Electrotinning substrate and production method of high-resistance easily-formed low-titanium electrotinning plate

Abstract

The invention discloses an electrotinning substrate and a production method of a high-resistance easily-formed low-titanium electrotinning plate. The electrotinning substrate comprises the following chemical components in percentage by weight: 0.001-0.025% of C, less than or equal to 0.030% of Si, 0.50-0.70% of Mn, 0.010-0.030% of Ti, less than or equal to 0.010% of P, less than or equal to 0.010% of S, less than or equal to 0.005% of N, 0.005-0.040% of Als, less than or equal to 0.06% of Cu, less than or equal to 0.04% of Ni, less than or equal to 0.06% of Cr and less than or equal to 0.05% of Mo. A plating solution in the electrotinning process adopts a PSA electrotinning insoluble anode electrotinning solution, and comprises stannous ions, PSA, EN, ENSA and sodium gluconate. The tinned substrate is not easy to deform and break during cold rolling and annealing; the produced electroplated tin plate is easy to form through cold machining; and the adhesive force of a coating after the produced electroplated tin plate is made into a can is less than or equal to grade 1.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of electroplating, and particularly relates to an electroplated tin substrate and a production method of high-resistance easy-to-form low-titanium electroplated tin plate. BACKGROUND

[0002] The electroplated tin plate (tinplate) is commonly known as tinplate, which is a kind of product with complex production technology, strong technicality, long manufacturing process, high quality requirement and great manufacturing difficulty. Since the electroplated tin plate has good corrosion resistance, easy stamping formability, strong weldability, easy printing coloring, non-toxic plating layer and other characteristics, it is widely used in food packaging and canning industries.

[0003] With the development of the packaging industry, many tinplate food can manufacturers actively develop new can types in order to realize the differentiation of product shapes, and the profiled expanding can is one of the new can types. The profiled expanding can is formed by expanding a certain part of the can body through an expanding die, and has a novel appearance. However, the canning process of the profiled expanding can is relatively complex, and the expanding can is prone to cracking. By adding a small amount of titanium, the formability of the electroplated tin plate is improved, and the electroplated tin plate has high r value and low planar anisotropy, thereby solving the main problem that is particularly concerned by the new can type production enterprises. After adding a small amount of titanium, the temperature of the subsequent continuous annealing (CA) is high, and the hardness of the electroplated tin plate is relatively soft. In order to improve the hardness of the electroplated tin plate, the content of Mn is appropriately increased. However, after the content of Mn is increased, the resistance performance such as sulfur resistance and acid resistance of the electroplated tin plate is reduced, which seriously affects the application of the electroplated tin plate in the canning enterprises.

[0004] In order to overcome the drawbacks caused by the increase of the content of Mn in the low-titanium electroplated tin substrate, the electroplated tin substrate needs to be appropriately electroplated, passivated, rinsed and the like, so as to improve the resistance of the low-titanium electroplated tin plate. Therefore, it is of great practical significance to develop an electroplated tin substrate for controlling the contents of titanium and manganese and a subsequent electroplating tin production method, so as to improve the resistance of the electroplated tin plate. SUMMARY

[0005] The present application provides an electroplated tin substrate and a production method of high-resistance easy-to-form low-titanium electroplated tin plate which is not easy to deform and break during cold rolling and annealing.

[0006] In order to achieve the above-mentioned purpose, the present application provides an electroplated tin substrate, the chemical composition of the electroplated tin substrate includes C: 0.001-0.025%, Si: ≤0.030%, Mn: 0.50-0.70%, Ti: 0.010-0.030%, P: ≤0.010%, S: ≤0.010%, N: ≤0.005%, Als: 0.005-0.040%, Cu: ≤0.06%, Ni: ≤0.04%, Cr: ≤0.06%, Mo: ≤0.05% by weight percentage, and the rest is Fe and inevitable impurities.

[0007] The C content of the present application is selected in the range of 0.001-0.025%. C is one of indispensable elements in steel to increase the strength of steel material, with the increase of carbon content, the Fe in steel increases, and its cold working (stamping, drawing) and welding performance become worse. Cementite is cathode relative to carbon steel (matrix is ferrite), when the carbon content increases, the number and area of cathode increase, and the corrosion current increases accordingly, resulting in the decrease of corrosion resistance.

[0008] The Si content of the present application is ≤0.030%. The higher the Si content of the tin-plated original plate, the greater the ATC value, the Si in the original plate has a significant effect on the corrosion resistance of the tin-plated plate, and the corrosion resistance of the tin-plated plate decreases with the increase of Si content. Therefore, in order to ensure the corrosion resistance of the tin-plated original plate, the Si content is strictly controlled, and the Si content is ≤0.030%.

[0009] The Mn content of the present application is selected in the range of 0.50-0.70%. Mn can strengthen ferrite and increase the hardness of tin-plated substrate. In addition, the addition of manganese in steel can prevent the brittleness of steel caused by sulfur during hot working. Mn has strong affinity with O and is easy to be internally oxidized, and the increase of Mn content will deteriorate the performance of the base material. The higher the Mn content of the tin-plated original plate, the greater the ATC value, and the corrosion resistance of the tin-plated plate decreases.

[0010] The Ti content of the present application is selected in the range of 0.010-0.030%. Ti has strong affinity with O and S, and Ti can change MnS into Ti4C2S2, which is broken during hot rolling to improve the subsequent cold bending performance. Ti can stabilize and reduce the content of O, S and N in steel, improve the uniformity of steel and the forming property of finished product, and reduce the cracking during stamping. However, the Ti content should not be too high, otherwise the continuous annealing temperature of subsequent cold rolling is high, which exceeds the limit capacity of tin-plating annealing unit.

[0011] The P content of the present application is ≤0.010%. Generally speaking, for tin-plated original plate which requires good corrosion resistance, the content of phosphorus is preferably as low as possible, because phosphorus is easy to segregate and leads to the decrease of corrosion resistance.

[0012] The S content of the present application is ≤0.010%. Generally speaking, the smaller the content of sulfur, the better the corrosion resistance. The segregation tendency of S in steel is large, and desulfurization is necessary.

[0013] The synergistic effect of Mn and Ti elements is exerted, and the content of S is reduced. On the other hand, after the addition of Ti, compounds such as Ti4C2S2 and TiN are generated, which stabilize and reduce the content of C, S and N in steel, resulting in the decrease of strength, and the strength is increased by increasing the content of Mn.

[0014] Further, the preparation process of the electro-tinning substrate comprises desulphurization, converter smelting, vacuum treatment, continuous casting, hot rolling, pickling and cold rolling, continuous annealing in sequence; the hot rolled material is subjected to 4-6 passes of cold rolling by the pickling and rolling unit, with a cumulative reduction of 89.0±1.0%, and the electro-tinning substrate is produced after degreasing and 740±15℃ continuous annealing.

[0015] To ensure the recrystallization of the low-titanium steel, the continuous annealing temperature is greater than 720℃, and the annealing temperature limit of the tinning annealing unit is 780℃. When the annealing temperature is higher than 755℃, the thinner tinning substrate is prone to deformation and breakage during annealing.

[0016] The application further provides a production method of the high-resistance and easy-to-form low-titanium electro-tinning plate. The electro-tinning substrate is subjected to degreasing, electro-tinning, reflowing, quenching, passivation, rinsing and oiling in sequence. In the electro-tinning process, the plating solution is PSA electro-tinning insoluble anode plating solution, which comprises stannous ions, PSA, EN, ENSA and sodium gluconate. The content of the stannous ions is 25-30g / L, the content of the PSA is 15-20g / L, the content of the EN is 5-7g / L, the content of the ENSA is 2-4g / L, and the content of the sodium gluconate is 1-2g / L.

[0017] Due to the high Mn content of the substrate, the surface Mn oxide increases. The sodium gluconate is added to the plating solution, which plays a role of complexing the cations on the surface of the substrate and the solution in the plating tank, reduces the Mn-containing small particles on the surface of the substrate, ensures the cleanliness of the substrate surface, and improves the electroplating effect and the cleanliness of the plating layer.

[0018] Further, the passivation solution in the passivation process comprises Na2Cr2O7 and CrO3, wherein the content of the Na2Cr2O7 is 20-23g / L, and the content of the CrO3 is 4.0-6.0g / L.

[0019] The increase of the CrO3 in the passivation system is conducive to improving the content of the CrO3 in the passivation layer and further improving the passivation effect.

[0020] Further, the temperature of the plating solution in the electro-tinning process is 45℃±3℃, the current density is 10-20A / dm 2 .

[0021] Under the same other conditions, the diffusion speed of tin ions and the electrode reaction speed increase with the increase of plating solution temperature, the electrodeposition speed is accelerated, and the production efficiency is improved, but on the other hand, the oxidation speed and the hydrolysis speed of tin ions are accelerated with the increase of plating solution temperature; the current density has great influence on the current efficiency, the plating solution dispersion performance, the plating solution polarization ability, the overpotential, the deposition rate and the like; therefore, the control of the plating solution temperature and the current density can make the tin plating production stable and prevent large fluctuation.

[0022] Further, the pH value of the passivation solution in the passivation process is 3.5±0.2, and the temperature is 42±1℃.

[0023] With the decrease of the pH value, the conversion of Na2Cr2O7 into CrO3 increases, and the increase of CrO3 in the passivation solution system is beneficial to the increase of the CrO3 content in the passivation layer and the further improvement of the passivation effect.

[0024] Further, in the rinsing process, sodium citrate is added to the rinsing water, and the content of the sodium citrate is 30-40mg / L.

[0025] The plating solution system has used sodium gluconate, in order to further improve the rinsing effect, sodium citrate is used instead of sodium gluconate, and the impurity cations such as manganese ions are avoided to affect the resistance of the same substance.

[0026] Further, in the rinsing process, the temperature of the rinsing water is 45±3℃.

[0027] The finished product of the electroplated tin plate prepared in the application has a thickness of 0.21-0.25mm, a hardness value (HR30Tm) of 55-59, an r value of ≥1.6, and a Δr value of ≤0.10; the adhesion of the coating after canning is ≤1 level, and the sulfur resistance and acid resistance performance evaluation is qualified.

[0028] Compared with the prior art, the application has the beneficial effects that the tin-plated substrate of the application is not easy to deform and break during cold rolling and annealing, the electroplated tin plate produced by the application is easy to form during cold working, and the adhesion of the coating of the electroplated tin plate after canning is ≤1 level. DETAILED DESCRIPTION

[0029] The production method of the high-resistance easy-to-form low-titanium electroplated tin plate of the application will be further described in detail below in combination with specific implementation examples.

[0030] Example 1 Production process: desulphurization → converter smelting → vacuum treatment → continuous casting → hot rolling → pickling and cold rolling → continuous annealing → tinning substrate → degreasing → electroplating tin → softening → quenching → passivation → rinsing → oiling process. The chemical composition of the tinning substrate (in wt%) is C: 0.025, Si: 0.020, Mn: 0.70, Ti: 0.030, P: 0.010, S: 0.010, N: 0.005, Als: 0.040, Cu: 0.06, Ni: 0.04, Cr: 0.05, Mo: 0.05, and the rest is Fe and inevitable impurities. The hot rolled material is subjected to pickling after the acid rolling unit, and then cold rolling is carried out by using a rolling mill for 6 passes with a cumulative reduction of 90%. The electroplated tinning substrate is produced after degreasing and continuous annealing at 755°C. The PSA electroplating tin insoluble anode plating system: the content of stannous ions (provided by stannous sulfate) is 30 g / L, the content of PSA (phenol sulfonic acid) is 15 g / L, the content of EN is 7 g / L, the content of ENSA is 2 g / L, the content of sodium gluconate is 2 g / L, the plating bath temperature is controlled in the range of 48°C, and the current density is controlled in the range of 15 A / dm 2 The passivation system: the content of Na2Cr2O7 is 23 g / L, the content of CrO3 is 4.0 g / L, the pH value is 3.7, and the temperature is 43°C. The rinsing system: the content of sodium citrate in the rinsing water is 40 mg / L, and the temperature is 42°C. According to the above production process, the high resistance easy forming low titanium electroplated tin plate with the regulation degree code T-3 is produced, the thickness of the finished product is 0.21 mm, the hardness value (HR30Tm) is 59, the r value is 1.6, the Δr value is 0.10, the adhesion of the coating after canning is 1 level, and the sulfur and acid resistance performance evaluation is qualified.

[0031] Example 2 Production process: desulphurization → converter smelting → vacuum treatment → continuous casting → hot rolling → pickling and cold rolling → continuous annealing → tinning substrate → degreasing → electroplating tin → softening → quenching → passivation → rinsing → oiling process. The chemical composition of the tinning substrate (in wt%) is C: 0.001, Si: 0.030, Mn: 0.50, Ti: 0.010, P: 0.009, S: 0.008, N: 0.004, Als: 0.005, Cu: 0.05, Ni: 0.03, Cr: 0.06, Mo: 0.04, and the rest is Fe and inevitable impurities. The hot rolled material is subjected to pickling after the acid rolling unit, and then cold rolling is carried out by using a rolling mill for 4 passes with a cumulative reduction of 88.0%. The electroplated tinning substrate is produced after degreasing and continuous annealing at 725°C. The PSA electroplating tin insoluble anode plating system: the content of stannous ions (provided by stannous sulfate) is 25 g / L, the content of PSA (phenol sulfonic acid) is 20 g / L, the content of EN is 5 g / L, the content of ENSA is 4 g / L, the content of sodium gluconate is 1 g / L, the plating bath temperature is controlled in the range of 42°C, and the current density is controlled in the range of 20 A / dm2 range. Passivation system: Na2Cr2O7 content of 22 g / L, CrO3 content of 5.0 g / L, pH value of 3.5, temperature of 42°C. Rinsing system: sodium citrate content of 35 mg / L in rinsing water, temperature of 45°C. According to the above production process, the high resistance easy forming low titanium electro-tinned plate with the regulation system code of T-3 was produced, the finished product thickness was 0.23 mm, the hardness value (HR30Tm) was 57, the r value was 2.0, the Δr value was 0.08, the adhesion of the coating after canning was 1 level, and the sulfur resistance and acid resistance performance evaluation was qualified.

[0032] Example 3 Production process: desulfurization → converter smelting → vacuum treatment → continuous casting → hot rolling → pickling and cold rolling → continuous annealing → tinned substrate → degreasing → electro-tinning → fluxing → water quenching → passivation → rinsing → oiling and other processes. The chemical composition of the tinned substrate (by weight %) was C: 0.01, Si: 0.015, Mn: 0.60, Ti: 0.020, P: 0.007, S: 0.009, N: 0.003, Als: 0.020, Cu: 0.03, Ni: 0.02, Cr: 0.03, Mo: 0.02, and the rest was Fe and inevitable impurities. After pickling in the pickling mill set, the hot rolled material was cold rolled by 5 passes by the rolling mill with a cumulative reduction of 89.0%, and the electro-tinned substrate was produced after degreasing and 730°C continuous annealing. The PSA electro-tinning insoluble anode plating system: stannous ion (provided by stannous sulfate) content of 27 g / L, PSA (phenol sulfonic acid) content of 17 g / L, EN content of 6 g / L, ENSA content of 3 g / L, sodium gluconate content of 1.5 g / L, the plating bath temperature was controlled in the range of 45°C, the current density was controlled in the range of 10 A / dm 2 range. Passivation system: Na2Cr2O7 content of 22 g / L, CrO3 content of 5.0 g / L, pH value of 3.5, temperature of 42°C. Rinsing system: sodium citrate content of 35 mg / L in rinsing water, temperature of 45°C. According to the above production process, the high resistance easy forming low titanium electro-tinned plate with the regulation system code of T-3 was produced, the finished product thickness was 0.23 mm, the hardness value (HR30Tm) was 57, the r value was 2.0, the Δr value was 0.08, the adhesion of the coating after canning was 1 level, and the sulfur resistance and acid resistance performance evaluation was qualified.

[0033] Example 4 The production process flow is: desulphurization → converter smelting → vacuum treatment → continuous casting → hot rolling → pickling and cold rolling → continuous annealing → tinning base plate → degreasing → electroplating tin → fluxing → quenching → passivation → rinsing → oiling, etc. The chemical composition of the tinning base plate (in wt%) is C: 0.015, Si: 0.010, Mn: 0.65, Ti: 0.025, P: 0.008, S: 0.007, N: 0.0025, Als: 0.030, Cu: 0.02, Ni: 0.02, Cr: 0.02, Mo: 0.03, and the rest is Fe and inevitable impurities. The hot rolled material is cold rolled by 5 passes with a cumulative reduction of 89.5% after pickling in an acid rolling mill, and the electroplating tin base plate is produced after degreasing and continuous annealing at 740°C. The PSA electroplating tin insoluble anode plating system: the content of stannous ions (provided by stannous sulfate) is 28 g / L, the content of PSA (phenol sulfonic acid) is 16 g / L, the content of EN is 5.5 g / L, the content of ENSA is 3.5 g / L, the content of sodium gluconate is 1.8 g / L, the temperature of the plating bath is controlled in the range of 46°C, and the current density is controlled in the range of 13 A / dm 2 The passivation system: the content of Na2Cr2O7 is 21 g / L, the content of CrO3 is 5.5 g / L, the pH value is 3.6, and the temperature is 42.5°C. The rinsing system: the content of sodium citrate in the rinsing water is 33 mg / L, and the temperature is 46°C. According to the above production process flow, the high resistance easy forming low titanium electroplated tin plate with the regulation degree code T-3 is produced, the thickness of the finished product is 0.22 mm, the hardness value (HR30Tm) is 56, the r value is 1.8, the Δr value is 0.03, the adhesion of the coating after canning is 1 level, and the sulfur and acid resistance performance evaluation is qualified.

[0034] Example 5 The production process flow is: desulphurization → converter smelting → vacuum treatment → continuous casting → hot rolling → pickling and cold rolling → continuous annealing → tinning substrate → degreasing → electroplating tin → fluxing → quenching → passivation → rinsing → oiling and other processes. The designed tinning substrate chemical composition (by weight %) is C: 0.003, Si: 0.020, Mn: 0.55, Ti: 0.015, P: 0.006, S: 0.005, N: 0.002, Als: 0.010, Cu: 0.03, Ni: 0.04, Cr: 0.03, Mo: 0.02, and the rest is Fe and inevitable impurities. The hot rolled material is cold rolled by 5 passes with an accumulative reduction of 89.6% after pickling in an acid rolling mill, and the electroplated tin substrate is produced after degreasing and 745°C continuous annealing. The designed PSA electroplated tin insoluble anode plating system is: stannous ion (provided by stannous sulfate) content of 26 g / L, PSA (phenol sulfonic acid) content of 18 g / L, EN content of 6.5 g / L, ENSA content of 2.5 g / L, and sodium gluconate content of 1.7 g / L. The plating bath temperature is controlled in the range of 44°C, and the current density is controlled in the range of 17 A / dm 2 The passivation system is: Na2Cr2O7 content of 22.5 g / L, CrO3 content of 4.5 g / L, pH value of 3.7, and temperature of 42°C. The rinsing system is: sodium citrate content in the rinsing water of 37 mg / L, and temperature of 47°C. According to the above production process flow, the high resistance easy forming low titanium electroplated tin plate with the regulation system code T-3 is produced, the finished product thickness is 0.24 mm, the hardness value (HR30Tm) is 58, the r value is 1.9, the Δr value is -0.010, the coating adhesion after canning is 1 level, and the sulfur and acid resistance performance evaluation is qualified.

[0035] Comparative Example 1 The production process flow is: desulphurization → converter smelting → vacuum treatment → continuous casting → hot rolling → pickling and cold rolling → continuous annealing → tinning substrate → degreasing → electroplating tin → fluxing → quenching → passivation → rinsing → oiling and other processes. The designed chemical composition of the tinning substrate (in wt%) is C: 0.003, Si: 0.025, Mn: 0.25, Ti: 0.015, P: 0.006, S: 0.005, N: 0.002, Als: 0.010, Cu: 0.03, Ni: 0.04, Cr: 0.03, Mo: 0.02, and the rest is Fe and inevitable impurities. The hot rolled material is cold rolled by 5 passes with a cumulative reduction of 89.6% after pickling on an acid rolling mill, and the electroplated tinning substrate is produced after degreasing and continuous annealing at 745℃. The designed PSA electroplated tin insoluble anode plating system: stannous ion (provided by stannous sulfate) content is 26g / L, PSA (phenol sulfonic acid) content is 18g / L, EN content is 6.5g / L, ENSA content is 2.5g / L, sodium gluconate content is 1.7g / L, the plating bath temperature is controlled in the range of 44℃, the current density is controlled in the range of 17A / dm 2 The passivation system: Na2Cr2O7 content is 22.5g / L, CrO3 content is 4.5g / L, pH value is 3.7, temperature is 42℃. The rinsing system: sodium citrate content in the rinsing water is 37mg / L, temperature is 47℃. According to the above production process flow, the high resistance easy forming low titanium electroplated tin plate with the regulation code T-3 is produced, the finished product thickness is 0.24mm, the hardness value (HR30Tm) is 51 (not meeting the level of regulation code T-3), the r value is 1.85, the Δr value is 0.005, the coating adhesion after canning is 1 level, and the sulfur and acid resistance performance evaluation is qualified.

[0036] Comparative Example 2 The production process is: desulphurization → converter smelting → vacuum treatment → continuous casting → hot rolling → pickling and cold rolling → continuous annealing → tinning substrate → degreasing → electroplating tin → fluxing → quenching → passivation → rinsing → oiling, etc. The designed chemical composition of the tinning substrate (in wt%) is: C: 0.004, Si: 0.025, Mn: 0.58, Ti: 0.017, P: 0.007, S: 0.008, N: 0.003, Als: 0.015, Cu: 0.025, Ni: 0.03, Cr: 0.02, Mo: 0.03, and the rest is Fe and inevitable impurities. The hot rolled material is cold rolled by 5 passes with an accumulative reduction of 89.3% after pickling in an acid rolling unit, and the electroplated tinning substrate is produced after degreasing and continuous annealing at 735℃. The designed PSA electroplated tin insoluble anode plating system is: stannous ion (provided by stannous sulfate) content of 27 g / L, PSA (phenol sulfonic acid) content of 17 g / L, EN content of 6.0 g / L, ENSA content of 3.0 g / L, without adding sodium gluconate, the plating bath temperature is controlled in the range of 45℃, and the current density is controlled in the range of 16 A / dm 2 The passivation system is: Na2Cr2O7 content of 22.0 g / L, CrO3 content of 5.0 g / L, pH value of 3.5, and temperature of 42℃. The rinsing system is: sodium citrate content in the rinsing water of 36 mg / L, and temperature of 46℃. According to the above production process, the high resistance easy-forming low-titanium electroplated tin plate with the regulation degree code T-3 is produced, the thickness of the finished product is 0.23 mm, the hardness value (HR30Tm) is 57, the r value is 1.92, the Δr value is 0.012, the adhesion of the coating after canning is grade 3, and the sulfur and acid resistance performance evaluation is unqualified.

[0037] Comparative Example 3 The production process flow is: desulphurization → converter smelting → vacuum treatment → continuous casting → hot rolling → pickling and cold rolling → continuous annealing → tinning substrate → degreasing → electroplating tin → fluxing → quenching → passivation → rinsing → oiling and other processes. The designed tinning substrate chemical composition (by weight %) is C: 0.007, Si: 0.021, Mn: 0.63, Ti: 0.021, P: 0.006, S: 0.007, N: 0.003, Als: 0.020, Cu: 0.035, Ni: 0.04, Cr: 0.03, Mo: 0.02, and the rest is Fe and inevitable impurities. The hot rolled material is cold rolled by 5 passes after pickling in the pickling mill unit, with a cumulative reduction rate of 89.8%, and the electroplated tinning substrate is produced after degreasing and 730°C continuous annealing. The designed PSA electroplated tin insoluble anode plating system: stannous ion (stannous sulfate) content is 26 g / L, PSA (phenol sulfonic acid) content is 18 g / L, EN content is 5.5 g / L, ENSA content is 3.5 g / L, sodium gluconate content is 1.8 g / L, the plating bath temperature is controlled in the range of 46°C, and the current density is controlled in the range of 19 A / dm 2 The passivation system: Na2Cr2O7 content is 23.0 g / L, CrO3 content is 3.0 g / L, pH value is 4.3, and temperature is 43°C. The rinsing system: sodium citrate content in the rinsing water is 35 mg / L, and temperature is 47°C. According to the above production process flow, the high resistance easy forming low titanium electroplated tin plate with the regulation degree code T-3 is produced, the finished product thickness is 0.22 mm, the hardness value (HR30Tm) is 58, the r value is 1.95, the Δr value is 0.031, the coating adhesion after canning is 2 levels, and the sulfur and acid resistance performance evaluation is qualified.

[0038] Comparative Example 4 The production process is: desulphurization, converter smelting, vacuum treatment, continuous casting, hot rolling, pickling and cold rolling, continuous annealing, tinning base plate, degreasing, electroplating, tin, softening, quenching, passivation, rinsing, oiling and other processes. The designed chemical composition of the tinning base plate (in wt%) is C: 0.005, Si: 0.023, Mn: 0.66, Ti: 0.026, P: 0.005, S: 0.008, N: 0.004, Als: 0.025, Cu: 0.025, Ni: 0.03, Cr: 0.02, Mo: 0.03, and the rest is Fe and inevitable impurities. The hot rolled material is cold rolled by 5 passes with an accumulative reduction of 89.7% after pickling in an acid rolling mill, and the electroplated tinning base plate is produced after degreasing and continuous annealing at 750℃. The designed PSA electroplated tinning insoluble anode plating system is: stannous ion (provided by stannous sulfate) content is 28g / L, PSA (phenol sulfonic acid) content is 16g / L, EN content is 6.5g / L, ENSA content is 2.5g / L, and sodium gluconate content is 1.9g / L. The plating bath temperature is controlled in the range of 46℃, and the current density is controlled in the range of 19A / dm 2 The passivation system is: Na2Cr2O7 content is 22.0g / L, CrO3 content is 5.0g / L, pH value is 3.4, and temperature is 42.5℃. The rinsing system does not add sodium citrate in the rinsing water, and the temperature is 45℃. According to the above production process, the high resistance and easy forming low titanium electroplated tin plate with the regulation degree code T-3 is produced, the thickness of the finished product is 0.22mm, the hardness value (HR30Tm) is 59, the r value is 1.91, the Δr value is 0.028, the adhesion of the coating after canning is 2, and the sulfur and acid resistance performance evaluation is qualified.

Claims

1. An electroplated tin substrate, characterized by: The chemical composition of the electroplated tin substrate includes C: 0.001-0.025%, Si: ≤0.030%, Mn: 0.50-0.70%, Ti: 0.010-0.030%, P: ≤0.010%, S: ≤0.010%, N: ≤0.005%, Al: 0.005-0.040%, Cu: ≤0.06%, Ni: ≤0.04%, Cr: ≤0.06%, Mo: ≤0.05% by weight, and the rest is Fe and inevitable impurities.

2. The electro-tinning substrate of claim 1, wherein: The preparation process of the electroplated tin substrate includes desulfurization, converter smelting, vacuum treatment, continuous casting, hot rolling, pickling and cold rolling, continuous annealing in sequence; the hot rolled material is subjected to 4-6 passes of cold rolling by an acid rolling mill after pickling, with a cumulative reduction rate of 89.0±1.0%, and the electroplated tin substrate is produced after degreasing and continuous annealing at 740±15℃.

3. A process for the production of a high resistance, easily formable, low titanium electro-galvanised tinplate characterised in that: The electroplated tin substrate of claim 1 is subjected to the following processes in sequence: degreasing, electroplating tin, reflowing, quenching, passivation, rinsing and oiling; the electroplating tin process uses PSA electroplated tin insoluble anode tin plating solution, which includes stannous ions, PSA, EN, ENSA and sodium gluconate, wherein the content of stannous ions is 25-30g / L, the content of PSA is 15-20g / L, the content of EN is 5-7g / L, the content of ENSA is 2-4g / L, and the content of sodium gluconate is 1-2g / L.

4. The method of producing a high resistance, easily formable, low titanium electro-galvanised tinplate according to claim 1, characterised in that: The passivation solution in the passivation process includes Na2Cr2O7 and CrO3, wherein the content of Na2Cr2O7 is 20-23g / L, and the content of CrO3 is 4.0-6.0g / L.

5. The production method of the high-resistance, easily-shaped, low-titanium electro-galvanized tin plate according to claim 3 or 4, characterized in that: The plating solution temperature of the electroplating tin process is 45℃±3℃, and the current density is 10-20A / dm 2 .

6. The method of producing a high resistance, easily formable, low titanium electro-galvanised tinplate according to claim 4, characterised in that: The pH value of the passivation solution in the passivation process is 3.5±0.2, and the temperature is 42±1℃.

7. The production method of the high-resistance, easily-shaped, low-titanium electro-galvanized tin plate according to claim 3 or 4, characterized in that: Sodium citrate is added to the rinsing water in the rinsing process, and the content of sodium citrate is 30-40mg / L.

8. The production method of the high-resistance, easily formable, low-titanium electro-galvanized tin plate according to claim 7, characterized in that: The temperature of the rinsing water in the rinsing process is 45±3℃.