E501T1型药芯焊丝气孔问题及防止对策

以ES01T1型药芯焊丝为例，分析了药芯焊丝在船舶焊接中气孔和凹坑问题的影响因素，从材料选择、焊接工艺控制和改善现场气保护状态等方面提出防止对策，有助于药芯焊丝的正确应用，提高了船舶焊接质量。     

高强度低合金钢的药芯电弧焊

手工电弧焊、埋弧焊,气保护钨极电弧焊和气保护金属极电弧焊工艺已广泛用于焊接高强度钢。近十年药芯焊丝研究的进展促使开发出某些用于焊接标准高强度钢以及较新型的高强度低合金(HLSA)钢的新型药芯焊丝。本文介绍了有关这些新型药芯焊丝的机械性能、焊缝金属扩散红量和所要求的焊接工艺等方面的技术资料。并将利用特定的焊接应用实例从经济角度讨论药芯电弧焊方法的优点。     

全位置自保护药芯焊丝工艺性能分析

自保护药芯焊丝多为高碱性渣系焊接材料,焊接工艺性较差。药芯组分对自保护药芯焊丝的全位置焊接性、电弧稳定性、飞溅性等工艺因素有重要影响。本文分析了Fe2O3、CaCO3、Al-Mg、BaF2及Fe粉等药芯组分对工艺性的影响。研究表明:Fe2O3、CaCO3、Al-Mg、BaF2及Fe粉的质量分数分别为9%～13%、8%～12%、10%～20%、5%～10%、40%～50%时,工艺性良好。此外,药芯组分的预处理、钢带的清洗以及填充率的控制等加工制造过程对工艺性也有重要的影响,要严格控制各个环节。     

不同焊接电流下气体保护药芯焊丝熔敷金属的显微组织及力学性能

针对一种X80管线钢用气体保护药芯焊丝，研究了不同焊接电流下其熔敷金属的显微组织及力学性能。结果表明：熔敷金属组织主要由针状铁素体、块状铁素体、粒状贝氏体组成；当焊接电流为150～250 A时，随着焊接电流的增大，组织的晶粒尺寸有增大趋势，熔敷金属的屈服强度、抗拉强度和低温冲击性能均呈现先增大后减小的趋势；当焊接电流为200 A时，熔敷金属的力学性能达到最大，焊缝组织以细小铁素体为主。     

药芯焊丝的发展及其在船舶工业中的应用

药芯焊丝具有比手工焊条、实芯焊丝更多的优点,已在世界范围内成为一种最有发展前途的高效焊接材料。本文介绍了药芯焊丝的特点、分类以及美、苏、日和欧洲各工业国家生产和使用药芯焊丝的情况,着重介绍药芯焊丝在造船工业中,尤其是在焊接HY-80、HSLA-80和HY-100等高强度钢中的应用。     

不锈钢药芯焊丝焊接电弧气氛的光谱分析

针对不锈钢药芯焊丝电弧气氛在线监测难以实现的问题,该文开展不同工艺条件下的焊接实验,采用光纤式数字光谱仪,采集不锈钢药芯焊丝气体保护焊的电弧辐射光谱信息,并对采集到的光谱信息进行标定、对比分析,获取其蕴含的电弧气氛信息,进而对其焊接过程的特点及其辐射变化规律进行研究。结果表明:该方法可对电弧气氛元素进行有效定性检测分析,为不锈钢药芯焊丝焊接电弧气氛的检测提供理论和实验基础。     

金属粉芯型气体保护焊丝在管道焊接中的应用

金属粉芯型气体保护焊丝被评价为“代替实芯焊丝的焊接材料”，它既有渣量少的实心焊丝的长处又兼备高熔敷速度、电弧柔软、焊接工艺性能好等熔渣型药芯焊丝的优点，金属粉芯焊丝现已在我国各地长输管线工程施工中得到应用。     

下向焊在长输管道的发展及应用

我单位参与承建的川气东送工程,西气东输二线平泰管道支干线工程,焊接方法为手工下向焊打底,自保护半自动药芯焊丝填充盖面,在甬沪宁战略石油管线等工程施工中也用此工艺由此看来,半自动焊在管线焊接中应用的越来越广泛。焊接材料、焊接设备是焊接技术的重要保证,因此也作介绍。同时也展望焊接技术的未来。     

焊缝根部裂纹的超声波检测

在船舶和海洋工程的焊接技术中,为了提高焊接效率,常应用陶瓷材料作为衬垫和二氧化碳作为保护气体的药芯焊丝单面填充焊接技术。但是由于焊接工艺或施工人员的错误,极易使焊缝根部产生各种危害性缺陷。本文介绍了如何用超声波检测二氧化碳气保焊的根部裂纹。     

碳钢钢带308L药芯焊丝的增碳问题

采用天津三英焊业有限责任公司首次研制成功的碳钢钢带 30 8L超低碳不锈钢药芯焊丝 ,围绕药芯焊丝的增碳问题做了大量试验。试验结果证明 ,对于任何一种焊接方法 ,碳的氧化和还原反应在焊接过程中都是同时存在的。熔敷金属中的含碳量与焊接材料中的含碳量相比是增加还是减少 ,取决于焊接材料含碳量的多少和氧化性的强弱。对于药芯焊丝 ,增碳的门槛值在 0 .0 5%左右     

An outlook on comparison of hybrid welds of different root pass and filler pass of FCAW and GMAW with classical welds of similar root pass and filler pass

In the present study, gas metal arc welding and flux cored arc welding were applied on SA516 Gr70 carbon steel material. Two different hybrid passes were applied, wherein flux cored wire and solid wire were applied to root pass and filler pass one by one and vice versa. Besides, two more welds of similar electrode root pass and filler pass of flux cored arc welding and gas metal arc welding were acquired. The comparative analysis was carried out in terms of macrostructure and microstructure examination, tensile testing, hardness variations, and impact testing for these classical welds and hybrid welds. The results reveal that, hybrid welds lead to better impact properties relative to classical welds. Maximum angular distortion of 2.66° was reported with classical weld of gas metal arc welding with solid wire root pass and same filler pass. The maximum impact toughness of 49 J/m³ was reported for flux cored root pass and solid wire filler pass at the weld zone. Maximum tensile strength of 596 MPa was reported for hybrid weld of solid root pass and flux cored filler pass. Microstructures are reported with the presence of different acicular ferrite and grain boundary ferrite. Maximum acicular ferrite of 61% was reported with classical weld of flux cored arc welding.     

Hybridization of filler wire in multi-pass gas metal arc welding of SA516 Gr70 carbon steel

In the present investigation, multi-pass gas metal arc welding (GMAW) of SA516 Gr70 carbon steel was carried out by different filler wires such as solid, metal cored and flux cored, wherein, other process parameters were kept constant. The hybrid approach of multi-pass filler wires was applied to obtain three different welds. The root pass was filled by a solid wire for all three cases while the subsequent filler pass was applied through solid, flux-cored and metal cored filler wires, respectively. Metallographic, mechanical and metallurgical analyses such as macrograph study, optical microscopy, tensile testing and hardness variations were performed to address the quality of weld. The results revealed that defect-free sound welds were produced by the hybrid approach of different filler wires in multi-pass GMAW. Overall cost and time reduction can be achieved through hybrid filler welds, without affecting their mechanical strength. Angular distortion was reported minimum at hybrid weld of solid and metal cored filler wire. Maximum reinforcement with higher penetration was observed at weld of solid and metal cored filler wire. Impact toughness was reported higher in case of hybrid weld of solid and flux cored filler wire. Higher macro hardness was reported at weld of solid and flux cored filler wire.     

Mathematical model of critical implant stress testing in the weld metal of API 5L X80 steel

In this paper the influence of heat input and preheat temperature on the critical implant stress was analyzed for the weld metal of API 5L X80. High strength steel marked as API 5L X80 is produced with a thermo – mechanical controlled process (TMCP), its chemical composition shows low carbon content due to which the steel has good weldability, but in the weld metal zone cold cracking can occure. The goal of this paper is to define optimal work conditions in form of flux cored arc welding (FCAW) welding parameters at which no cold cracks can be found. The experiment was conducted using central composite design (CCD) and design of experiments (DoE) with two independent variables (preheat temperature and heat input). Mathematical models were developed for all three different wire types that were used (two rutile, one basic flux cored wire). The samples in this paper which had cold cracks were further analyzed on the scanning electron microscope (SEM).     

船用高强钢薄板焊接成形研究

探究了不同焊接工艺对3 mm船用高强钢薄板焊接成形质量的影响.结果表明:3 mm对接试板经不同方法焊接后均呈马鞍形变化.焊条电弧焊和手工气保焊焊接的试板变形严重,且两者变形量和残余应力基本相当,药芯焊丝CMT(cold metal transfer)自动焊接试板的焊缝内部存在夹渣缺陷.利用实心焊丝CMT自动焊接试板的焊缝均匀、内部无缺陷,焊缝中心残余应力明显降低,其变形量平均值比焊条电弧焊减小37.8%,且线能量仅为焊条电弧焊的22.4%.焊接试板变形量与其线能量大小的变化趋势一致.     

国外焊接材料的发展动态及加快国产药芯焊丝发展的建议

概要地介绍了国外焊接材料（ 主要是药芯焊丝） 的发展动态,对大力发展高效焊材、改进ＭＡＧ 焊材的工艺性能及力学性能方面的工作也作了介绍,并就如何加快国产药芯焊丝产业的发展提出了建议。     

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.     

Investigation on various welding consumables on properties of carbon steel material in gas metal arc welding under constant voltage mode

In this present work, the influence of different consumables on weld properties of carbon steel plate was studied by automatic gas metal arc welding under constant voltage mode. For all experiments, the process parameters such as welding current of 200 A, voltage of 28 V and welding speed of 200 mm/min were kept constant. The results indicate that the angular distortion remained higher for solid wire, whereas it was minimum for flux-cored wire and the lowest in metal-cored wire. Mechanical properties such as yield strength, tensile strength, elongation and joint efficiency remained high for solid wire relative to cored wire. Excellent impact toughness of the weld metal and heat-affected zone was reported for the flux-cored welds compared with solid wire and metal-cored welds.     

埋弧堆焊WC颗粒增强复合层的工艺及性能

目的针对传统钢材硬度低、不耐磨损的问题,选用WC颗粒来增强传统钢材性能,研究不同工艺对WC颗粒增强钢基材料的影响。方法采用埋弧焊方法,将含有WC颗粒的药芯焊丝在钢板表面进行堆焊,采用SVS3020显微镜、光学显微镜和显微硬度计对焊缝的显微组织进行观察与分析。结果随着焊接电流、电压的增大,焊缝成形逐渐完好,无焊缝缺陷,焊接速度增大,焊缝有夹渣缺陷产生;焊缝硬度随着电流、速度的提升而增大,但随电压的提升而下降。结论埋弧焊焊接选用350 A电流、32 V电压和20 m/s速度成形的焊缝质量最佳,基体的稀释作用对堆焊合金层的显微硬度也有明显影响。     

含铌不锈钢药芯焊丝347L的研制

研究了一种GDQA347L型含铌不锈钢药芯焊丝。并对工艺性能的影响因素进行了分析。结果表明，GDQA347L型焯丝焊接工艺性能优良，力学性能和耐腐蚀性能满足要求；合适的脱氧剂比例有利于工艺性能的改善。     

船用耐海水腐蚀埋弧自动焊材料的研制

研制了一种耐海水腐蚀的埋弧焊丝,该焊丝配用３５０焊剂进行施焊,焊接接头具有优良的综合力学性能,满足了船体钢的焊接要求,填补了该强度级别耐海水腐蚀船用焊丝的国内空白。本文对该焊丝的成分设计、焊剂筛选及耐海水腐蚀性能试验等有关情况进行了介绍。