grains produced by rolling and soften the product for subsequent rolling.

[0065] Step 6: Surface cleaning: The strip after annealing in step 5 is subjected to conventional pickling and degreasing to remove surface ash and oxides.

[0066] Step 7: Multi-pass rolling: The finishing mill can perform 4 reversible rolling passes.

[0067] Step 8. Unwinding and unloading the coil: During the rolling process, high tension can ensure the strip shape, but during the annealing process, excessive tension can easily cause adhesion, so it is necessary to rewind and unwind the coil.

[0068] Step 9: Hood annealing: Anneal at a furnace temperature of 500°C for 6 hours, keep warm for 12 hours, and take out of the furnace at 70°C to fully release the internal stress generated by rolling and prevent cracks from occurring during forging or stamping of the strip.

[0069] Step 10, surface washing and grinding: The strip after annealing in step 9 is subjected to conventional pickling and degreasing, and then the surface of the strip is brushed, ground and polished with deionized water using a grinding brush with gradually decreasing bristle hardness from front to back, and finally passivated to make the strip surface clean without defects such as peeling and white spots, greatly improving the flatness of the strip surface, and the obtained strip surface roughness (Ra) is less than 0.2μm.

[0070] Step 11: Straightening and finishing: eliminate internal stress and ensure the plate shape.

[0071] Step 12: Cut into strips: cutting width 20-300mm.

[0072] Step 13: Packaging.

[0073] The average grain intercept of QFe0.1 forged flat strip produced by this process is 13.407μm, the surface roughness is 0.163μm, the conductivity is 86 / %IACS, the plate type is 3I, and the metallographic diagram is shown in Figure 8The process for producing QFe0.1 forged flat strip requires large equipment investment, and the average grain intercept of the obtained product is much larger than that of the process of the present invention.

[0074] Comparative Example 2

[0075] This comparative example is produced using a copper production mold and extrusion process, and its production process is as follows:

[0076] Step 1: Upper casting rod: The raw materials are melted and cast in the upper casting furnace according to the alloy ratio to form a φ30 alloy copper rod. The rod casting speed is 1700mm / min, the intercept is 6mm, the cooling water inlet temperature is ≤30℃, and the outlet water temperature is ≤45℃.

[0077] Step 2: Continuous extrusion: Use a copper extrusion die to make the φ30 copper rod rotate with the extrusion wheel, and feed the rod-shaped billet into the extrusion die for continuous extrusion to form a 320*15mm strip billet.

[0078] Step 3: Multi-pass rolling: The rough rolling mill can perform 7 reversible rolling passes.

[0079] Step 4: Hood annealing: anneal at a furnace temperature of 530°C for 6 hours, keep warm for 12 hours, and take out of the furnace at 70°C to refine the elongated grains produced by rolling and soften the product for subsequent rolling.

[0080] Step 5: Surface cleaning: The strip after annealing in step 4 is subjected to conventional pickling and degreasing to remove surface ash and oxides.

[0081] Step 6: Multi-pass rolling: The finishing mill can perform 4 reversible rolling passes.

[0082] Step 7: Unwind and unload the coil: During the rolling process, high tension can ensure the strip shape, but during the annealing process, excessive tension can easily cause adhesion, so it is necessary to rewind and unwind the coil.

[0083] Step 8: Hood annealing: anneal at a furnace temperature of 500°C for 6 hours, keep warm for 12 hours, and take out of the furnace at 70°C to fully release the internal stress generated by rolling and prevent cracks from occurring during forging or stamping of the strip.

[0084] Step 9, surface washing and grinding: The strip after annealing in step 8 is subjected to conventional pickling and degreasing, and then the surface of the strip is brushed, ground and polished with deionized water using a grinding brush with gradually decreasing bristle hardness from front to back, and finally passivated to make the strip surface clean without defects such as peeling and white spots, greatly improving the flatness of the strip surface, and the obtained strip surface roughness (Ra) is less than 0.2μm.

[0085] Step 10: Straightening and finishing: eliminate internal stress and ensure the plate shape.

[0086] Step 11: Cut into strips: cutting width 20-300mm.

[0087] Step 12: Packaging.

[0088] The QFe0.1 forged flat strip produced by this process has serious strip breakage during the rolling process, and the surface holes and peeling of the finished product are serious, and the quality is unqualified ( Figure 9-10 ).

[0089] Example 2

[0090] Step 1: Upper casting rod: The raw materials are melted and cast in the upper casting furnace according to the alloy ratio to form a φ30 alloy copper rod. The rod casting speed is 1700mm / min, the intercept is 6mm, the cooling water inlet temperature is ≤30℃, and the outlet water temperature is ≤45℃.

[0091] Step 2: Continuous extrusion: Using the above extrusion die, the φ30 copper rod rotates with the extrusion wheel, and the rod-shaped blank is fed into the extrusion die for continuous extrusion to form a 320*15mm strip blank.

[0092] Step 3: Multi-pass rolling: The rough rolling mill can perform 7 reversible rolling passes.

[0093] Step 4: Hood annealing: anneal at a furnace temperature of 530°C for 6 hours, keep warm for 12 hours, and take out of the furnace at 70°C to refine the elongated grains produced by rolling and soften the product for subsequent rolling.

[0094] Step 5: Surface cleaning: The strip after annealing in step 4 is subjected to conventional pickling and degreasing to remove surface ash and oxides.

[0095] Step 6: Multi-pass rolling: The finishing mill can perform 6 reversible rolling passes.

[0096] Step 7: Unwind and unload the coil: During the rolling process, high tension can ensure the strip shape, but during the annealing process, excessive tension can easily cause adhesion, so it is necessary to rewind and unwind the coil.

[0097] Step 8: Hood annealing: anneal at a furnace temperature of 500°C for 6 hours, keep warm for 12 hours, and take out of the furnace at 70°C to fully release the internal stress generated by rolling and prevent cracks from occurring during forging or stamping of the strip.

[0098] Step 9, surface washing and grinding: The strip after annealing in step 8 is subjected to conventional pickling and degreasing, and then the surface of the strip is brushed, ground and polished with deionized water using a grinding brush with gradually decreasing bristle hardness from front to back, and finally passivated to make the strip surface clean without defects such as peeling and white spots, greatly improving the flatness of the strip surface, and the obtained strip surface roughness (Ra) is less than 0.2μm.

[0099] Step 10: Straightening and finishing: eliminate internal stress and ensure the plate shape.

[0100] Step 11: Cut into strips: cutting width 20-300mm.

[0101] Step 12: Packaging.

[0102] The QFe0.1 forged flat strip produced by this process has an average grain intercept of 8.565 μm, a surface roughness of 0.189 μm, a conductivity of 86 / % IACS, and a plate type of 3I.

[0103] Example 3

[0104] Step 1: Upper casting rod: The raw materials are melted and cast in the upper casting furnace according to the alloy ratio to form a φ30 alloy copper rod. The rod casting speed is 1700mm / min, the intercept is 6mm, the cooling water inlet temperature is ≤30℃, and the outlet water temperature is ≤45℃.

[0105] Step 2: Continuous extrusion: Using the above extrusion die, the φ30 copper rod rotates with the extrusion wheel, and the rod-shaped blank is fed into the extrusion die for continuous extrusion to form a 320*15mm strip blank.

[0106] Step 3: Multi-pass rolling: The rough rolling mill can perform 7 reversible rolling passes.

[0107] Step 4: Hood annealing: Anneal at a furnace temperature of 530°C for 6 hours, keep warm for 12 hours, and take out of the furnace at 70°C to fully release the internal stress generated by rolling and prevent cracks from occurring during forging or stamping of the strip.

[0108] Step 5: Surface cleaning: The strip after annealing in step 4 is subjected to conventional pickling and degreasing to remove surface ash and oxides.

[0109] Step 6: Multi-pass rolling: The finishing mill can perform 5 reversible rolling passes.

[0110] Step 7: Unwind and unload the coil: During the rolling process, high tension can ensure the strip shape, but during the annealing process, excessive tension can easily cause adhesion, so it is necessary to rewind and unwind the coil.

[0111] Step 8: Hood annealing: anneal at a furnace temperature of 500°C for 6 hours, keep warm for 12 hours, and take out of the furnace at 70°C to refine the elongated grains produced by rolling and soften the product for subsequent rolling.

[0112] Step 9, surface washing and grinding: The strip after annealing in step 8 is subjected to conventional pickling and degreasing, and then the surface of the strip is brushed, ground and polished with deionized water using a grinding brush with gradually decreasing bristle hardness from front to back, and finally passivated to make the strip surface clean without defects such as peeling and white spots, greatly improving the flatness of the strip surface, and the obtained strip surface roughness (Ra) is less than 0.2μm.

[0113] Step 10: Straightening and finishing: eliminate internal stress and ensure the plate shape.

[0114] Step 11: Cut into strips: cutting width 20-300mm.

[0115] Step 12: Packaging.

[0116] The surface roughness of the QFe0.1 forged flat strip produced by this process is 0.143μm, the conductivity is 86 / %IACS, and the plate type is 3I.

Claims

1. A production process for large-size QFe0.1 forged flat strip, characterized in that: In terms of weight percentage, the QFe0.1 forged flat strip has an iron content of 0.075-0.14%, a phosphorus content of 0.025-0.04%, and the rest is copper-based alloy. The production process comprises the following steps: Step 1: Upper casting rod: melt and cast the raw materials into φ30 alloy copper rod in an upper casting furnace according to the alloy ratio; Step 2: Continuous extrusion: Design an extrusion die so that the φ30 alloy copper rod rotates with the extrusion wheel of the continuous extruder and is fed into the extrusion die for continuous extrusion to form a 320*15mm strip blank; The extrusion die comprises a diverter die and a forming die, wherein the diverter die is formed by splicing a first diverter die and a second diverter die of the same structure, wherein the middle section and both ends of the diverter die material inlet after splicing are both straight structures of equal width, and a triangular diverter block is provided in the vertical direction in the middle of the inner surface of the first diverter die and the second diverter die, and the two triangular diverter blocks have the same structure and are at the same height as the diverter die; the middle of the extrusion port of the forming die is a straight I-shaped structure, and inverted quadrangular pyramid structures for secondary diversion are symmetrically provided at both ends of the extrusion port, and the inverted quadrangular pyramid structure is connected with the I-shaped structure and is integrally formed; the triangular diverter block is a ∠1:80 slope from the diverter die material inlet to the contact surface between the diverter die and the forming die; Step 3: Flat strip rolling: The roughing mill performs 7 reversible rolling passes; Step 4: Hood annealing: anneal at a furnace temperature of 530-550°C for 6 hours, keep warm for 12 hours, and take out of the furnace at 70°C; Step 5: Surface cleaning: After annealing in step 4, the strip is subjected to conventional pickling and degreasing to remove surface ash and oxides; Step 6: Multi-pass rolling: The finishing mill can perform reversible rolling for 4-6 passes; Step 7, unwinding and unloading the roll; Step 8: Hood annealing: anneal at a furnace temperature of 500-530°C for 6 hours, keep warm for 12 hours, and take out of the furnace at 70°C; Step 9, surface cleaning and grinding: the strip after annealing in step 8 is subjected to conventional pickling and degreasing, then water washing, grinding and polishing, and finally passivation treatment until the surface roughness of the strip Ra is less than 0.2μm; Step 10: Straightening and finishing: eliminate internal stress and make the strip shape within 5I; Step 11: Cut into strips; Step 12: Packaging.

2. The production process of a large-size QFe0.1 forged flat strip according to claim 1 is characterized in that: In step 1, the upper casting rod has a rod speed of 1700 mm / min, an intercept of 6 mm, a cooling water inlet temperature of ≤30°C, and a cooling water outlet temperature of ≤45°C.

3. The production process of a large-size QFe0.1 forged flat strip according to claim 1 is characterized in that: In the continuous extrusion step, the wheel groove of the extrusion wheel is deepened to 35 mm, and an inward buckle treatment is performed, and the thickness of the copper layer in the wheel groove of the extrusion wheel is increased from 3 mm to 4 mm.

4. The production process of a large-size QFe0.1 forged flat strip according to claim 1 is characterized in that: In step nine, the washing, grinding and polishing are to use a grinding brush with gradually decreasing bristle hardness to brush the surface of the strip with deionized water from front to back.

5. The production process of a large-size QFe0.1 forged flat strip according to claim 1 is characterized in that: In step eleven, the slitting width of the sheared strips is 20-300 mm.

Images