CN115341141A - 一种低屈强比耐候桥梁钢及制备方法 - Google Patents
一种低屈强比耐候桥梁钢及制备方法 Download PDFInfo
- Publication number
- CN115341141A CN115341141A CN202210868018.8A CN202210868018A CN115341141A CN 115341141 A CN115341141 A CN 115341141A CN 202210868018 A CN202210868018 A CN 202210868018A CN 115341141 A CN115341141 A CN 115341141A
- Authority
- CN
- China
- Prior art keywords
- temperature
- weather
- yield ratio
- percent
- steel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 87
- 239000010959 steel Substances 0.000 title claims abstract description 87
- 238000002360 preparation method Methods 0.000 title claims abstract description 11
- 238000001816 cooling Methods 0.000 claims abstract description 44
- 238000005096 rolling process Methods 0.000 claims abstract description 41
- 238000005496 tempering Methods 0.000 claims abstract description 24
- 239000012535 impurity Substances 0.000 claims abstract description 11
- 229910052720 vanadium Inorganic materials 0.000 claims abstract description 11
- 239000000126 substance Substances 0.000 claims abstract description 7
- 238000009749 continuous casting Methods 0.000 claims description 21
- 238000000034 method Methods 0.000 claims description 21
- 238000001953 recrystallisation Methods 0.000 claims description 14
- 229910052802 copper Inorganic materials 0.000 claims description 8
- 238000010438 heat treatment Methods 0.000 claims description 8
- 238000002791 soaking Methods 0.000 claims description 8
- 229910001563 bainite Inorganic materials 0.000 claims description 7
- 229910052759 nickel Inorganic materials 0.000 claims description 6
- 238000003723 Smelting Methods 0.000 claims description 2
- 229910052804 chromium Inorganic materials 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 abstract description 7
- 238000013461 design Methods 0.000 abstract description 6
- 238000005266 casting Methods 0.000 description 8
- 230000007797 corrosion Effects 0.000 description 8
- 238000005260 corrosion Methods 0.000 description 8
- 239000000047 product Substances 0.000 description 8
- 239000010949 copper Substances 0.000 description 7
- 239000000463 material Substances 0.000 description 5
- 239000006104 solid solution Substances 0.000 description 5
- 238000005728 strengthening Methods 0.000 description 5
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- 229910052791 calcium Inorganic materials 0.000 description 4
- 239000011575 calcium Substances 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 4
- 239000012467 final product Substances 0.000 description 4
- 239000002994 raw material Substances 0.000 description 4
- 239000011651 chromium Substances 0.000 description 3
- 239000011572 manganese Substances 0.000 description 3
- 239000010936 titanium Substances 0.000 description 3
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 229910001567 cementite Inorganic materials 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- KSOKAHYVTMZFBJ-UHFFFAOYSA-N iron;methane Chemical compound C.[Fe].[Fe].[Fe] KSOKAHYVTMZFBJ-UHFFFAOYSA-N 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 238000004321 preservation Methods 0.000 description 2
- 238000007670 refining Methods 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- 229910000746 Structural steel Inorganic materials 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000005098 hot rolling Methods 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000002040 relaxant effect Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000009628 steelmaking Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 238000000844 transformation Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/46—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting
- B21B1/463—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting in a continuous process, i.e. the cast not being cut before rolling
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/74—Temperature control, e.g. by cooling or heating the rolls or the product
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0226—Hot rolling
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0236—Cold rolling
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/42—Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/44—Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/46—Ferrous alloys, e.g. steel alloys containing chromium with nickel with vanadium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/48—Ferrous alloys, e.g. steel alloys containing chromium with nickel with niobium or tantalum
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/50—Ferrous alloys, e.g. steel alloys containing chromium with nickel with titanium or zirconium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/58—Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/002—Bainite
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Steel (AREA)
Abstract
本发明公开了一种低屈强比耐候桥梁钢及制备方法,涉及钢铁生产技术领域,其化学成分及质量百分比如下:C:0.06%~0.09%、Si:0.15%~0.30%、Mn:1.51%~1.65%、P:0.009%~0.015%、S≤0.002%、Nb:0.020%~0.050%、Ti:0.010%~0.020%、V:0.010%~0.030%、Cu:0.30%~0.40%、Ni:0.30%~0.45%、Cr:0.45%~0.60%、Mo:0.16%~0.25%、Alt:0.02%~0.04%,余量为Fe及不可避免的夹杂。通过科学的成分设计及相匹配的控轧控冷+回火的制造方法,使得该耐候桥梁钢兼具低屈强比、高低温韧性和高延展性的特点。
Description
技术领域
本发明涉及钢铁生产技术领域,特别是涉及一种低屈强比耐候桥梁钢及制备方法。
背景技术
随着大型钢结构桥梁向大跨度、重载荷、全焊接结构方向发展,对桥梁结构的安全可靠性要求越来越严格。这对设计者提出了更高的要求,同时也对钢板质量提出了更高的标准,即不仅要求钢板具有高强度以满足结构轻量化要求,而且还应具有优良的塑性、低温韧性、焊接性、耐腐蚀性能等,以满足桥梁跨径更大、荷载更重的工况条件。因此,高强高韧高塑高耐候桥梁钢的应用,可以降低桥梁结构自重,降低桥梁工程设计、制造、施工难度等,同时可以提高使用寿命。
但是,随着钢的强度提高,钢的屈强比一般也会升高,甚至可以达到0.93以上。由于屈强比很高,一旦构件发生过载,如在地震等条件下,将迅速达到钢种极限强度而导致事故的发生。因此,较高的屈强比限制了高强度结构钢在桥梁工程上的应用。地震的频发和其造成的灾难性后果,引起了国外对桥梁抗震性的高度关注,并在一些结构设计规范中作了相关规定。低屈强比、高强、高韧、高塑、高耐候桥梁钢是桥梁建设的发展趋势。
专利号为CN108486466B的《一种屈服强度550MPa级高韧性耐候钢板及其制备方法》公开了一种屈服强度550MPa级高韧性耐候钢板的制备方法,该产品是热连卷,厚度薄、屈强比高,无法适用于大跨度、重载荷的现代桥梁制造用钢需求。
发明内容
本发明针对上述技术问题,克服现有技术的缺点,提供一种低屈强比耐候桥梁钢,其化学成分及质量百分比如下:C:0.06%~0.09%、Si:0.15%~0.30%、Mn:1.51%~1.65%、P:0.009%~0.015%、S≤0.002%、Nb:0.020%~0.050%、Ti:0.010%~0.020%、V:0.010%~0.030%、Cu:0.30%~0.40%、Ni:0.30%~0.45%、Cr:0.45%~0.60%、Mo:0.16%~0.25%、Alt:0.02%~0.04%,余量为Fe及不可避免的夹杂。
本发明进一步限定的技术方案是:
前所述的一种低屈强比耐候桥梁钢,其化学成分及质量百分比如下:C:0.06%~0.07%、Si:0.20%~0.30%、Mn:1.56%~1.65%、P:0.011%~0.015%、S≤0.002%、Nb:0.020%~0.040%、Ti:0.010%~0.020%、V:0.010%~0.030%、Cu:0.32%~0.36%、Ni:0.35%~0.45%、Cr:0.45%~0.60%、Mo:0.16%~0.20%、Alt:0.02%~0.04%,余量为Fe及不可避免的夹杂。
前所述的一种低屈强比耐候桥梁钢,其化学成分及质量百分比如下:C:0.07%~0.09%、Si:0.17%~0.20%、Mn:1.54%~1.59%、P:0.009%~0.015%、S≤0.002%、Nb:0.030%~0.040%、Ti:0.010%~0.020%、V:0.015%~0.025%、Cu:0.30%~0.35%、Ni:0.30%~0.40%、Cr:0.45%~0.55%、Mo:0.20%~0.25%、Alt:0.02%~0.04%,余量为Fe及不可避免的夹杂。
本发明的另一目的在于提供一种低屈强比耐候桥梁钢制备方法,包括冶炼、连铸、均热、轧制、弛豫、冷却以及离线回火:
采用的连铸坯厚度为150~320mm,连铸工序的连铸坯堆冷24h以上;连铸坯在均热工序中加热至中心温度为1130~1230℃,温度均匀性小于20℃,加热时间≥连铸坯厚度×1min/mm;
轧制工序是对除鳞后的连铸坯进行再结晶区轧制和未再结晶区轧制,再结晶区轧制的累积变形量为连铸坯厚度的50%以上;
中间坯待温780~990℃,待温厚度为2.0~4.0倍的成品厚度,到温后进行未再结晶区轧制,终轧温度控制在770~830℃;
弛豫工序中,弛豫至始冷温度为730℃~760℃;
冷却工序是自始冷温度进行层流冷却,返红温度控制在400~600℃,随后空冷至室温;
离线回火工序中,回火温度在500~600℃,并在此温度下保温20~40min,且保温时间与成品厚度成正比,随后自然冷却至室温。
前所述的一种低屈强比耐候桥梁钢制备方法,连铸坯的厚度增大,堆冷的时间随之增大,对于320mm的连铸坯,堆冷时间在48h以上。
前所述的一种低屈强比耐候桥梁钢制备方法,钢板厚度8~80mm。
前所述的一种低屈强比耐候桥梁钢制备方法,钢板屈服强度578MPa以上,抗拉强度698MPa以上,屈强比≤0.85,-40℃Akv在188J以上,延伸率≥20%;耐大气腐蚀性指数I≥6.5,I=I=26.01(%Cu)+3.88(%Ni)+1.20(%Cr)+1.49(%Si)+17.28(%P)-7.29(%Cu)(%Ni)-9.10(%Ni)(%P)-33.39(%Cu)2。
前所述的一种低屈强比耐候桥梁钢制备方法,钢板金相组织为回火贝氏体。
本发明的有益效果是:
(1)本发明通过科学的成分设计及相匹配的控轧控冷+回火的制造方法,使得该耐候桥梁钢兼具低屈强比、高低温韧性和高延展性的特点;
(2)本发明中以回火贝氏体为主的组织类型实现了低屈强比和高低温韧性和高延伸性,各成分及含量的说明如下:
C是钢中不可缺少的提高钢材强度及硬度的元素,对钢组织影响显著,C溶入基体形成间隙固溶体,起到固溶强化的作用,显著增加基体的强度;随着碳含量的增加,钢的抗拉强度和屈服极限会提高而延伸率、缺口冲击韧性则下降;当钢材中C含量较高时易加剧产生冷裂纹的,因此,本发明采用超低碳设计,少量的C在钢中形成微合金元素碳化物,起到第二相强化和细化晶粒作用,本发明C百分含量设定为0.06%~0.09%;
Mn是钢中一种主要元素,锰元素可以提高材料强度,虽然提高C含量或Cr也可提高强度,但碳元素过多影响成型性及焊接线,而Cr元素价格太高且储量有限,不利于降低成本,Mn元素在钢中还是防止热脆性的主要元素,综合考虑Mn的作用,本发明Mn百分含量设定为1.51%~1.65%;
Si元素在钢中主要以很强的固溶强化形式提高钢的强度,也是炼钢脱氧的必要元素,可以提高耐大气腐蚀性能,但明显降低钢的塑性和韧性且显著降低钢的表面涂镀性能,因此,综合考虑强度、韧性、塑性等因素,本发明Si百分含量设定为0.15%~0.30%;
P促进锈层非晶态转变,一般而言,Cu、P复合具有最优的耐候效果,是比较经济的耐蚀元素,考虑到P导致低温脆性和裂纹敏感性,在重要焊接结构用耐候钢中,一般限制P的含量,本发明P百分含量控制窄区间为0.009%~0.015%;
Cu元素在钢中主要起到固溶强化作用,适量的铜可提高强度而不降低韧性,也可提高钢的耐蚀性,本发明Cu百分含量为0.30%~0.40%;
Ni是唯一能够改善低温冲击韧性(NDT、CTOD、DWTT等)的元素,也能有效的防止在连铸和热轧期间发生铜诱发的表面开裂,本发明Ni百分含量为0.30%~0.45%;
Cr是在实际工业生产中应用比较广泛,它对提高钢的屈服强度仅次于碳元素,对降低屈强比不利,且我国铬元素储量较少,所以降低了铬元素的含量,用Mn及Si元素代替,本发明Cr 百分含量为0.45%~0.60%;
Mo是较强的固溶强化元素,强烈提高淬透性,可明显提高热硬性,并提高回火稳定性,显著降低回火脆性,本发明Mo百分含量为0.16%~0.25%;
V是中等程度的碳化物形成元素,可形成简单立方晶体结构的合金碳化物VC,可进入渗碳体提高渗碳体稳定性,提高回火稳定性,本发明V百分含量为0.010%~0.030%;
Ti可使C曲线右移,钛能显著提高强度,起到细化晶粒作用,也可提高钢的韧性,适量的Ti可以形成第二项质点,提高金属的韧性,本发明Ti百分含量为0.010%~0.020%。
附图说明
图1为实施例3中钢板的500倍光学金相组织图。
具体实施方式
实施例1
本实施例的550MPa级低屈强比耐候桥梁钢,其成分及质量百分比含量为:C:0.06%、Si:0.27%、Mn:1.65%、P:0.014%、S:0.0010%、Nb:0.020%、Ti:0.015%、V:0.010%、Ni:0.30%、Cu:0.35%、Cr:0.45%、Mo:0.18%、Alt:0.02%,余量为Fe及不可避免杂质。
原料通过冶炼、精炼、合金化、钙处理,得到钢水,钢水上板坯连铸,铸坯厚度为150mm的坯料,耐大气腐蚀性指数I为6.56。铸坯堆冷24小时以上,把坯料在1230℃下均热,温度均匀性小于20℃,加热150min后进行除鳞,随后进行两阶段轧制。再结晶区轧制温度是1080℃,总变形量为79%,中间坯厚度控制在成品厚度4倍。未再结晶区轧制开轧温度为990℃,达到最终产品厚度8mm,终轧为830℃。
终轧后进行弛豫至始冷温度730℃,对在始冷温度下的钢板进行层流冷却,返红温度为600℃,而后空冷至室温,然后对钢板进行回火,回火温度在600℃,并在此温度下保温20min。
对控轧控冷+回火后的试样金相组织进行观察发现,显微组织类型为“回火贝氏体”组织,材料的屈服强度为592MPa,抗拉强度为698MPa,成品钢屈强比为0.85,-40℃Akv为188J,延伸率A为20%。
实施例2
本实施例的550MPa级低屈强比耐候桥梁钢,其成分及质量百分比含量为:C:0.08%、Si:0.30%、Mn:1.60%、P:0.009%、S:0.0012%、Nb:0.035%、Ti:0.020%、V:0.017%、Ni:0.34%、Cu:0.30%、Cr:0.60%、Mo:0.16%、Alt:0.04%,余量为Fe及不可避免杂质。原料通过冶炼、精炼、合金化、钙处理,得到钢水,钢水上板坯连铸,铸坯厚度为320mm的坯料,耐大气腐蚀性指数I为6.67。铸坯堆冷48h以上,把坯料在1150℃均热,温度均匀性小于20℃,加热336min后进行除鳞,随后进行两阶段轧制。再结晶区轧制温度是1060℃,总变形量为53%,中间坯厚度控制在成品厚度2.5倍。未再结晶区轧制开轧温度为840℃,达到最终产品厚度60mm,终轧温度为800℃。
终轧后进行弛豫处理至始冷温度750℃,对在始冷温度下的钢板进行层流冷却,返红温度为450℃,而后空冷至室温,然后对钢板进行回火,回火温度在550℃,并在此温度下保温35min。
对控轧控冷+回火后的试样金相组织进行观察发现,显微组织类型为“回火贝氏体”组织,材料的屈服强度为583MPa,抗拉强度为703MPa,成品钢屈强比为0.83,-40℃Akv为215J,延伸率A为21%。
实施例3
本实施例的550MPa级低屈强比耐候桥梁钢,其成分及质量百分比含量为:C:0.09%、Si:0.15%、Mn:1.55%、P:0.011%、S:0.0020%、Nb:0.040%、Ti:0.017%、V:0.030%、Ni:0.45%、Cu:0.34%、Cr:0.50%、Mo:0.25%、Alt:0.02%,余量为Fe及不可避免杂质。原料通过冶炼、精炼、合金化、钙处理,得到钢水,钢水上板坯连铸,铸坯厚度为320mm的坯料,耐大气腐蚀性指数I为6.58。铸坯堆冷48h以上,把坯料在1130℃均热,温度均匀性小于20℃,加热320min后进行除鳞,随后进行两阶段轧制。再结晶区轧制温度是1040℃,粗轧总变形量为50%,中间坯厚度控制在成品厚度2.0倍。未再结晶区轧制开轧温度为780℃,达到最终产品厚度80mm,终轧温度为770℃。
终轧后进行弛豫处理至始冷温度760℃,对在始冷温度下的钢板进行层流冷却,返红温度为400℃,而后空冷至室温,然后对钢板进行回火,回火温度在500℃,并在此温度下保温40min。
对控轧控冷+回火后的试样金相组织进行观察发现,低倍镜下的显微组织类型为“回火贝氏体”组织,组织结构的均匀性好,材料的屈服强度为578MPa,抗拉强度为705MPa,成品钢屈强比为0.82,-40℃Akv为204J,延伸率A为22%。
实施例4
本实施例的550MPa级低屈强比耐候桥梁钢,其成分及质量百分比含量为:C:0.07%、Si:0.21%、Mn:1.51%、P:0.015%、S:0.0015%、Nb:0.050%、Ti:0.010%、V:0.020%、Ni:0.41%、Cu:0.40%、Cr:0.48%、Mo:0.20%、Alt:0.025%,余量为Fe及不可避免杂质。原料通过冶炼、精炼、合金化、钙处理,得到钢水,钢水上板坯连铸,铸坯厚度为260mm的坯料,耐大气腐蚀性指数I为6.55。铸坯堆冷36h以上,把坯料在1200℃均热,温度均匀性小于20℃,加热286min后进行除鳞,随后进行两阶段轧制。再结晶区精轧温度是1100℃,粗轧总变形量为63%,中间坯厚度控制在成品厚度3.0倍。未再结晶区轧制开轧温度为870℃,达到最终产品厚度32mm,终轧温度为820℃。
终轧后进行弛豫处理至始冷温度740℃,对在始冷温度下的钢板进行层流冷却,返红温度为540℃,而后空冷至室温,然后对钢板进行回火,回火温度在530℃,并在此温度下保温30min。
对控轧控冷+回火后的试样金相组织进行观察发现,显微组织类型为“回火贝氏体”组织,材料的屈服强度为586MPa,抗拉强度为724MPa,成品钢屈强比为0.81,-40℃Akv为333J,延伸率A为21%。
从上述实施例可知,采用中厚板轧机生产的这种550MPa级低屈强比耐候桥梁钢,通过其成分设计辅助控轧控冷+离线回火的制造工艺,有效的降低了耐候桥梁钢的屈强比,能够保证成品钢的屈强比≤0.85。
除上述实施例外,本发明还可以有其他实施方式。凡采用等同替换或等效变换形成的技术方案,均落在本发明要求的保护范围。
Claims (8)
1.一种低屈强比耐候桥梁钢,其特征在于:其化学成分及质量百分比如下:C:0.06%~0.09%、Si:0.15%~0.30%、Mn:1.51%~1.65%、P:0.009%~0.015%、S≤0.002%、Nb:0.020%~0.050%、Ti:0.010%~0.020%、V:0.010%~0.030%、Cu:0.30%~0.40%、Ni:0.30%~0.45%、Cr:0.45%~0.60%、Mo:0.16%~0.25%、Alt:0.02%~0.04%,余量为Fe及不可避免的夹杂。
2.根据权利要求1所述的一种低屈强比耐候桥梁钢,其特征在于:其化学成分及质量百分比如下:C:0.06%~0.07%、Si:0.20%~0.30%、Mn:1.56%~1.65%、P:0.011%~0.015%、S≤0.002%、Nb:0.020%~0.040%、Ti:0.010%~0.020%、V:0.010%~0.030%、Cu:0.32%~0.36%、Ni:0.35%~0.45%、Cr:0.45%~0.60%、Mo:0.16%~0.20%、Alt:0.02%~0.04%,余量为Fe及不可避免的夹杂。
3.根据权利要求1所述的一种低屈强比耐候桥梁钢,其特征在于:其化学成分及质量百分比如下:C:0.07%~0.09%、Si:0.17%~0.20%、Mn:1.54%~1.59%、P:0.009%~0.015%、S≤0.002%、Nb:0.030%~0.040%、Ti:0.010%~0.020%、V:0.015%~0.025%、Cu:0.30%~0.35%、Ni:0.30%~0.40%、Cr:0.45%~0.55%、Mo:0.20%~0.25%、Alt:0.02%~0.04%,余量为Fe及不可避免的夹杂。
4.一种低屈强比耐候桥梁钢制备方法,其特征在于:应用于权利要求1-3任意一项,包括冶炼、连铸、均热、轧制、弛豫、冷却以及离线回火:
采用的连铸坯厚度为150~320mm,连铸工序的连铸坯堆冷24h以上;连铸坯在均热工序中加热至中心温度为1130~1230℃,温度均匀性小于20℃,加热时间≥连铸坯厚度×1min/mm;
轧制工序是对除鳞后的连铸坯进行再结晶区轧制和未再结晶区轧制,再结晶区轧制的累积变形量为连铸坯厚度的50%以上;
中间坯待温780~990℃,待温厚度为2.0~4.0倍的成品厚度,到温后进行未再结晶区轧制,终轧温度控制在770~830℃;
弛豫工序中,弛豫至始冷温度为730℃~760℃;
冷却工序是自始冷温度进行层流冷却,返红温度控制在400~600℃,随后空冷至室温;
离线回火工序中,回火温度在500~600℃,并在此温度下保温20~40min,且保温时间与成品厚度成正比,随后自然冷却至室温。
5.根据权利要求4所述的一种低屈强比耐候桥梁钢制备方法,其特征在于:连铸坯的厚度增大,堆冷的时间随之增大,对于320mm的连铸坯,堆冷时间在48h以上。
6.根据权利要求4所述的一种低屈强比耐候桥梁钢制备方法,其特征在于:钢板厚度8~80mm。
7.根据权利要求4所述的一种低屈强比耐候桥梁钢制备方法,其特征在于:钢板屈服强度578MPa以上,抗拉强度698MPa以上,屈强比≤0.85,-40℃Akv在188J以上,延伸率≥20%;耐大气腐蚀性指数I≥6.5,I=I=26.01(%Cu)+3.88(%Ni)+1.20(%Cr)+1.49(%Si)+17.28(%P)-7.29(%Cu)(%Ni)-9.10(%Ni)(%P)-33.39(%Cu)2。
8.根据权利要求4所述的一种低屈强比耐候桥梁钢制备方法,其特征在于:钢板金相组织为回火贝氏体。
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210868018.8A CN115341141A (zh) | 2022-07-22 | 2022-07-22 | 一种低屈强比耐候桥梁钢及制备方法 |
PCT/CN2022/114327 WO2024016419A1 (zh) | 2022-07-22 | 2022-08-23 | 一种低屈强比耐候桥梁钢及制备方法 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210868018.8A CN115341141A (zh) | 2022-07-22 | 2022-07-22 | 一种低屈强比耐候桥梁钢及制备方法 |
Publications (1)
Publication Number | Publication Date |
---|---|
CN115341141A true CN115341141A (zh) | 2022-11-15 |
Family
ID=83950188
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202210868018.8A Pending CN115341141A (zh) | 2022-07-22 | 2022-07-22 | 一种低屈强比耐候桥梁钢及制备方法 |
Country Status (2)
Country | Link |
---|---|
CN (1) | CN115341141A (zh) |
WO (1) | WO2024016419A1 (zh) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN116145034A (zh) * | 2023-01-03 | 2023-05-23 | 南京钢铁股份有限公司 | 一种耐海洋大气腐蚀的结构用345MPa级钢板的制造方法 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111455287A (zh) * | 2020-03-30 | 2020-07-28 | 南京钢铁股份有限公司 | 一种500MPa级低屈强比耐候桥梁钢及其制造方法 |
WO2021098208A1 (zh) * | 2019-11-20 | 2021-05-27 | 南京钢铁股份有限公司 | 690MPa级高强度低屈强比中锰钢中厚钢及制造方法 |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5136156B2 (ja) * | 2008-03-28 | 2013-02-06 | Jfeスチール株式会社 | 超大入熱溶接熱影響部靭性に優れた低降伏比高張力厚鋼板およびその製造方法 |
CN102851615A (zh) * | 2011-06-28 | 2013-01-02 | 鞍钢股份有限公司 | 抗拉强度800MPa级别低屈强比结构钢板及其制造方法 |
CN103614630A (zh) * | 2013-11-14 | 2014-03-05 | 南京钢铁股份有限公司 | 一种高强桥梁用钢及其制备方法 |
CN108531808B (zh) * | 2018-05-07 | 2020-01-14 | 武汉钢铁有限公司 | 一种屈服强度≥690MPa的低屈强比耐候桥梁用结构钢及生产方法 |
CN111020376A (zh) * | 2019-11-14 | 2020-04-17 | 舞阳钢铁有限责任公司 | 低屈强比高韧性770MPa级耐候桥梁钢板及生产方法 |
CN111996460B (zh) * | 2020-09-02 | 2021-06-29 | 燕山大学 | 一种焊接热影响区-40℃冲击功不低于54J的500MPa级耐候桥梁钢 |
CN112831717B (zh) * | 2020-12-03 | 2022-04-19 | 南京钢铁股份有限公司 | 一种690MPa级低屈强比薄规格耐候桥梁钢及其制造方法 |
CN114645201B (zh) * | 2022-03-14 | 2023-05-05 | 安阳钢铁股份有限公司 | 一种高韧性Q500qNH桥梁耐候钢板及制造方法 |
-
2022
- 2022-07-22 CN CN202210868018.8A patent/CN115341141A/zh active Pending
- 2022-08-23 WO PCT/CN2022/114327 patent/WO2024016419A1/zh unknown
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2021098208A1 (zh) * | 2019-11-20 | 2021-05-27 | 南京钢铁股份有限公司 | 690MPa级高强度低屈强比中锰钢中厚钢及制造方法 |
CN111455287A (zh) * | 2020-03-30 | 2020-07-28 | 南京钢铁股份有限公司 | 一种500MPa级低屈强比耐候桥梁钢及其制造方法 |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN116145034A (zh) * | 2023-01-03 | 2023-05-23 | 南京钢铁股份有限公司 | 一种耐海洋大气腐蚀的结构用345MPa级钢板的制造方法 |
Also Published As
Publication number | Publication date |
---|---|
WO2024016419A1 (zh) | 2024-01-25 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN111455287B (zh) | 一种500MPa级低屈强比耐候桥梁钢及其制造方法 | |
CN112831717B (zh) | 一种690MPa级低屈强比薄规格耐候桥梁钢及其制造方法 | |
CN112981235B (zh) | 一种屈服强度420MPa级的调质型建筑结构用钢板及其生产方法 | |
WO2021098208A1 (zh) | 690MPa级高强度低屈强比中锰钢中厚钢及制造方法 | |
CN111455269A (zh) | 屈服强度960MPa级甚高强度海工钢板及其制造方法 | |
CN113957346B (zh) | 一种屈服强度不小于500MPa高性能桥梁钢及其制备方法和应用 | |
CN114411059A (zh) | 一种桥梁钢及其制造方法 | |
CN112226673A (zh) | 一种抗拉强度650MPa级热轧钢板及其制造方法 | |
KR20240099374A (ko) | 내후성이 우수한 고강도 스틸 및 이의 제조방법 | |
CN114381658B (zh) | 一种800MPa级低焊接裂纹敏感性钢板及其制造方法 | |
CN114480962B (zh) | 一种620MPa级煤矿液压支架用钢及其制造方法 | |
CN115341141A (zh) | 一种低屈强比耐候桥梁钢及制备方法 | |
WO2024146073A1 (zh) | 一种耐海洋大气腐蚀的结构用345MPa级钢板的制造方法 | |
CN116875902A (zh) | 一种船舶用耐磨蚀钢板及制造方法 | |
CN113737108A (zh) | 一种耐延迟开裂的电镀锌超强双相钢及其制造方法 | |
CN115491607A (zh) | 一种耐海洋大气腐蚀的结构用钢板及制备方法 | |
CN115558851A (zh) | 一种370MPa级别工程结构用热轧钢板及其制造方法 | |
CN115572901A (zh) | 一种630MPa级高调质稳定性低碳低合金钢板及其制造方法 | |
CN114480976A (zh) | 一种高温轧制Q420qE桥梁结构钢板及其生产方法 | |
CN114231826A (zh) | 一种Q420qE桥梁结构钢板的生产方法 | |
CN114134387A (zh) | 一种抗拉强度1300MPa级厚规格超高强钢板及其制造方法 | |
CN115074639A (zh) | 一种抗拉强度600MPa级汽车大梁用热轧钢板 | |
CN115786806B (zh) | 一种具有良好低温韧性的高强度低碳当量特厚钢板及其制造方法 | |
WO2024109880A1 (zh) | 一种纳米析出物强化超高强钢及其制造方法 | |
CN117448704A (zh) | 一种耐环境腐蚀的经济型450MPa级冷轧钢及生产方法 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
RJ01 | Rejection of invention patent application after publication | ||
RJ01 | Rejection of invention patent application after publication |
Application publication date: 20221115 |