CN101487099A - Corrosion resistant steel plate for automobile fuel tank and manufacturing method thereof - Google Patents
Corrosion resistant steel plate for automobile fuel tank and manufacturing method thereof Download PDFInfo
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- CN101487099A CN101487099A CNA2009100738128A CN200910073812A CN101487099A CN 101487099 A CN101487099 A CN 101487099A CN A2009100738128 A CNA2009100738128 A CN A2009100738128A CN 200910073812 A CN200910073812 A CN 200910073812A CN 101487099 A CN101487099 A CN 101487099A
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Abstract
The invention relates to a corrosion resistance steel plate used for a tank of a car and a preparation method thereof, which comprises less than or equal to 0.03 percent of C, 0.10 percent to 1.00 percent of Si, 0.10 percent to 1.00 percent of Mn, 14.0 percent to 22.0 percent of Cr, less than or equal to 0.035 percent of P, less than or equal to 0.030 percent of N, less than or equal to 0.010 percent of S, less than or equal to 0.60 percent of Cu, 10 (C+N) to 0.80 percent (Nb/Ti is more than or equal to 2) of Ti+Nb and the balance of ferrite and inevitable impurities. The metallurgical structure of the steel plate is of ferrite structure, and the grain size ranges from 9 to 10 grades. The preparation method comprises the main steps of billet smelting, casting billet and hot rolling, hot coil annealing, pickling, cold rolling, annealing and pickling of finished products. The characteristics of each main step are as follows: the molten steel and scraps and chromium alloy are subjected to primary melting and refining treatment, and then poured into a casting billet. The tank made of the corrosion resistance steel plate has no need of coating or painting, and can be used directly, and the mechanical strength of the tank can meet the application requirements of the tank used by cars.
Description
Technical field
The present invention relates to a kind of corrosion resistant steel plate for automobile fuel tank and preparation method thereof.
Background technology
Present Domestic Automotive Industry high speed development, the material that automotive oil tank uses increases considerably, because automotive oil tank is directly exposed in the air and uses, automotive oil tank requires corrosion-resistant and enough physical strengths is arranged.Existing corrosion resistant steel plate for automobile fuel tank is the cold-rolled carbon steel long ternes, and the inside and outside all lead plating of fuel tank also need be painted because of lead plating rear fuel tank outside, so be unfavorable for environmental protection, often are subjected to environmental administration and near resident's reflection.Along with social progress, more and more stricter to the requirement of automobile emission.After adopt aluminum alloy materials again, though weight alleviates, cost improves, safety performance reduces.Because outside the truck fuel tank all is exposed to, the aluminum fuel tank is softer, and is unavoidable under the bad situation in road surface, and the stone collision of being splashed causes fuel tank to leak and accidents caused.Because of there being the people to steal oil plant in the society, the aluminum fuel tank is very easily punctured again, causes automobile to move, though so the aluminum fuel tank attractive in appearance, impracticable, consequent claim incident constantly takes place.
Summary of the invention
In order to overcome the above-mentioned deficiency of existing corrosion resistant steel plate for automobile fuel tank, solve the environmental issue of above-mentioned coated material, the invention provides a kind of corrosion-resistant stainless steel steel plate, the fuel tank that adopts this material to make does not need coating and paint, can directly use, and physical strength satisfies the service requirements of automotive oil tank, the invention provides a kind of preparation method of corrosion resistant steel plate for automobile fuel tank simultaneously.
Design of the present invention is when considering the rotproofing of tank internal surface, not only to take into account and dielectric compatibility, workability after also will considering to handle, be fabricated onto the timed interval and economy, the feature of environmental protection and physical strength between coming into operation, be undoubtedly more satisfactory selection so adopt anti-corrosion steel plate to make fuel tank.
Technical scheme of the present invention is the content that increases chromium in the steel, and chromium is to improve the corrosion proof useful alloy of material, and the high more effect of chromium content is good more; Lower carbon, nitrogen content have reduced the brittle transition temperature of material, have improved the mechanical property of material; Add an amount of niobium, titanium, suppressed the carbon of chromium, the formation of nitride, thereby improve the intergranular corrosion resistance performance of steel, improved the welding property of steel plate; The copper that adds trace improves the cold-forming property of material.Add corresponding art breading again, thereby become erosion resistance, processibility, toughness, the good automotive oil tank steel plate special of weldability.Material does not contain nickel, molybdenum simultaneously, and is with low cost, has the very strong market competitiveness.
The weight percent of the composition characteristics of corrosion resistant steel plate for automobile fuel tank of the present invention is:
C≤0.03% Si 0.10%~1.00% Mn 0.10%~1.00%
Cr 14.0%~22.0% P≤0.035% S≤0.010%
N≤0.030% Cu≤0.60% Ti+Nb 10(C+N)~0.80%
All the other are Fe and unavoidable impurities.
Through the corrosion resistant steel plate for automobile fuel tank after rolling, annealing back and the pickling, its unit elongation 〉=30%, metallographic structure is a ferritic structure, grain fineness number is the 9-10 level.Thickness is generally 0.8mm~2.0mm.
The weight percent of the preferred composition of corrosion resistant steel plate for automobile fuel tank of the present invention is:
C 0.008% Si 0.33% Mn 0.21% Cr 17.72%
P 0.011% S 0.003% Cu 0.23% N 0.011%
Ti+Nb 0.33%(Nb/Ti≥2)
All the other are Fe and unavoidable impurities.
This corrosion resistant steel plate for automobile fuel tank and preparation method thereof comprises the key step of next coming in order:
(1), smelts steel billet
After adopting molten steel and steel scrap and Chrome metal powder by AOD stove or K-OBM-S converter refining just, pass through VOD stove refining treatment again, pour into strand, the composition of strand (weight percent) is:
C≤0.03% Si 0.10%~1.00% Mn 0.10%~1.00%
Cr 14.0%~22.0% P≤0.035% S≤0.010%
N≤0.030% Cu≤0.60% Ti+Nb 10(C+N)~0.80%
All the other are Fe and unavoidable impurities for (Nb/Ti 〉=2).
(2), strand hot rolling
Strand is heated in sealed heating furnace, and slab heating temperature is 1160 ± 20 ℃, heat-up time 〉=200 minute.
Adopt control roughing temperature and finishing temperature technology, the rougher of hot strip mill temperature is controlled at 1010~1060 ℃, and final rolling temperature is controlled at 860~900 ℃, throws laminar cooling water after the hot rolling, and coiling temperature is controlled at 650~700 ℃.
(3), hot rolling annealing
Hot rolling adopts the on-line continuous annealing process, and annealing temperature is controlled at 960 ± 20 ℃, and annealing time was by control in 1~2 minute/millimeter.
(4), hot rolling pickling
Sulfuric acid and nitration mixture acid cleaning process are adopted in the coil of strip pickling, and be specific as follows:
H 2SO 4 | HNO 3+HF | |
Temperature | 85-90℃ | 35-50℃ |
Concentration | 250-300g/l | HNO 3:120-150g/l,HF:5-15g/l |
(5) cold rolling, annealing
Hot rolling after the pickling is carried out cold rolling, cold rolling draft 〉=50%, then cold-reduced sheet is annealed, annealing temperature is set at 880 ± 20 ℃, and annealing time was by control in 1~2 minute/millimeter.
(6) finished product acid-washing
The coil of strip finished product acid-washing adopts sodium sulfate electrolysis and nitration mixture acid cleaning process, and is specific as follows:
The sodium sulfate electrolysis | The nitration mixture pickling | |
Na 2SO 4 | HNO 3+HF | |
Temperature | 70-100℃ | ≤50℃ |
Concentration | 1.15-1.20g/cm 3 | HNO 3:80-150g/l,HF:5-25g/l |
Through the corrosion resistant steel plate for automobile fuel tank after rolling, annealing back and the pickling, its unit elongation 〉=30%, metallographic structure is a ferritic structure, grain fineness number is the 9-10 level.
The corrosion resistant steel plate for automobile fuel tank of preparation method's preparation of the present invention contains higher chromium, and chromium is to improve the corrosion proof useful alloy of material, and the high more effect of chromium content is good more; Lower carbon, nitrogen content have improved the mechanical property of material, have reduced the brittle transition temperature of material; Add an amount of niobium, titanium, suppressed the carbon of chromium, the formation of nitride, thereby improve the intergranular corrosion resistance performance of steel, improved the welding property of steel plate; The copper that adds trace improves the cold-forming property of material.Add corresponding art breading again, thereby become erosion resistance, processibility, toughness, the good automotive oil tank steel plate special of weldability, physical strength can satisfy the service requirements of automotive oil tank than all leaded cold-rolled carbon steel fuel tank height inside and outside existing.Simultaneously material does not contain nickel, molybdenum, with existing inside and outside all leaded cold-rolled carbon steel fuel tank compare, cost is suitable; Compare with the aluminium alloy fuel tank, with low cost.
Embodiment
Describe the embodiment of this corrosion resistant steel plate for automobile fuel tank and production method thereof in detail below in conjunction with embodiment, but the embodiment of this corrosion resistant steel plate for automobile fuel tank and production method thereof is not limited to following embodiment.
Steel plate embodiment one
The steel plate thickness that the automotive oil tank of present embodiment is used is 1.5mm, width 1220mm, and its chemical ingredients (weight percent) is:
C 0.011% Si 0.31% Mn 0.16% Cr 20.66%
P 0.018% S 0.003% Cu 0.34% N 0.012%
Ti 0.12% Nb 0.27%
All the other are Fe and unavoidable impurities.
Through the corrosion resistant steel plate for automobile fuel tank after rolling, annealing back and the pickling, its unit elongation 38%, metallographic structure is a ferritic structure, grain fineness number is 9 grades.
Steel plate embodiment two
The steel plate thickness that the automotive oil tank of present embodiment is used is 1.2mm, width 1220mm, and its chemical ingredients (weight percent) is:
C 0.008% Si 0.33% Mn 0.21% Cr 17.72%
P 0.011% S 0.003% Cu 0.23% N 0.011%
Ti 0.10% Nb 0.23%
All the other are Fe and unavoidable impurities.
Through the corrosion resistant steel plate for automobile fuel tank after rolling, annealing back and the pickling, its unit elongation 40%, metallographic structure is a ferritic structure, grain fineness number is 10 grades.
Steel plate embodiment three
The steel plate thickness that the automotive oil tank of present embodiment is used is 1.0mm, width 1220mm, and its chemical ingredients (weight percent) is:
C 0.010% Si 0.32% Mn 0.22% Cr 15.24%
P 0.014% S 0.002% Cu 0.21% N 0.009%
Ti 0.09% Nb 0.20%
All the other are Fe and unavoidable impurities.
Through the corrosion resistant steel plate for automobile fuel tank after rolling, annealing back and the pickling, its unit elongation 43%, metallographic structure is a ferritic structure, grain fineness number is 10 grades.
Preparation method embodiment one
What present embodiment prepared is the steel plate of steel plate embodiment one, and the preparation method is following key step successively;
(1), smelts steel billet
Smelt with electric furnace → AOD stove or converter → furnaceman's VOD skill or other technology and to be cast into steel billet, the chemical ingredients of steel billet (weight percent) is:
C 0.011% Si 0.31% M n0.16% Cr 20.66%
P 0.018% S 0.003% Cu 0.34% N 0.012%
Ti 0.12% Nb 0.27%
All the other are Fe and unavoidable impurities.
(2), strand hot rolling
Strand is heated in sealed heating furnace, and slab heating temperature is 1155 ℃, 211 minutes heat-up times.
Adopt control roughing temperature and finishing temperature technology, the rougher of hot strip mill temperature is controlled at 1015 ℃, and the hot continuous rolling final rolling temperature is controlled at 885 ℃, throws laminar cooling water after the hot rolling, and coiling temperature is controlled at 675 ℃.
(3), hot rolling annealing
Hot rolling adopts the on-line continuous annealing process, and annealing temperature is controlled at 970 ℃, annealing time 3.6 minutes.
(4), hot rolling pickling
The coil of strip acid cleaning process adopts sulfuric acid and nitration mixture acid cleaning process, and is specific as follows:
H 2SO 4 | HNO 3+HF | |
Temperature | 87.1℃ | 42℃ |
Concentration | 285g/l | HNO 3:122g/l,HF:9g/l |
(5), cold rolling, annealing
Hot rolling after the pickling is carried out cold rolling, then cold-reduced sheet is annealed, annealing temperature is set at 895 ℃, annealing time 1.9 minutes.
(6), finished product acid-washing
Sodium sulfate electrolysis of coil of strip finished product acid-washing process using and nitration mixture acid cleaning process, specific as follows:
Na 2SO 4 | HNO 3+HF | |
Temperature | 85℃ | 43℃ |
Concentration | 1.17g/cm 3 | HNO 3:110g/l,HF:12g/l |
Through the corrosion resistant steel plate for automobile fuel tank after rolling, annealing back and the pickling, its unit elongation 38%, metallographic structure is a ferritic structure, grain fineness number is 9 grades.
Preparation method embodiment two
What present embodiment prepared is the steel plate of steel plate embodiment two
(1), smelts steel billet
Smelt with electric furnace → AOD stove or converter → furnaceman's VOD skill or other technology and to be cast into steel billet, the chemical ingredients of steel billet (weight percent) is:
C 0.008% Si 0.33% Mn 0.21% Cr 17.72%
P 0.011% S 0.003% Cu 0.23% N 0.011%
Ti 0.10% Nb 0.23%
All the other are Fe and unavoidable impurities.
(2) strand hot rolling, the annealing of (three) hot rolling, the pickling of (four) hot rolling, (five) are cold rolling, the step method of annealing and (six) finished product acid-washing and preparation method and embodiment one identical.
Through the corrosion resistant steel plate for automobile fuel tank after rolling, annealing back and the pickling, its unit elongation 40%, metallographic structure is a ferritic structure, grain fineness number is 10 grades.
Preparation method embodiment three
What present embodiment prepared is the steel plate of steel plate embodiment three
(1), smelts steel billet
Smelt with electric furnace → AOD stove or converter → furnaceman's VOD skill or other technology and to be cast into steel billet, the chemical ingredients of steel billet (weight percent) is: C 0.010% Si 0.32%Mn 0.22% Cr 15.24% P 0.014% S 0.002%Cu 0.21% N 0.009% Ti 0.09% Nb 0.20%
All the other are Fe and unavoidable impurities.
(2) strand hot rolling, the annealing of (three) hot rolling, the pickling of (four) hot rolling, (five) are cold rolling, the step method of annealing and (six) finished product acid-washing and preparation method and embodiment one identical.
Through the corrosion resistant steel plate for automobile fuel tank after rolling, annealing back and the pickling, its unit elongation 43%, metallographic structure is a ferritic structure, grain fineness number is 10 grades.
Below with three embodiment of anti-corrosion steel plate of the present invention, compare with mechanical property, the erosion resistance of coating carbon steel.The mechanical property contrast sees Table 1.
Material | Yield strength R P0.2(MPa) | Tensile strength R P0.2(MPa) | Unit elongation A (%) |
Embodiment one | 350 | 505 | 38 |
Embodiment two | 310 | 490 | 40 |
Embodiment three | 280 | 480 | 43 |
The coating carbon steel | 200 | 340 | 40 |
See Table 2 with the corrosion resistance nature contrast of coating carbon steel,, adopt salt spray corrosion test NaCl solution, solubility 50g/l, spraying continuously, 35 ℃ of temperature according to GB10125.
Material | Begin to occur etching time |
Embodiment one | 200 hours |
Embodiment two | 148 hours |
Embodiment three | 121 hours |
The coating carbon steel | 110 hours |
Claims (6)
1, a kind of corrosion resistant steel plate for automobile fuel tank, the weight percent of its composition characteristics is:
C≤0.03% Si 0.10%~1.00% Mn 0.10%~1.00%
Cr 14.0%~22.0% P≤0.035% S≤0.010%
N≤0.030% Cu≤0.60%
Ti+Nb 10(C+N)~0.80%(Nb/Ti≥2)
All the other are Fe and unavoidable impurities.
2, a kind of corrosion resistant steel plate for automobile fuel tank, the weight percent of its composition characteristics is:
C 0.008% Si 0.33% Mn 0.21% Cr 17.72%
P 0.011% S 0.003% Cu 0.23% N 0.011%
Ti+Nb 0.33%(Nb/Ti≥2)
All the other are Fe and unavoidable impurities.
3, corrosion resistant steel plate for automobile fuel tank according to claim 1 and 2 is characterized in that: through after rolling, annealing back and the pickling, and its unit elongation 〉=30%, metallographic structure is a ferritic structure, grain fineness number is the 9-10 level.
4, a kind of preparation method of corrosion resistant steel plate for automobile fuel tank, it comprises successively smelting steel billet, strand hot rolling, hot rolling annealing, pickling, cold rolling, annealing and finished product acid-washing key step, being characterized as of each key step:
After adopting molten steel and steel scrap and Chrome metal powder by AOD stove or K-OBM-S converter refining just, pass through VOD stove refining treatment again, pour into strand, the weight percent of the composition of strand is:
C≤0.03% Si 0.10%~1.00% Mn 0.10%~1.00%
Cr 14.0%~22.0% P≤0.035% S≤0.010%
N≤0.030% Cu≤0.60% Ti+Nb 10(C+N)~0.80%
All the other are Fe and unavoidable impurities for (Nb/Ti 〉=2);
Anneal at step (three) hot rolling
Hot rolling adopts the on-line continuous annealing process, and annealing temperature is controlled at 960 ± 20 ℃, and annealing time was by control in 1~2 minute/millimeter;
Cold rolling through step (five), annealing after, the unit elongation of steel plate 〉=30%, metallographic structure is a ferritic structure, grain fineness number is the 9-10 level.
5, the preparation method of corrosion resistant steel plate for automobile fuel tank according to claim 4, when it is characterized in that finished product acid-washing, the coil of strip finished product acid-washing adopts sodium sulfate electrolysis and nitration mixture acid cleaning process, and is specific as follows:
6,, it is characterized in that the weight percent of the composition of strand is when smelting steel billet according to the preparation method of claim 4 or 5 described corrosion resistant steel plate for automobile fuel tank:
C 0.008% Si 0.33% Mn 0.21% Cr 17.72%
P 0.011% S 0.003% Cu 0.23% N 0.011%
Ti+Nb 0.33%(Nb/Ti≥2)
All the other are Fe and unavoidable impurities.
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
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CN102312166A (en) * | 2011-07-01 | 2012-01-11 | 山西太钢不锈钢股份有限公司 | Stanniferous ferrite stainless steel and smelting method therefor |
CN102312165A (en) * | 2011-07-01 | 2012-01-11 | 山西太钢不锈钢股份有限公司 | Stainless steel plate for fuel tank of automobile and manufacturing method thereof |
CN105586600A (en) * | 2016-03-16 | 2016-05-18 | 甘肃酒钢集团宏兴钢铁股份有限公司 | Duplex stainless steel cold rolling annealing and pickling process |
CN112501493A (en) * | 2020-07-14 | 2021-03-16 | 福建青拓特钢技术研究有限公司 | Nickel-saving high-nitrogen austenitic stainless steel with excellent pitting corrosion resistance and sulfuric acid corrosion resistance and manufacturing method thereof |
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2009
- 2009-02-20 CN CNA2009100738128A patent/CN101487099A/en active Pending
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102312166A (en) * | 2011-07-01 | 2012-01-11 | 山西太钢不锈钢股份有限公司 | Stanniferous ferrite stainless steel and smelting method therefor |
CN102312165A (en) * | 2011-07-01 | 2012-01-11 | 山西太钢不锈钢股份有限公司 | Stainless steel plate for fuel tank of automobile and manufacturing method thereof |
CN105586600A (en) * | 2016-03-16 | 2016-05-18 | 甘肃酒钢集团宏兴钢铁股份有限公司 | Duplex stainless steel cold rolling annealing and pickling process |
CN105586600B (en) * | 2016-03-16 | 2018-06-29 | 甘肃酒钢集团宏兴钢铁股份有限公司 | A kind of cold rolled annealed acid cleaning process of two phase stainless steel |
CN112501493A (en) * | 2020-07-14 | 2021-03-16 | 福建青拓特钢技术研究有限公司 | Nickel-saving high-nitrogen austenitic stainless steel with excellent pitting corrosion resistance and sulfuric acid corrosion resistance and manufacturing method thereof |
CN112501493B (en) * | 2020-07-14 | 2022-01-18 | 福建青拓特钢技术研究有限公司 | Nickel-saving high-nitrogen austenitic stainless steel with excellent pitting corrosion resistance and sulfuric acid corrosion resistance and manufacturing method thereof |
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