18MND5的焊接性能探讨

通过碳当量、冷裂纹敏感系数、热裂纹敏感系数和再热裂纹系数对18MND5进行了焊接性分析,采用埋弧焊和焊条电弧焊对18MND5进行焊接后,对焊接接头进行无损检测和力学性能试验,结果均满足标准和项目要求;并分析了焊接接头的显微组织,得到了理想的组织。试验结果表明,选用合理的措施和合适的焊接参数,采用埋弧焊和焊条电弧焊均能获得优异的焊接接头,并成功应用于产品焊接。     

15CrMoR钢板的焊接工艺研究

通过我公司制作的甲醇合成反应器产品,对80mm厚的15CrMoR钢板进行焊接工艺研究。焊接采用焊条电弧焊定位+双面埋弧自动焊,焊后进行热处理。热处理后对焊接接头进行力学性能试验,室温抗拉强度、350℃高温拉伸ReL、弯曲性能、冲击性能等指标均能很好的满足要求。     

搪玻璃设备应用CO2气体保护焊可行性的探讨

本文对CO_2气体保护焊焊接接头与焊条电弧焊、埋弧自动焊焊接接头的性能、可涂搪性进行了对比试验,并对CO_2气体保护焊和焊条电弧焊两种焊接方法的焊接费用作了比较,进行了搪玻璃设备上应用CO_2气体保护捍的可行性分析。     

关于00Crl9Nil0/15CrMoR复合钢板焊接工艺评定的论述

通过采用焊条电弧焊、埋弧焊、堆焊这三种焊接方法,对15CrMoR进行焊接工艺评定,确定复合钢板合理的焊接工艺,为设备的制造打下基础。     

耐热钢15CrMoR的焊接工艺研究

针对某公司的高压加氢反应器产品,对厚度为38mm的15CrMoR进行了焊接工艺评定。焊接方法采用钨极氩弧焊(GTAW)打底+焊条电弧焊(SMAW)填充盖面,焊后进行热处理。对焊接接头的拉伸强度、弯曲、冲击及硬度等性能进行了测试。测试结果表明,焊接接头的拉伸强度可达510 MPa以上,侧弯180°后未见裂纹产生;在-20℃的条件下,焊缝的冲击功可达46J以上,热影响区的冲击功可达42J以上;焊缝的平均硬度值为176HBW,热影响区的平均硬度值为190HBW。各项性能均可满足要求。     

SB409 N08810厚镍板的埋弧焊焊接工艺研究

分析了SB409 N08810镍板的焊接工艺。为提高效率,将厚镍板原采用的钨极惰性气体保护焊结合手工电弧焊焊接工艺改进为埋弧焊焊接工艺,并对镍板焊接接头的力学性能、弯曲性能和耐腐蚀性能进行了试验。试验结果表明,改进后的厚镍板埋弧焊焊接工艺可获得力学性能良好的对接接头,且焊接接头的耐腐蚀性能符合设计标准的要求。     

奥氏体不锈钢中厚板埋弧焊工艺优化

奥氏体不锈钢焊接的主要问题是焊接时易出热裂纹,焊接接头的晶间腐蚀倾向增大和焊缝金属的塑性韧性下降。解决的措施是,选用超低碳的或含钛、铌的焊接材料,并使焊缝金属成为奥氏体和少量铁素体的双相组织;埋弧焊时选用超低碳焊丝配烧结焊剂,多层多道焊,控制层间温度,加快焊接接头的冷却速度;以钨极氩弧焊打底取代碳弧气刨清根;中厚板焊接时应留足够大的组对间隙以防未焊透。通过焊接工艺评定,将优化后的埋弧焊工艺应用到中厚板不锈钢容器的焊接中,取得了满意的效果。     

L450/316L不锈钢复合钢管对焊缝焊接接头组织性能研究

对壁厚(10+2)mm的L450/316L复合管进行了对焊试验,打底焊及过渡焊采用管内外充氩保护的GTAW焊,填充及盖面焊采用手工电弧焊,并对其焊接接头进行拉伸、刻槽锤断、弯曲、冲击、晶间腐蚀试验评价对焊焊缝的性能,采用光学、扫描电镜(SEM)及能谱分析(EDS)对焊接接头的冲击断口、显微组织及合金元素的进行扩散分析。试验结果表明:接头力学性能良好,耐晶间腐蚀性能较好;焊缝不锈钢层主要有奥氏体、铁素体组成;过渡层组织较细小,可以防止不锈钢层金属中合金元素被扩散层稀释;扩散层组织主要为马氏体、少量的残余奥氏体;合金钢层组织为先共析铁素体、针状铁素体、粒状贝氏体和及少量珠光体。     

氨合成塔用2.25Cr-1Mo钢的焊接及热处理工艺研究

针对某公司的氨合成塔产品,通过采用厚度为50 mm的SA336 F22 CL3锻件进行了焊接工艺评定.采用埋弧自动焊焊接,通过选择合适的焊材、合理的焊接工艺参数及焊后热处理参数,对焊接接头的拉伸强度、弯曲、冲击等力学性能进行了测试,并对其焊缝及热影响区进行了回火脆化倾向评定试验.测试结果表明,焊接接头的各项力学能和回火...     

核电用SA-508 Gr.3 Cl.2钢带极电渣堆焊工艺

根据某核电项目要求,对堆焊要求的分析和堆焊方法的选择,通过带极电渣堆焊评定对堆焊金属进行拉伸、弯曲、化学成分、铁素体数、晶间腐蚀、硬度、金相的分析试验,结果满足标准和项目要求。试验结果表明,采用合理的措施和合适的焊接参数,使用电渣带极堆焊能获得优异焊接接头,并成功对产品的SA-508 Gr.3 Cl.2进行大面积不锈钢带极电渣堆焊。     

06Cr25Ni20焊接工艺研究

通过焊接材料的选择,焊接工艺的调整,对06Cr25Ni20不锈钢焊接热裂纹的防治进行了研究试验,最后得出了06Cr25Ni20应用SMAW、GTAW、SAW焊接方法的焊接工艺措施和焊接工艺参数.     

316L/15CrMoR复合板焊接接头腐蚀性能分析

本文通过晶间腐蚀试验和电化学腐蚀试验对不锈钢复合板焊接接头腐蚀性能进行分析。采用电化学工作站以及扫描电镜、XRD等技术手段对复合板焊接接头的性能、组织以及相组成等进行了检测。试验结果表明,焊条电弧焊接头出现裂纹,焊缝区铁素体含量18.3%,晶粒度9.5级,接头产生了σ等硬脆相;氩弧焊接头没有发现裂纹,自腐蚀电位为-0.464V,单位面积腐蚀电流2.6×10-6A。氩弧焊接头的耐腐蚀性能较好。     

预加氢反应器焊缝裂纹成因分析

无损检测发现预加氢反应器筒体环焊缝处存在多处埋藏裂纹。检测了反应器筒体基层(SA3 87Gr11C12 )和复层 (SA2 40TP3 2 1)材料的化学成分和力学性能 ;分析了反应器的热处理工艺参数和焊接工艺参数 ,计算了筒体材质的焊接裂纹敏感性指数 ;得出导致筒体焊缝开裂的主要因素是反应器高温回火保温时间不足、筒体材料的焊接裂纹敏感性指数较高、焊前预热温度偏低以及复合钢板过渡层焊接的复杂性。并提出了可供类似设备制造参考的热处理和焊接工艺参数     

16MnDR钢制低温压力容器焊接及热处理工艺研究

通过焊接材料的选择,焊接及热处理工艺的调整,对16MnDR钢制低温压力容器焊接及热处理工艺进行了研究试验,最后得出了该类设备应用SMAW、GTAW、SAW焊接方法的焊接及热处理工艺措施和工艺参数。     

Submerged friction stir weld of polyethylene sheets

The objective of this research work is to join polyethylene sheets using submerged friction stir welding by varying rotation speeds and traverse speeds. The effects of process parameters on macrostructure, microstructure, and mechanical property are investigated. The result indicates that the tensile strength increases at first and then decreases with the increase of rotation speed and traverse speed. The maximum tensile strength value of underwater welded joint is 12.3 MPa which is higher than normal weld joint. The microstructure of joint is investigated by using metallurgic microscope and laser scanning confocal microscope. The major microdefect of the interface is crack and air bubble. The result of differential scanning calorimetry which is used to measure the crystalline content of materials indirectly shows the crystalline content of parent material, heat affected zone, thermomechanically affected zone, and weld nugget approximate are 54.5%, 54.0% 51.1%, and 48.2%, respectively. The chief reasons of decrease in the tensile strength are formation of crack and air bubble and the decrease of crystalline content. The analysis of small angle X‐ray scattering indicates that the long period of weld regions decreases comparing parent material. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41059.     

Laser spot weld bonding of mild steel

Laser spot weld bonding (LSWB) is a new joining process, which combines laser spot welding with a layer of structural adhesive in a single joint. The purpose of this paper is to introduce a new LSWB process with a special pulsed laser. With this method, the impact of adhesive gas on molten pool is weakened, and the gas can exhaust from the gap of the metal sheets. The carbon decomposed from the adhesive diffuses into the molten pool and changes the microstructure of the weld joint. The joint is mainly composed of martensite and bainite, and twinned martensite is found in the interface between the adhesive layer and metal sheet. In tensile shear test, LSWB specimens give the highest energy absorption compared with laser spot welded samples and adhesive bonded samples.     

自动脉冲气保焊单面焊双面成形工艺的应用

介绍了自动脉冲气保焊的工艺特点,试验结果表明,自动脉冲气保焊单面焊双面成形工艺所焊制的接头性能能够满足压力容器和管道焊缝使用性能的要求;在压力管道和小规格的压力容器的焊接方面,自动脉冲气保焊单面焊双面成形工艺是传统的氩弧焊打底焊条电弧焊盖面工艺的比较理想的替代方法。     

Microwave welding of high density polyethylene using intrinsically conductive polyaniline

The use of intrinsically conductive polymers in welding of plastics and composites offers the possibility of developing new welding methods. Intrinsically conductive polyaniline (PANI) composite gaskets were used to microwave weld high density polyethylene (HDPE) bars. Two composite gaskets were made from a mixture of HDPE and PANI powders in different proportions. Adiabatic heating experiments were used to estimate the internal heat generation and electric field strength in the gasket. During welding, the effects of heating time, heating pressure and welding pressure were evaluated. It was found that increasing the heating time and the welding pressure increased the joint strength. The maximum tensile joint strength was achieved using a 60 wt% PANI gasket with a heating time of 60 sec and a welding pressure of 0.9 MPa; this resulted in a tensile weld strength of 24.79 ± 0.34 MPa, which equals the tensile strength of the bulk HDPE.