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个人中心收藏查看我的收藏0有用+10播报讨论上传视频低合金高强度结构钢牌号是符合GB/T 1591标准的低合金高强度结构钢，其屈服强度不低于460MPa，兼具良好塑韧性及焊接性能。该钢材采用碳、硅、锰为主要合金元素，辅以铬、镍、钼等微量元素强化，通过TMCP控轧控冷工艺实现高强度与工艺性能平衡。广泛应用于桥梁、建筑、工程机械等领域，可承受大跨度重载工况。其加工适应性覆盖电弧焊、等离子切割等多种成型工艺，支持Z向抗层状撕裂性能定制 [1]。执行标准GB/T 1591
化学成分C≤0.20%、Mn≤1.70%
交货状态热轧/正火
适用厚度≤50mm [1]
应用领域起重机、液压机、矿山机械、工程机械（铲车/挖掘机）、农业机械等制造领域
加工方式数控切割

目录
1材质特性2化学成分设计3生产工艺4力学性能5应用领域6加工规范7质量检测
材质特性
播报编辑属于高强度低合金结构钢，名称中"Q"代表屈服强度，"460"表示最小屈服强度值（MPa），"D"对应质量等级。通过微合金化与控轧工艺结合，在保证460MPa屈服强度的同时，抗拉强度可达550-700MPa，断后伸长率最高达26% [1]。常温下0℃冲击功达标，厚度方向断面收缩率根据Z15/Z25/Z35分级控制，满足不同抗震需求。碳当量设计≤0.42%，显著提升焊接性能，避免冷裂纹产生 [1]。
化学成分设计
播报编辑核心成分控制范围包括：碳元素：0.14-0.17%（专利设计）/≤0.20%（通用标准） [1]锰元素：1.45-1.55%（专利强化方案） [1]微量元素：复合添加钒、铌、钛，总量≤0.20% [1]杂质元素严格限制：磷≤0.030%（通用标准）/≤0.018%（专利工艺） [1]硫≤0.025%（通用标准）/≤0.005%（专利工艺） [1]
生产工艺
播报编辑采用九道关键工序制备：1.KR铁水脱硫预处理，硫含量降至≤0.018% [1]2.转炉双渣法冶炼，终点碳氧积≤0.0025 [1]3.LF精炼白渣保持≥10分钟，精确成分微调 [1]4.连铸全程氩气保护浇注，过热度控制15-25℃ [1]5.三阶段轧制加热，最高温度1240℃ [1]6.TMCP控轧，开轧温度1050-1150℃ [1]7.层流冷却，冷速10-15℃/s [1]8.下线堆垛缓冷≥24小时 [1]9.超声波探伤检测（一/二/三级标准）
力学性能
播报编辑经检测数据显示：屈服强度：470-490MPa（专利工艺）/≥460MPa（通用标准） [1]抗拉强度：570-700MPa [1]延伸率：17-26% [1]低温冲击：-20℃冲击功≥34J硬度值：HBW 170-210
应用领域
播报编辑主要应用于三类工程场景：重型机械制造工程机械：起重机、挖掘机、矿山机械矿山设备：起重机、液压机、矿山机械、工程机械（铲车/挖掘机）农业机械：工程机械（铲车/挖掘机）建筑桥梁工程大跨度桥梁：主梁、拱肋、桥面板高层建筑：建筑框架/支撑体系场馆结构：桥梁主梁/横梁/拱肋、建筑框架/支撑体系特种运输装备船舶结构：桥梁主梁/横梁/拱肋、建筑框架/支撑体系、船舶及车辆结构件铁路车辆：工程机械（铲车/挖掘机）、农业机械等制造领域特种车辆：工程机械（铲车/挖掘机）、农业机械
加工规范
播报编辑允许采用以下加工方式：切割工艺：等离子切割（厚度≤30mm）、火焰切割（厚度＞30mm）焊接方法：手工电弧焊（J557焊条）、埋弧焊（H10Mn2焊丝+ SJ101焊剂）成型加工：冷弯成型半径≥2倍板厚，热弯温度850-900℃ [1]热处理：正火处理温度890±10℃，回火温度≤600℃
质量检测
播报编辑依据不同应用场景执行：常规检测：拉伸/弯曲/冲击试验专项检测：Z向拉伸试验（断面收缩率≥15%/25%/35%）无损检测：超声波探伤（GB/T2970 II级）金相检验：带状组织≤2级，晶粒度≥8级 [1]的图片(1张)新手上路成长任务编辑入门编辑规则本人编辑我有疑问内容质疑在线客服官方贴吧意见反馈投诉建议举报不良信息未通过词条申诉投诉侵权信息封禁查询与解封©2025 Baidu 使用百度前必读 | 百科协议 | 隐私政策 | 百度百科合作平台 | 京ICP证030173号 京公网安备11000002000001号window.PAGE_DATA= 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1591"}]}]},{"key":"customDefault","title":"化学成分","isArray":false,"delimiter":"","data":[{"dataType":"text","text":[{"tag":"text","text":"C≤0.20%、Mn≤1.70%"}]}]},{"key":"customDefault","title":"交货状态","isArray":false,"delimiter":"","data":[{"dataType":"text","text":[{"tag":"text","text":"热轧/正火"}]}]}],"right":[{"key":"customDefault","title":"适用厚度","isArray":false,"delimiter":"","data":[{"dataType":"text","text":[{"tag":"text","text":"≤50mm"},{"ctrId":"","data":{"encodeUrl":"533aYdO6cr3_z3kATKfexPmhMy3CNIyt6rLWAeFzzqIP0XOpW5rkToExrsM2__l-FQXIuJksY9kY2firTh4bquhDLrNxF-tm_QKJTDbBnb3hrotlnYVMoNhFC6tDh_WgsEP5gybZ3bDdv2-yiiTJsJb2O2ORHIgc","index":1,"publishDate":"2024-03-21","site":"static.tianyancha.com","title":"(12)发明专利 50m以下低合金高强度结构用钢及其 生产方法 50mm以下低合金高强度结构用钢及其生产方法 ","type":1,"uuid":"i2msi60jj5"},"index":1,"old":false,"tag":"ref","uuid":"i2msi60jj5"}]}]},{"key":"customDefault","title":"应用领域","isArray":false,"delimiter":"","data":[{"dataType":"text","text":[{"tag":"text","text":"起重机、液压机、矿山机械、工程机械（铲车/挖掘机）、农业机械等制造领域"}]}]},{"key":"customDefault","title":"加工方式","isArray":false,"delimiter":"","data":[{"dataType":"text","text":[{"tag":"text","text":"数控切割"}]}]}]},"lemmaCnt":1,"tips":{"isPolyseme":0},"encodeLemmaId":"1350e48609f3427c0818a603","versionUk":"WbE5bnYQZYusmmQOGSvcgg","description":"是符合GB/T 1591标准的低合金高强度结构钢，其屈服强度不低于460MPa，兼具良好塑韧性及焊接性能。该钢材采用碳、硅、锰为主要合金元素，辅以铬、..."}window.__abbaidu_2020_subidgetf||(window.__abbaidu_2020_subidgetf=function(){return"01000000"}) 简介Q460D，低合金高强度钢板。它的钢号冠以“Q”，代表钢材的屈服点，后面的数字表示屈服点数值，单位是MPa例如Q460表示屈服点（σs）为460MPa。D是－20度冲击。标准：GB/T 1591-2008 低合金高强度结构钢低合金高强度钢是在碳素结构钢的基础上加入少量的Mn、Si和微量的Nb、V、Ti、Al等合金元素而发展起来的一类工程结构用钢。所谓低合金是指钢中合金元素总量不超过3%。高强度是相对于碳素工程结构用钢而言。低合金高强度钢的研制原则是利用尽可能少的合金元素获得尽可能高的综合力学性能，以达到满足使用、成本低廉的目的。低合金高强度钢能够满足工程上各种结构（如大型桥梁、压力容器及船舶等）要求承载大，同时又要求减轻结构自重，提高可靠性及节约材料和资源的要求。这类钢主要用来制造各种要求强度较高的工程结构，例如桥梁、船舶、车辆、高压容器、输油输气管道、大型钢结构等。由于这类钢不用复杂的处理过程，甚至不进行热处理就可以获得较高的强度，使工程结构的质量大大减轻，因此，用这类钢来代替一般的碳素结构钢。成分特点低合金高强度钢的成分特点为低碳叫   ≤0.20%、低合金，合金元素总量   <3%。低碳含量是为了满足工程结构件用钢的塑性、韧性、焊接性和冷变形等工艺性能要求；加入以Mn为主的少量合金元素，达到了提高力学性能的目的。低合金高强度钢以Mn为主加元素，符合我国的资源特点。Mn不仅对铁素体有显著的强化效果，还可降低钢的冷脆温度，并使钢中珠光体数量增加，进一步提高强度；为进一步改善和提高钢的性能。还加入微量V、Ti、Nb、AI等细化晶粒元素，不仅进一步提高了强度，还使钢的韧性得到改善。这类钢有时还加入稀土元素Re以消除钢中的有害杂质，改善夹杂物的形态及分布，减弱其冷脆性。少量合金元素对改善和提高钢的力学性能效果显著，如在Q235中仅加入1%Mn，就成为Q345钢，而其强度却增加近40%，达345 MPa；在16Mn的基础上再加0.04～0.12%的钒，就成为Q390钢，强度由350 MPa增加至390 MPa。性能特点低合金高强度钢的合金化原理主要是利用合金元素产生的固容强化、细晶强化以及沉淀强化来提高钢的强度，同时利用细晶强化使钢的韧脆转化温度降低效应，来抵消钢中碳氮化物析出强化使钢韧脆转化温度升高这种不利的影响，使钢在获得高强度的同时又能保持较好的低温性能。低合金高强度钢的性能特点主要表现在以下两个方面。1．高的屈服极限与良好的塑性和韧性低合金高强度钢最显著的特征就是高强度。在热轧或正火状态下，低合金高强度钢一般比相应的碳素工程结构钢的强度能高出30%～50%。因而能够承受较大的载荷。工程结构一般以大型或巨型为多，构件自身的重量往往也成为载荷的重要组成部分，结构材料强度提高的同时就可以明显降低构件自重而使其承受其他载荷的能力进一步提高。不仅如此，这种良好的效应还大大提高了工程构件紧凑性从而使其可靠性进一步提高，同时减少了原材料消耗，降低了成本，节约了资源。低合金高强度钢的延伸率为15%～23%，室温下冲击吸收功   >34 J，具有良好的塑性和抗冲击性能，可避免在受冲击时发生脆断；同时使冷弯、焊接等工艺容易进行。此外，低合金高强度钢的脆性转化温度较低，其中E级质量等级的钢，在-40℃时   值不低于27 J。这对在严寒地区使用的工程构件以及运输工具如车辆、舰船、海上采油平台、容器、桥梁等具有重大意义。2．良好的焊接性能和耐大气腐蚀性能焊接是建造工程结构的最常用方法，因此工程结构用钢都要求具有良好的焊接性能。低合金高强度钢碳含量低，合金元素含量少、塑性好，在焊缝区不易产生淬火组织及裂纹，且加入的Ti、Nb、V等还能抑制焊缝区品粒长大，因此这类钢大都焊接性能优良，焊后一般不再进行热处理。工程结构大多是在大气或海洋环境中服役，低合金高强度钢中加入少量的Cu、Ni、Cr、P等元素，有效提高了工程结构抗大气、海水、土壤腐蚀的能力。如加入0.2%～0.5%的铜、0.05%～0.1%的磷以及铝等，可使钢的耐蚀性明显提高，其中铜和磷同时加入效果最佳。 [1] 发展趋势以控制轧制技术和微合金化冶金学为基础，开发了许多低合金高强度钢。低合金高强度钢的主要发展方向有以下几个方面。(1)低碳、超低碳和高纯净化。现代的工艺技术已非常先进。例如，采用顶底复吹转炉冶炼，钢的碳含量可控制在0.02%～0.03%，精炼的应用可生产出碳   =0.002%～0.003%、   <0.001%、   <0.003%、   <0.003%、   =2ppm~3ppm和   <1ppm的洁净钢。(2)微合金化钢技术。含Nb微合金化钢、Nb-V和Nb-Ti复合微合金钢几乎占有近20年来新开发微合金化钢全部牌号的75%和微合金化钢总产量的60%。微量Ti（≤0.015%）的作用十分有益，Ti的微处理不仅改变钢中硫化物的形态，而且TiO2或Ti2O3，还成为奥氏体晶内铁素体晶粒生核的质点。(3)采用控制轧制和控制冷却工艺。在再结晶控轧的基础上，应变诱导相变和析出的非再结晶控轧以及两相区形变，已成为控轧厚钢板生产主要方向。薄板坯连铸连轧流程和薄带连铸工艺的实用化，使低合金钢生产进入了又一个新境界。(4)超细晶粒化和计算机控制以及性能预报。通过加大轧制变形、铁素体的应变诱导析出、低温轧制和选择合适的冷却速度，可得到微米级的铁素体晶粒尺寸，从而大大提高钢的强度。低合金高强度钢的组织细微化是今后发展的方向。