共查询到19条相似文献,搜索用时 78 毫秒
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针对不同焊接参数下SQJ501型、SQJS07型和SQJ50MX型药芯焊丝电弧焊的熔滴过渡行为进行了拍照,并对焊接飞溅进行了测量,研究药芯焊丝电弧焊的熔滴过渡行为及其焊接飞溅的基本规律.试验结果表明:三种药芯焊丝随着焊接参数的增大,均依次发生短路过渡、大滴排斥过渡和细颗粒过渡.SQJ501型和SQJS0MX型药芯焊丝电孤焊电弧形态呈锥形,SQJS07型电弧形态接近于钟形.SQJ507型药芯焊丝出现细颗粒过渡的焊接参数比其他两种焊丝大.焊接工艺参数以及焊丝种类影响了熔滴过渡行为进而影响焊接飞溅,细颗粒过渡时产生的飞溅最小. 相似文献
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通过高速摄影技术及焊接飞溅率测试试验,详细阐述了金属粉型高铬铸铁自保护硬面药芯焊丝的熔滴过渡过程以及飞溅产生的原因及特点。结果表明,高铬铸铁自保护硬面药芯焊丝的熔滴过渡模式主要是大滴排斥过渡,熔滴可以长大到焊丝直径的2倍左右;其飞溅率较低,在1%左右;绝大部分飞溅产生于熔滴脱离焊丝端部瞬间、熔滴落入熔池的瞬间、熔滴爆炸以及熔滴形成的初期。其中,对焊接过程影响不大的直径小于1 mm的小颗粒飞溅占较大比例,存在少量的直径在1~2 mm之间的中等大小颗粒飞溅,而直径大于2 mm的大颗粒飞溅在试验中出现的频率较低。 相似文献
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采用高速摄影技术对金属粉芯型药芯焊丝的熔滴过渡及飞溅进行观察分析,总结了金属粉芯型药芯焊丝在试验参数下的熔滴过渡类型和特征以及飞溅类型和特征,阐述了熔滴过渡特征以及飞溅特征产生的原因.结果表明,采用100%CO2气体保护时,焊接过程中电弧电压波动较大,熔滴过渡不稳.以排斥过渡为主,少量细颗粒过渡和爆炸过渡,焊接飞溅大;采用5%CO2+95%Ar保护时,熔滴过渡为单一射滴过渡,熔滴过渡平稳,电弧稳定,焊接飞溅小;金属粉芯型药芯焊丝飞溅形式主要包括:气泡放出型飞溅、缩颈飞溅、熔滴爆炸飞溅以及电弧力引起的飞溅. 相似文献
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“滞熔”现象对碱性气保护药芯焊丝飞溅的影响 总被引:2,自引:0,他引:2
在大量工艺性试验的基础上,讨论了碱性气保护药芯焊丝特有的药芯滞熔现象及其对滴过渡形式的影响,并对药芯滞熔的因素(药芯填充率、矿物成分和金属粉)进行了正交试验,分析了探讨这些因素对药芯滞熔程度和飞溅的影响规律,提出控制芯滞熔程度是减小飞溅的有效5措施。 相似文献
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药芯焊丝电弧焊的熔滴过渡与相关技术特性 总被引:5,自引:0,他引:5
采用数码MOVIE照相技术,拍摄并电子记录了"O"形截面酸性渣系药芯焊丝电弧焊(FCAW)时的熔滴过渡行为,观察到不同工艺参数下的熔滴过渡类型有短路过渡、大颗粒过渡和细颗粒过渡;还观察到FCAW具有周向旋转、非轴向过渡、滞熔和熔滴/渣滴分离过渡等熔滴过渡特性.研究表明,药芯焊丝电弧的径向能量分布梯度小、能量密度分布较均匀,这导致了其焊缝形状系数较实芯焊丝CO2焊接增大80%以上. 相似文献
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基于计算机技术在焊接领域的应用现状,利用焊接电信号采集系统和光谱仪,基于Labview软件所设计的程序,实现同步采集,并把在每个时刻采集到的焊接电流,电弧电压波形信号及光谱仪采集到的光谱信息都在Labview的界面上同步显示,通过对两组药芯焊丝进行不同参数下熔化极气体保护焊药芯焊丝分析试验的同步采集,结合光谱信息、电信号及其前后时刻状态对药芯焊丝的典型熔滴过渡状态进行了分析。 相似文献
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《Science & Technology of Welding & Joining》2013,18(8):777-780
AbstractThe metal transfer behaviour of self-shielded flux cored wire and the resultant welding spatter were investigated by using a high speed camera. Three modes of metal transfer were found, i.e. bridging transfer without arc interruption in explosive form or by surface tension, globular repelled transfer and droplet transfer, while the former two modes played a key role in the weld metal transfer. Correspondingly, the bridge explosion, discontinuous globular repelled process and the misalignment of droplets transfer were the main factors causing the welding spatter. 相似文献
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Investigation on mechanism of fixing nitrogen in self-shielded flux cored arc welding 总被引:1,自引:0,他引:1
Prevention of nitrogen porosity in weld metal deposited with self-shielded flux cored wire with CaF_2-TiO_2-MgO slag system can be accomplished by using a "killing agent" such as titanium to react with nitrogen dissolved in the weld metal. The amount of titanium needed to prevent porosity is calculated thermodynamically for various dissolved nitrogen levels. Experimental flux cored wires are used to verify the thermodynamic model. It is concluded that approximately O.11 wt% titanium in the weld deposit is need to prevent nitrogen porosity when welding without externally applied shielding. 相似文献
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《Science & Technology of Welding & Joining》2013,18(3):139-148
AbstractFive experimental basic type flux cored arc welding consumable wire electrodes were manufactured from the same base formulation. The composition of these electrodes was adjusted in an attempt to improve the operating performance. This involved additions of various ratios of alkali oxides, namely, lithium, magnesium, sodium, and potassium containing ingredients, in the flux formulations. The operating behaviours of these experimental electrodes and two reference products (i.e. one commercial basic T–5 and one commercial rutile T–1 electrode) were thoroughly investigated by recording welding arc signals using a high speed data acquisition system. By comparing these electrodes among themselves, the experimental electrodes were reported to exhibit extremely stable arcs, some showing electrical arc signals even smoother than those for the reference rutile grade electrode. Despite their improved metal transfer consistency, however, basic electrodes were characterised by somewhat higher spatter levels. 相似文献
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焊接烟尘中含有大量有害物质,严重威胁到焊工的身体健康,所以针对焊接烟尘的研究具有十分重要的意义. 通过高速摄像采集系统研究了焊接时熔滴的过渡模式,通过焊接烟尘收集装置对焊接烟尘的发尘量进行测量,对不同工艺参数下产生的焊接烟尘进行了成分分析. 结果表明,在大的电参数下,熔滴过渡模式对烟尘的发尘量影响不大,但过大的热输入导致了熔滴、母材的蒸发量和焊接烟尘的增加,直流反接下,熔滴过渡主要表现为排斥过渡,出现较多的焊接飞溅颗粒,导致直流反接时的焊接烟尘增多. 不同的极性规范下,烟尘的元素类型基本一致. 由于在直流反接时,更多的低电离物质在熔滴底部燃烧蒸发,导致低电离物质元素含量相比于直流正接时较多. 而在直流正接时,阴极斑点总在氧化膜处进行燃烧,导致更多的氧化物元素蒸发,形成焊接烟尘. 因此,直流正接下氧化物元素含量比直流反接下的元素含量多. 相似文献
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Effect of oxygen-containing additives on weld penetration in self-shielded flux cored arc welding 下载免费PDF全文
The effect of Fe2O3 and Li2CO3 additives in flux core on the weld metal oxygen content and weld penetration in self-shielded flux cored arc welding were studied schematically. The result shows that the oxygen content in the weld metal and weld penetration both increased with the Fe2O3 addition increased in the range of 5wt.% to 20wt.% . The oxygen content in the weld metal was increased with the Li2CO3 addition increased in the range of 1wt.% to 8 wt.%. However, the weld penetration decreased when Li2CO3 addition exceeding 4 wt.%. High-speed photographic images show that when Fe2O3 addition in flux core exceeding 15wt.%, droplet became excessively large, so that spatters were frequently generated in large numbers. In this study, Fe2O3 and Li2CO3 in the amount of 11wt.% and 4wt.%, respectively, jointly added in the flux core can achieve a deeper weld penetration with sound usability characteristics. 相似文献