1.4003铁素体不锈钢与耐候钢对接焊试验结果及分析

采用MAG焊对1.4003铁素体不锈钢与Q345NQR2耐候钢进行对接焊,通过对焊接接头进行力学性能试验、金相组织分析、显微硬度测试、冲击试验等,研究1.4003铁素体不锈钢与Q345NQR2耐候钢2种钢的焊接工艺。结果表明：1.4003铁素体不锈钢与Q345NQR2耐候钢对接接头的力学性能良好;焊缝显微组织为奥氏体+铁素体双相组织,对焊缝的力学性能有一定的改善;1.4003不锈钢侧热影响区为粗大的多边形铁素体晶粒,Q345NQR2钢侧热影响区为片层状珠光体组织+白色铁素体;焊缝组织主要为奥氏体,硬度有所升高,1.4003不锈钢侧粗晶区由于铁素体晶粒粗大,硬度有所下降;Q345NQR2耐候钢侧热影响区粗晶区为珠光体和残余奥氏体,硬度与焊缝的相差不大;对接接头室温和-40℃下的冲击性能均比较好。     

1．4003不锈钢与0Cr18Ni9不锈钢焊接接头组织和力学性能

通过室温拉伸、室温弯曲、低温冲击、硬度试验以及金相分析对1.4003铁素体不锈钢与OCr18Ni9奥氏体不镑钢焊接接头的显微组织和力学性能进行了研究.试验结果表明:采用MAG焊焊接的1.4003铁素体不锈钢与OCr18Ni9奥氏体不锈钢,其接头的抗拉强度不低于母材的,弯曲性能良好.接头1.4003钢侧HAZ的冲击性能较差,且随温度的降低,其冲击性能显著降低.焊缝为奥氏体+铁素体双相组织,OCr18Ni9钢侧HAZ为奥氏体组织,1.4003铜侧HAZ为晶粒粗大的单一铁素体组织.     

130mm铝合金扫描激光填丝焊接头微区组织和性能

针对船用130 mm 5A06铝合金厚壁结构件的扫描激光填丝焊接头,对其焊缝（weld metal,WM）、热影响区（heat affected zone,HAZ）及母材（base metal,BM）的显微组织进行研究,并通过维氏硬度和微型剪切试验研究了接头各区力学性能差异.结果表明,5A06铝合金单激光焊缝以等轴晶为主,填丝焊焊缝以柱状晶为主,HAZ和BM晶粒比WM粗,母材及热影响区为轧制的纤维状组织;由于焊接热循环作用,接头热影响区硬度略高于母材,抗剪强度二者差别不大,单激光焊缝硬度和抗剪强度略高于填丝层.总体而言,焊缝区强度低塑性好,母材及热影响区强度高塑性低.     

不同焊接方法对超高强装甲钢焊接接头力学性能与组织的影响

装甲钢MAG工艺常采用奥氏体、铁素体不锈钢焊丝,使得焊接接头抗拉强度和硬度会大幅度降低,同时造成热影响区的局部软化,降低了装甲车辆的防护性能。为了满足超高强装甲钢焊接接头强度和硬度防护要求,该文对超高强装甲钢激光焊接工艺进行了研究,分别为MAG、激光自熔焊、激光填丝焊、激光-电弧复合焊4种焊接方法,研究接头拉伸、弯曲、硬度等性能指标及接头组织。结果表明,激光焊接头的焊缝组织为粗大的板条马氏体,MAG焊缝组织为铁素体和粒状贝氏体;对于激光焊和MAG,淬火粗晶区均为粗针状马氏体,淬火细晶区为细小的针状马氏体,不完全淬火区为马氏体与铁素体的混合组织。激光焊接头的抗拉强度和硬度远高于MAG,激光焊接头的抗拉强度可达到母材的90%以上,硬度约为母材的82%,大大提高了防护型车辆的防护性能。然而,激光焊接头的抗弯强度要低于MAG,无论面弯还是背弯,激光焊弯曲试样通常在弯曲角度10°～30°之间即发生断裂,大大低于MAG弯曲角度90°（不断裂）,从而限制了其使用场景。     

铁素体不锈钢激光-MAG复合热源焊缝成形及接头冲击韧性分析

利用激光-MAG 复合热源分别进行了 T4003 和 TCS 铁素体不锈钢的焊接试验研究.通过与常规 MAG 焊的对比,测试分析了两种焊接方法的焊缝成形、接头的低温冲击韧性及接头的微观组织.结果表明,激光-MAG 复合热源焊接易于实现铁素体不锈钢的单面焊双面成形,与常规 MAG 焊相比,其焊接效率可以提高 1 倍以上.利用激光电弧复合热源可以提高铁素体不锈钢焊接接头的低温冲击韧性,较常规 MAG 焊,复合焊接头的低温冲击韧性可以提高 50%以上.激光-MAG 复合热源焊接接头热影响区粗晶区组织宽度明显小于常规 MAG 焊接头的粗晶区宽度.

Abstract：

Laser-MAG hybrid welding of T4003 and TCS ferrite stainless steels was studied. Through comparing with the conventional MAG welding of ferrite stainless steel, the results of the two welding methods including the appearance of weld, impact toughness under low temperature and the microstructure of the butt joints were tested and analysed. The analysing results show that it is easy to get one-side welding with back by laser-MAG hybrid welding. Comparing with the conventional MAG welding, the welding efficiency of ferrite stainless steel by laser-MAG hybrid welding can be improved more than one times, the low temperature impact toughness of the joints by laser-MAG hybrid welding can be improved over 50% than that of conventional MAG welding joints, and the width of coarsegrained zone of hybrid welding joints is thinner than that of MAG welding joints.     

410S钢板焊剂带约束电弧对接焊工艺试验

410S不锈钢对焊接热输入敏感,会出现接头脆化现象。本文采用焊剂带约束电弧焊接方法,对410S热轧板进行自动化焊接试验,实现单面焊双面成形,并通过试验得出焊接工艺参数;HAZ粗晶区晶粒长大明显,硬度低,但是这种焊接方法热输入小,约为0.5 k J/mm,热影响区宽度窄,约为1.0 mm,接头抗拉强度不低于母材;HAZ组织为铁素体+马氏体,焊缝组织为铁素体+奥氏体,晶粒度为6~7级,强度高。     

430铁素体不锈钢超窄间隙焊接试验

铁素体不锈钢焊接时,需采用低热输入,以防止因热影响区晶粒粗化而导致的接头局部脆化.采用间隙宽度为3.2 mm的焊剂带约束电弧超窄间隙焊接方法,对430热轧板进行焊接试验.利用底部衬条获得了熔合良好的根焊,该方法焊接热输入可低至0.32 kJ/mm;热影响区窄,约为0.25 mm;铁素体晶粒未严重粗化,晶粒度为5.5 ～6级.采用ER309焊丝,焊接接头焊缝组织为奥氏体+板条状铁素体;在焊接热循环过程中,热影响区部分组织发生α→γ→M相变,最终组织为铁素体+马氏体;快速冷却促使铁素体晶粒内优先析出M23C6或M23(C,N)6.焊缝与母材为高强匹配,热影响区冲击韧性与母材相当.     

退火处理对P91钢管TIG焊接头组织结构及性能的影响

对P91耐热钢管结构TIG焊接头进行退火处理,并试验分析接头的显微组织和硬度分布。试验结果表明,退火后接头热影响区组织由粗大的板条马氏体转变为片状马氏体,且残余奥氏体的数量减少。退火处理后接头焊缝组织为针状或片状马氏体,且组织中存在一些铁素体组织。退火处理后接头各区域硬度变化趋于平缓,热影响区的硬度约为270~300 HV,而焊缝的硬度约为240~270 HV。770℃退火处理后焊接接头热影响区和焊缝的硬度与750℃退火处理相比稍高。硬度分布的变化与焊缝及热影响区组织结构变化密切相关。     

焊接速度对TRIP590钢激光焊接头组织性能的影响

利用金相、拉伸及硬度试验研究不同焊接速度对TRIP590钢激光焊接头组织结构及力学性能的影响。结果表明,接头热影响区(HAZ)组织主要由贝氏体、铁素体及残留奥氏体组成,焊缝区(WZ)主要由板条状马氏体组成,随焊接速度提高,马氏体板条更加细长,晶粒细化。接头宏观断裂发生在母材区,其抗拉强度与母材相当。接头焊缝区硬度达430 HV,约为母材2倍,随焊接速度提高,热影响区变窄,焊缝硬度增加。     

1Cr18Mn8Ni5N不锈钢熔焊接头组织和性能研究

采用光学显微镜、扫描电镜、电化学工作站等研究了1Cr18Mn8Ni5N不锈钢熔焊接头的显微组织、力学性能和耐腐蚀性能。结果表明:等离子弧焊(plasma arc welding,PAW)和TIG焊接头的焊缝区和熔合区组织均由铁素体和奥氏体组成。焊缝的铁素体呈骨架状和板条状,熔合区的铁素体为蠕虫状。热影响区组织为粗大的奥氏体。两种焊接接头均具有良好的力学性能,其中PAW接头比TIG接头具有更高的强度、塑性,其拉伸断口有大量细小的韧窝而呈现出更好的韧性。但PAW焊缝因含有较多的铁素体,其显微硬度略低于TIG焊。在3.5%Na Cl溶液中,PAW焊缝的耐腐蚀能力低于TIG焊缝。     

Investigation on Microstructure and Impact Toughness of Different Zones in Duplex Stainless Steel Welding Joint

This paper investigated on microstructure and impact toughness of different zones in duplex stainless steel welding joint. High-temperature heat-affected zone (HTHAZ) contained coarse ferrite grains and secondary precipitates such as secondary austenite, Cr₂N, and sigma. Intergranular secondary austenite was prone to precipitation in low-temperature heat-affected zone (LTHAZ). Both in weld metal (WM) and in HTHAZ, the austenite consisted of different primary and secondary austenite. The ferrite grains in base metal (BM) presented typical rolling texture, while the austenite grains showed random orientation. Both in the HTHAZ and in the LTHAZ, the ferrite grains maintained same texture as the ferrite in the BM. The secondary austenite had higher Ni but lower Cr and Mo than the primary austenite. Furthermore, the WM exhibited the highest toughness because of sufficient ductile austenite and unapparent ferrite texture. The HTHAZ had the lowest toughness because of insufficient austenite formation in addition to brittle sigma and Cr₂N precipitation. The LTHAZ toughness was higher than the BM due to secondary austenite precipitation. In addition, the WM fracture was dominated by the dimple, while the cleavage was main fracture mode of the HTHAZ. Both BM and LTHAZ exhibited a mixed fracture mode of the dimple and quasi-cleavage.     

焊接热循环对SA508-3钢临界粗晶区组织和性能的影响

针对核电设备用SA508-3钢临界粗晶区,采用热模拟技术研究了不预热下焊接热循环对临界粗晶区组织和性能的影响.结果表明,临界粗晶区在原奥氏体晶界上析出了项链状的隐晶马氏体组织,使其性能恶化,是焊接接头中最为薄弱的区域.临界粗晶区在经历峰值温度400~650℃的焊接热循环后,冲击韧性得到明显的改善,此时可以获得良好的强韧性匹配.在SA508-3钢多层多道焊接过程中,通过合理控制层道间焊接热循环条件,可有效改善临界粗晶区组织和性能.     

980MPa级高强钢焊接接头HAZ的组织和性能

采用焊接热模拟的方法,研究一种980 MPa级低碳贝氏体高强钢焊接接头HAZ不同区域,通过对各个区域的组织及相的分析,以及相应的拉伸及冲击试验研究了此类高强钢的组织和性能.结果表明,粗晶区的冲击性能最好,细晶区的冲击性能最低,为热影响区的薄弱环节.粗晶区组织为均匀粗细相间的板条贝氏体组织;在板条贝氏体上弥散析出碳化物;板条贝氏体界面上的奥氏体薄膜的存在是粗晶区韧性提高的原因.细晶区为孪晶马氏体+少量的板条马氏体,孪晶马氏体是导致细晶区性能下降的主要原因.

Abstract：

Microstructure and mechanical properties of HAZ of 980 MPa low carbon bainite high strength steel joints were studied . The different regions of welded joint HAZ were simulated by welding thermal simulation technique. Microstructure observation, phase analysis, and corresponding tensile and impact test for different regions of welded joint HAZ were taken. The results indicate: the impact property of coarse grain zone is the best, while the impact property of fine grain zone is the worst. So the fine grain zone is the weakest part of the welded joint. Microstructure of coarse grain zone is uniform interweaved coarse and fine lath martensites, and precipitation acicular ferrite are distributed between the lath martensites. Toughness of coarse grain zone is increased owing to the austenite thin film adherent lath martensite interface. Microstructure of fine grain zone are twin martensite and a small number of lath maarten-site, only minor acicular ferrite are distributed in the twin martensite . Toughness of fine-grained zone was decreased owing to twin martensite.     

两种规格超细晶粒钢的激光焊接

超细晶粒钢依靠微米级或亚微米级的铁素体,使钢的强度和韧性大大提高。本文分析了超细晶粒钢的焊接性及激光焊接的特点,进行了超细晶粒钢的激光焊接试验,并与等离子弧焊接、MAG焊接进行了比较,超细晶粒钢激光焊接接头粗晶区有较好的韧性,采用较小的激光功率并配合较慢的焊接速度,可减小粗晶区硬化倾向。终轧温度较高的SS400钢激光焊接接头强度高于母材,深度轧制钢激光焊接接头出现再结晶软化区,当软化区宽度较窄时,不影响整体接头强度,SS400钢和深度轧制钢激光焊接接头均有好的弯曲塑性。     

焊接电流对专用车厢体耐磨钢NM500钢板焊接接头组织性能的影响

针对专用车厢体耐磨钢NM500钢板焊接热影响区具有较高的淬硬性,焊接过程中易产生冷裂纹以及韧性下降等缺陷,当使用不同的焊接工艺时,其焊接接头性能相差较大的问题,对比分析了 240、280、320 A3种焊接电流对专用车厢体耐磨钢NM500钢板焊接接头力学性能和微观组织的影响规律.结果表明,随着焊接电流的增加,焊接软化区...     

厚板转子钢多层多道焊接头不同微区断裂韧度的分析

文中研究了厚板转子钢多层多道窄间隙焊接接头不同微区的断裂韧度,主要包括接头中热影响区粗晶区及细晶区,焊缝中的柱状晶区和等轴晶区.结果表明,焊缝内柱状晶区断裂韧度（J_m）最低,断裂韧度最小值为195 kJ/m2,而热影响区的细晶区断裂韧度最高,J_m为1 265 kJ/m2.热影响区细小的等轴晶粒（1~12 μm）和晶内均匀分布的碳化物是其断裂韧度较好的主要原因.焊缝内组织主要为回火索氏体,以柱状晶形式分布在焊缝中,裂纹容易沿柱状晶晶界扩展,导致焊缝的断裂韧度较低.整个接头柱状晶与等轴晶组织交替分布,提高抗裂纹扩展能力,保证了整个焊接接头的安全可靠.     

BWELDY960Q钢焊接热模拟热影响区组织与性能

采用焊接热模拟技术模拟BWELDY960Q钢焊接热影响区,在不同峰值温度条件下,研究热影响区各区域组织与性能的变化规律. 结果表明,热影响区各微区组织形态不同,粗晶区的组织为板条状马氏体,细晶区的组织为细晶板条马氏体,不完全重结晶区的组织为马氏体、索氏体和铁素体的混合组织,回火区组织为回火索氏体. 峰值温度达到1 200 ℃时,热影响区原始奥氏体晶粒已经开始粗化,并越接近熔合区,晶粒粗化现象越显著. 粗晶区冲击韧性较低,韧性损失为母材的82.17%,不完全重结晶区的冲击韧性损失为母材的46.53%. 模拟焊接热影响区组织比实际焊接热影响区组织更粗大.     

提高P91耐热钢焊接接头冲击韧度的研究

探讨了影响P91耐热钢焊接接头冲击韧度的工艺因素,对P91钢的常规焊接工艺进行调整,并模拟该工艺进行焊接试验。最后通过拉伸、弯曲、冲击试验、断口扫描和金相观察检验接头组织及性能。结果表明,在模拟焊接工艺下,P91耐热钢可以获得良好的焊接接头。焊缝拉伸强度高于母材;焊缝侧向弯曲试验外弧面未发现开裂;焊接接头的显微组织为回火板条马氏体,未出现非正常组织,焊缝晶粒明显细化;接头冲击韧度得到了大幅度提高。     

Characteristics of Laser Beam and Friction Stir Welded AISI 409M Ferritic Stainless Steel Joints

This article presents the comparative evaluation of microstructural features and mechanical properties of friction stir welded (solid-state) and laser beam welded (high energy density fusion welding) AISI 409M grade ferritic stainless steel joints. Optical microscopy, microhardness testing, transverse tensile, and impact tests were performed. The coarse ferrite grains in the base material were changed to fine grains consisting duplex structure of ferrite and martensite due to the rapid cooling rate and high strain induced by severe plastic deformation caused by frictional stirring. On the other hand, columnar dendritic grain structure was observed in fusion zone of laser beam welded joints. Tensile testing indicates overmatching of the weld metal relative to the base metal irrespective of the welding processes used. The LBW joint exhibited superior impact toughness compared to the FSW joint.     

G115钢CMT + P焊接工艺及组织和性能

基于冷金属过渡加脉冲(CMT + P)的焊接方法,研究了新型回火马氏体耐热钢G115的焊接性以及焊接接头组织和性能. 结果表明,焊接接头经热处理后为回火马氏体组织,焊缝晶粒呈现出等轴晶和柱状晶两种不同的形貌,而焊接热影响区和母材晶粒均为等轴晶. 与焊条电弧焊(SMAW)相比,CMT + P焊接方法有效降低了热输入,大幅度减小了热影响区宽度,提高了焊接接头的拉伸性能和热影响区冲击韧性,焊接接头焊缝冲击韧性略有降低. 焊接接头的室温和高温拉伸断裂机理均为韧性断裂,室温拉伸断口的韧窝内存在一定量的析出相.