双相高强度冷连轧钢板及钢带（Dual phase high strength steel sheet and strip cold rolling）

1、双相高强度冷连轧钢板及钢带（Dual phase high strength steel sheet and strip cold rolling）Baoshan Iron Steel Co enterprise standardDual phase high strength cold rolled steel sheet and strip(Q/BQB 418-2009 instead of Q/BQB 418-2003)1 rangeThis standard specifies the terms and definitions, classification and codes, d

2、imensions, shapes, weights, technical requirements, inspection and testing, packaging, marking and inspection documents of tandem cold rolled steel and strip steel.This standard is applicable to the dual phase high strength cold rolled steel plate and steel strip produced by Baoshan Iron Steel Co, w

3、hose thickness is from 0.50mm to 2.3mm (hereinafter referred to as steel plate and steel strip).2 normative reference documentsThe terms in the following documents are referenced by this standard and become the provisions of this standard. Fordated documents, subsequent amendments (excluding correct

4、ions) or revisions do not apply to this standard, however, encourage the latest version of the parties to agreements based on this standard using these files. Any undated reference document whose latest edition is applicable to this standard.Allowable deviation of chemical composition of finished pr

5、oduct of GB/T 222-2006 steelGB/T 223 methods for chemical analysis of iron, steel and alloyTest method for room temperature tensile testing of GB/T 228-2002 metal materialsGB/T 232-1999 bending test method for metallic materialsMechanical properties test, sampling location and specimen preparation o

6、f GB/T 2975-1998 steel and steel productsGB/T 4336-2002 carbon and low alloy steel spark source atomic emission spectrometric analysis (conventional method)Determination of tensile strain hardening index (n value) of GB/T 5028-2008 metallic materials, plates and stripsGB/T 8170-2008 said the roundin

7、g rules and limit values and judgmentMethods of sampling and preparation of samples for determination of chemical composition of GB/T 20066-2006 steel and ironGB/T 20123-2006. Determination of total carbon and sulfur content of steel - high frequency induction furnace infrared absorption method afte

8、r combustion (routine method)GB/T 20125-2006 low alloy steels - Determination of multi-element content - Inductively Coupled Plasma Atomic Emission SpectrometryGB/T 20126-2006 unalloyed steels - Determination of low carbon content - second part: induction furnace (pre heating), internal combustion,

9、infrared absorption methodQ/BQB400 packaging, marking and inspection documents for cold rolling productsQ/BQB401 cold rolled steel plate and strip size, shape, weight and allowable deviation3 terms and definitions3.1 dual phase steel dual, phase, steels (DP)The microstructure of the steel is ferrite

10、 and martensite, and the martensite structure is dispersed on the base of ferrite on the island. Dual phase steel has no aging, low strength ratio and higher work hardening performance. Under the same yield strength level, higher strength and lower alloy have higher strength, and it is one of the pr

11、eferred materials for structural parts.4 Classification and designation4.1 the steel plate and steel strip shall be classified according to the provisions of Table 1 according to their use.4.2 steel plate and steel strip shall be classified according to surface quality and shall comply with the prov

12、isions of table 2.Table 1Brand useHC250/450DP structural partsHC300/500DP structural parts, reinforcementHC280/590DPHC340/590DPB340/590DPHC550/690DP reinforced parts, anti-collision partsHC420/780DPHC500/780DPB400/780DPHC550/980DPHC820/1180DPTable 2Class codeA higher finishing surface, FBAdvanced fi

13、nishing surface FCUltra high finishing surface FD5 information required for ordering5.1 when ordering, the user shall provide the following information:A) product name (steel plate or strip);(b) the standard number of this product;C) brand;(d) product specification and size, unevenness accuracy;E) e

14、dge states;(f) surface quality grade;G) packing methods;H) use;I) other.5.2 if the contract does not specify the size and roughness accuracy, surface quality level, edge and packing, the standard products according to the average size and roughness of FB grade precision and surface quality of the st

15、rip edge cutting and trimming plate supply, packing and packaging supplier provided by.6 size, shape, weight and allowable deviationThe size, shape, weight and allowable deviation of the steel plate and strip shall comply with the provisions of Q/BQB 401.7 technical requirements7.1 chemical composit

16、ionThe chemical composition (melting analysis) of 7.1.1 steel shall conform to the provisions of table 3.The allowable deviation of the chemical composition of 7.1.2 steel plate and steel strip shall comply with the provisions of GB/T 222.Table 3Chemical composition a (smelting analysis)%CNot greate

17、r than SiNot greater than MnNot greater than PNot greater than SNot greater than AltNot less thanHC250/450DP, 0.15, 0.6, 2.5, 0.040, 0.015, 0.010HC300/500DPHC280/590DPHC340/590DPB340/590DP, 0.18, 0.8, 2.2, 0.035, 0.030, 0.020HC550/690DP, 0.18, 0.6, 2.5, 0.040, 0.015, 0.010HC420/780DPHC500/780DPB400/

18、780DP, 0.20, 0.8, 2.5, 0.035, 0.030, 0.020HC550/980DP, 0.23, 0.6, 3, 0.040, 0.015, 0.010HC820/1180DP, 0.23, 0.6, 3, 0.040, 0.015, 0.010A allows you to add other alloying elements, but Ni+Cr+Mo = 1.5%, Cu = 0.20%.7.2 steel plate and steel used in oxygen converter smelting.7.3 delivery status7.3.1 ste

19、el and strip cold rolled, annealed and leveled for delivery.7.3.2 steel plates and steel belts are usually supplied by oil, and the coating shall be removed with alkaline solution. In the usual packing, transportation, handling and storage conditions, the supplier shall ensure that the steel and ste

20、el strip surfaces are not rusty within 6 months from the date of completion of the manufacture. In accordance with the requirements of the buyer, the agreement may be made by both the supplier and the buyer, and may not be supplied by oil as specified in the contract.7.4 mechanical propertiesThe mec

21、hanical properties of steel plate and steel strip shall meet the requirements of Table 4 and table 5 respectively.Table 4Brand tensile test a, B, C, N90Not less thanYield strengthRP0.2MPa tensile strengthRmMpaNot less than the elongationA80mm%Not less thanHC250/450DP 25032045027 0.16HC300/500DP 3003

22、9050023 0.15HC280/590DP 28038059022 0.14HC340/590DP 34044059020 0.14HC550/690DP 550 660690 12HC420/780DP 420 14 - 550780HC500/780DP 500 10 - 650780hc550 / 980dp 550 730 980 7hc820 / 1180dp 820 1130 1180 3一个无明显屈服时采用Rp0.2，否则采用REL。B试样为GB/T 228中的P6试样，试样方向为横向。C当产品公称厚度大于0.50mm，但小于等于0.70mm时，断后伸长率允许下降2%；当产品

23、公称厚度不大于0.50mm时，断后伸长率允许下降4%。表5牌号拉伸试验180弯曲试验C弯心直径不小于（a试样厚度）屈服强度A、BMPA抗拉强度MPa不小于断后伸长率B（L0 = 50mm，B = 25mm）%不小于公称厚度毫米11.6 1.6 1b340 / 590dp 340 500 590 16 18 20 0.5a400 / 780dp 400 590 780 14 16 1.0a一个当屈服现象不明显时采用Rp0.2，否则采用REL。B试样为GB/T 228中的P14试样。试样方向为横向。C弯曲试验规定值适用于横向试样，弯曲试样宽度B35mm。仲裁试验时试样宽度为35mm。供方如能保证，

24、可不进行弯曲试验。7.5表面质量7.5.1钢板及钢带表面不得有结疤、裂纹、夹杂等对使用有害的缺陷，钢板及钢带不得有分层。7.5.2钢板及钢带各表面质量级别的特征应符合表6的规定。表6级别代号特征较高级的精整表面FB表面允许有少量不影响成型性及涂、镀附着力的缺陷，如轻微的划伤、压痕、麻点、辊印及氧化色斑等。高级的精整表面FC产品二面中较好的一面无肉眼可见的明显缺欠，另一面必须至少达到FB的要求。超高级的精整表面FD产品二面中较好的一面不应有影响涂漆后的外观质量或电镀后的外观质量的缺陷，另一面至少应达到FB的要求。7.5.3对于钢带，由于没有机会切除带缺陷部分，因此钢带允许带缺陷交货，但有缺陷的部

25、分不得超过每卷总长度的6%。8检验和试验8.1钢板及钢带的外观用肉眼检查。8.2钢板及钢带的尺寸、外形应用合适的测量工具测量。8.3 N值是在10%20%应变范围内计算得到的，均匀延伸小于20%时，计算的应变范围为10%至均匀延伸结束；当均匀延伸小于10%时，计算的应变范围为5%至均匀延伸结束。8.4钢板及钢带应按批验收，每个检验批应由不大于30吨的同牌号、同规格、同加工状态的钢板及钢带组成，对于卷重大于30吨的钢带，可以每卷作为一个检验批。8.5每批钢板及钢带的检验项目、试样数量、取样方法、试验方法应符合表7的规定。表7检验项目试样数量（个）取样方法试验方法化学分析1 /炉GB/T 2006

26、6 GB/T 223、GB/T 4336 GB/T 20123、GB/T 20125, GB/T 20126Tensile test 1/ batch GB/T 2975 GB/T 228Strain hardening exponent (n) 1/ batch GB/T 5028Bend test 1/ batch GB/T 2328.6 for the tensile test, bending test and N test, if a certain test result does not meet the standard requirements, then from the

27、same batch of twice a number of samples to carry out the re examination of the unqualified project. The reinspection result (including all the indexes required by the project test) is qualified and the whole batch is qualified. The reinspection result (including all the indexes required by the test

28、of the project), even if one of the indexes fails, the reinspection shall be disqualified. If the re examination fails, the test has been done, and the test results are not acceptable to a single piece, but the batch of materials not to be tested in a single piece can be re submitted by the test and

29、 acceptance.9 packing, marking and inspection documentsThe packing, marking and inspection documents of steel plate and steel strip shall comply with the provisions of Q/BQB 400. If the buyer has special requirements for the packing, it shall be noted in the contract.10 rounding rulesRounding rules

30、should be consistent with the provisions of GB/T 8170.11 grade approximate controlAn approximate comparison of the standard brand with the standard brand at home and abroad is given in Appendix A.Appendix A(informative appendix)An approximate comparison between the standard brand and the standard br

31、and at home and abroadTable A.1Q/BQB418-2009 Q/BQB418-2003 prEN10338:2007 SAEJ2340-1999 GMW3399-2008 SAEJ2745-2007HC250/450DP - HCT450X - CR450T/250Y-DP DP 440T/250YHC300/500DP - HCT500X 500, DL, CR490T/290Y-DP, DP, 490T/290YHC280/590DP - 600, DL1, CR590T/280Y-DP -HC340/590DPB340/590DP B340/590DP HCT600X 600 DL2 CR590T/340Y-DP DP 590T/340YHC550/690DP - 600, DH, CR690T/550Y-DP, DP, 690T/550YHC420/780DPB400/780DP B400/780D