核电承压设备用钢SA738Gr．B焊接性能试验研究

本文通过对SA738Gr．B钢焊接冷裂纹敏感性试验、手工焊和埋弧焊焊接试验,分析了钢板焊接冷裂纹敏感性和焊接接头的综合力学性能及显微组织,结果表明武钢SA738Gr．B钢具有优异的焊接性能,能够满足我国极寒地区核电站用钢要求。     

60Si2Mn钢摩擦焊后热处理工艺的改进

对60Si2Mn钢摩擦焊焊接接头热处理后的组织和性能进行了研究,通过显微镜(OM)观察焊缝的界面层显微组织形貌特征,分析了热处理工艺对焊接接头性能的影响.结果表明:该钢摩擦焊焊接接头为珠光体+铁素体+马氏体组织,组织不均匀.经正火预处理后,焊接接头为细小粒状珠光体,再进行淬火加回火处理,组织均匀,为回火索氏体,焊缝下屈...     

超高强钢的摩擦焊工艺研究

目的研究某产品摩擦焊的工艺性能。方法研究了超高强钢45CrNiMo1VA钢在不同摩擦焊接工艺参数下的接头组织与性能,以及在不同热处理回火温度下对焊接接头强度的影响。结果在合适的工艺参数下,45CrNiMo1VA钢的高韧性可以有效保证焊接接头韧性,满足产品高指标的要求,使焊接接头组织具有良好的组织性能,焊后热处理工艺的正确确定是保证焊缝组织性能与母材组织性能的重要保证。结论试验证明超高强钢(45CrNiMo1VA)完全可以应用于摩擦焊生产中,并能获得理想的性能指标。     

船用铝-钢复合过渡接头焊接试验研究

通过模拟焊后热处理试验,分析了界面温度与界面结合强度的关系,并以此为基础进行了船用铝-钢复合过渡接头焊接工艺试验。试验结果表明,铝-钢复合过渡接头焊后的组织和性能均能满足相关标准和产品技术协议的指标要求。     

321-Q370q复合板焊接性能试验研究

桥梁结构复杂,构件制作时需大量采用焊接,焊接的方法主要是埋弧自动焊,为了验证321-Q370q复合板能否满足桥梁用钢的焊接要求,对复合板埋弧焊接头进行了一系列性能试验。试验结果表明,焊接接头各项性能均能满足相关标准要求。     

双面双弧焊对高强钢焊接效率和质量影响分析

对高强钢10CrNi3MoV钢厚板进行了双面双弧焊接试验研究。结果表明,焊接长2 m、厚50 mm的钢板,双面双弧焊与传统单弧MAG焊相比,生产效率提高1.4倍,焊接接头力学性能满足指标要求;双面双TIG打底的热影响区金相组织为板条状马氏体,焊缝区为板条马氏体+针状铁素体。     

煤矿机械用Q690高强钢激光-MAG复合焊可行性分析

目的研究激光-MAG复合焊在采煤机Q690高强钢板上的加工工艺,以提高8.8 m高端采煤机电控箱结构焊接接头的加工效率和质量性能。方法对激光-MAG复合焊工艺试验进行试验设计与参数设计,观察接头的显微组织,对接头进行拉伸试验和冲击试验,观察断口形貌。结果焊缝区整体组织性能优于母材,保证采煤机电控箱隔爆性能要求,拉伸断口和冲击断口均表现为韧性断口形貌,但是在冲击断口上观察到明显的气孔。焊缝内存在微量气孔,导致焊接接头结合不紧密,拉伸试验出现了脆性断裂。结论避免焊接工艺设计中出现气孔是激光-MAG复合焊焊接接头满足Q690钢在煤矿机械中使用要求的关键技术。     

基于添加铜过渡层的钛钢异种金属真空扩散焊研究

研究了添加铜箔过渡层进行扩散焊接的纯钛TA2和14MnMoVN钢焊接接头的组织和性能。采用OM、扫描电镜、能谱分析和X射线衍射分析对扩散焊接界面的微观组织、元素扩散和组织结构进行分析观察,通过拉伸试验对接头力学性能进行测试。结果表明:通过添加铜过渡层进行扩散焊接可以获得有效连接的钛/钢异种金属复合接头。结合良好的界面可以划分为接头元素扩散过渡区和铜钛结合区。其中钛向铜扩散,少量铁向铜扩散,这是三种元素的综合扩散过渡区。铜钛结合区是铜向钛扩散的区域,主要产生大量的铜钛金属间化合物。接头拉伸强度可以达到299 MPa,断裂位置位于铜钢结合区。     

高强钢多道焊接头显微组织及力学性能

研究了10Ni3CrMoV钢以衬垫半自动CO2气体保护焊打底,并以埋弧焊盖面的多道焊焊接接头各个区域显微组织以及力学性能的变化。对20mm厚的对接接头熔合区、母材区和热影响区进行V型缺口冲击试验和硬度测试。结果表明:焊接接头抗拉强度都高于母材,且弯曲试验结果都合格,满足塑性要求;热影响区的冲击功最低而硬度值最大,通过金相分析可知,该区的低冲击功和高硬度是由其铸造组织以及在晶界出现的第二相所导致的。     

1Cr17与1Cr18Ni9Ti异种钢的焊接

在分析1Cr17与ICr18Ni9Ti各自焊接性的基础上,根据异种钢接接头焊缝金属成分与组织,选择不同焊接材料进行工艺试验,依据试验结果成功地焊接了异种钢接头。     

16Co14Ni10Cr2MoA超高强度钢焊接接头组织和性能的研究

介绍了１６Ｃｏ１４Ｎｉ１０Ｃｒ２ＭｏＡ超高强度钢氩弧焊接头的力学性能，与４０ＣｒＭｎＳｉＭｏＶＡ超高强度钢的焊接接头作了对比分析，并借助金相和电镜对接头组织进行了分析。结果表明，该超高强钢的焊接性良好，不仅接头强度高，而且塑性和韧性仍保持很高水平。     

0Cr13Ni5Mo/Q345C马氏体不锈钢复合板的焊接性

分析了 0Cr13Ni5Mo/Q345C马氏体不锈钢复合板的焊接性。通过抗裂性试验、复合板补焊及复合板对接焊、焊接工艺评定 ,提出了该复合板配套的焊接材料及可行的焊接工艺 ,按此工艺焊接的 0Cr13Ni5Mo/Q345C复合钢板接头的力学性能满足技术指标的要求。     

Effect of welding wire and groove angle on mechanical properties of high strength steel welded joints

Mechanical properties of high strength steel welded joints strictly depend on the welding process, the filler material composition and the welding geometry. This study investigates the effects of using cored and solid welding wires and implementing various groove angles on the mechanical performance of weld joints which were fabricated employing the gas metal arc welding process. It was found that weld joints of low alloy, high strength steels using low alloy steel cored welding wires exhibited higher tensile strength than that of low alloy steel solid wire and chromium‐nickel steel bare welding wire when the method of gas metal arc welding is employed. The effect of groove angle on the strength and toughness of V‐groove and double V‐groove butt‐joints was investigated. V‐groove joints, with higher tensile strength than double V‐groove joints in the whole range of groove angles, were superior in toughness for small groove angles, but impact toughness values of both joints were comparable for large angles. The effect of heat input and cooling rate on the weld microstructure and weld strength was also investigated by performing thermal analysis employing the commercial software ANSYS. It was concluded that cooling rate and solidification growth rate determined the microstructure of the weld zone which had great consequences in regard to mechanical properties.     

用四点弯曲试验确定焊接接头的薄弱区

通过全厚度的四点弯曲试验确定了 14MnNbq钢焊接接头的薄弱区 ,该方法简单直观 ,其结果得到了冲击试验的验证     

Study of Microstructure and Properties of Non-Electric Welded Joints

Non-electric welding, which combines the advantages of traditional welding and Self-propagating Hightemperature Synthesis (SHS), is a newly developed technology because of its simple process and no energy supplement during welding. In this paper, two pieces of 45 steel sheets were welded by Non-electric welding, and the properties of joints were studied. The microstructure and mechanical properties were investigated by SEM, EDAX, hardness tester and tensile tester.The interfaces of the joints and matrix show excellent metallurgical bonding, and the elements of joints have diffused into substrate. Welded joints have high mechanical properties. The bonding strength can reach 348 MPa, and the impact toughness is 44 J/cm2. Non-electric welding technology also can weld non-ferrous, and this technology especially suited to be used at the emergent maintenance of field.     

S275低合金钢焊接接头的组织与力学性能

通过拉伸、冲击、硬度测试和金相检验等方法对S275低合金钢熔化极活性气体保护焊(MAG)焊接接头的力学性能与显微组织进行了研究。结果表明:采用JM一56焊丝对S275低合金钢进行焊接时,接头具有较好的抗剪强度;开45。坡口,拉伸后均断在离焊缝位置较远的母材上,焊接接头抗拉强度满足技术要求。焊缝组织晶内为细小密集的针状铁素体,有极少量珠光体,焊缝局部有魏氏组织;熔合区、过热区为沿晶界析出的块状先共析铁素体和向晶内生长的条状铁素体以及少量的珠光体;正火区组织为细小的铁素体和珠光体;母材组织为铁素体和珠光体,晶粒也比较细小。最后得出S275低合金钢用于转向架焊接构架是可行的。     

Weldability and properties of martensitic/austenitic stainless steel joints

Abstract

A series of studies has been carried out to examine the weldability and properties of dissimilar steel joints using martensitic and austenitic stainless steels F6NM (OCr13Ni4Mo) and AISI 347, respectively. This type of joint requires good mechanical properties, corrosion resistance, and a stable magnetic permeability in addition to a good weldability. Weldability tests include weld thermal simulation of the martensitic steel to investigate the influence of weld thermal cycles and post-weld heat treatment (PWHT) on the microstructure and mechanical properties of the heat affected zone (HAZ); implant testing to examine the tendency for cold cracking of martensitic steel; and rigid restraint testing to determine hot crack susceptibility of the multipass dissimilar steel joints. The simulation results indicated that the toughness of the martensitic steel HAZ did not change significantly after the weld thermal cycles. The implant test results indicated that welds produced using nickel based filler show no tendency for cold cracking, whereas welds produced using martensitic or ferritic filler show such a tendency. Based on the weldability tests, a welding procedure (tungsten inert gas welding for root passes with HNiCrMo-2B wire followed by manual metal arc welding using ENiCrFe-3B coated electrode) was developed and a PWHT at 600°C for 2 h was recommended. Joints produced using the developed welding procedure are not susceptible to hot and cold cracking. After PWHT the joints exhibit both satisfactory mechanical properties and stress corrosion cracking resistance.

MST/1955     

Effect of the welding mode and filler content on the structure of microalloyed Nb/Ti steel weldments

We describe the changes in the proportions of some microconstituents in the structure of the weld metal and the heat-affected zone and analyze the mechanical and technological properties of the welded joints of high-strength microalloyed Nb/Ti steel made by the E-process and MAG-process of welding with modification of the composition of the filler and welding parameters. The influence of different structures of the filler material and welding parameters on the microstructures of the HAZ and weld metal is studied with an aim to explain the changes in the mechanical and technological properties of the welded joints of microalloyed Nb/Ti steel.     

317L/FH40复合钢板堆焊接头性能和组织研究

采用优选工艺参数对8 mm+48 mm厚的317L/FH40复合钢板进行了复层堆焊(补焊)焊接,然后进行焊后热处理,并对接头进行力学性能测试和微观组织分析。结果表明,317L/FH40复合板堆焊接头各项力学性能测试结果均达到相关标准要求,能够满足实际工程需要;金相组织分析结果显示,复层317L热影响区出现晶粒长大的现象,基层FH40钢热影响区组织产生变化;显微硬度测试结果显示接头各区域内硬度波动不大,不同区域间硬度呈现差异,局部出现升高和降低现象;晶间腐蚀试验结果显示复层堆焊焊缝无晶间腐蚀倾向。     

焊接电流对X80钢低温焊接接头组织与性能的影响

通过显微组织分析、硬度测试、拉伸试验、冲击试验、腐蚀试验,利用扫描电子显微镜(SEM)、能谱仪(EDS)和X射线衍射(XRD)等实验手段,研究了焊条电弧焊(SMAW)不同焊接电流对X80钢低温焊接接头组织与性能的影响。结果表明:随着焊接电流增加,热影响区(HAZ)晶粒粗化,并且软化现象更加明显;焊接电流在180~190A的接头综合力学性能最佳,但当电流增加到190~200A时,接头的综合力学性能显著降低;各组接头腐蚀速率相差不大,范围在0.14~0.19g/(m2·h),腐蚀膜具有较好的致密性,能够阻止腐蚀介质对基体继续进行腐蚀,从而达到较好的耐腐蚀效果。