Pub Date : 2018-07-01DOI: 10.22486/IWJ/2018/V51/I3/175002
M. Saha, J. Mondal, Ajit Mondal, Santanu Das
Cladding is deposition of material on a corrosion-prone substrate to protect it from corrosion. Duplex stainless steel cladding is reported to have the ability to offer good corrosion resistance. In the present work, duplex stainless steel (E2209 T0-1) filler material is used for depositing a single layer with 50% overlap on E250 low alloy steel substrate using FCAW process with 100% CO as shielding gas. Three sets of heat input are chosen for the 2 experiment. Each set has different welding voltage and current, whereas travel speed has been kept constant for all experimental runs. Experiments have been replicated twice. 24-hour accelerated corrosion test is conducted on the clad surface in ferric chloride and hydrochloric acid solution. Results obtained from corrosion test indicate that all clad parts have better pitting corrosion resistance than the base metal. Corrosion resistance of clad parts exhibits decreasing tendency with greater heat input on the whole. Polynomial regression analysis is used to establish the quadratic relationship between heat input and pitting corrosion rate that indicate corrosion rate to increase with increase in heat input. ANOVA table depicts that the results obtained in pitting corrosion test against different heat input conditions are significant with high (95%) confidence level. The value of R2 (0.7014) indicates fairly good association between heat input and corrosion rate.
{"title":"Influence of Heat input on Corrosion Resistance of Duplex Stainless Steel Cladding using Flux Cored Arc Welding on Low Alloy Steel Flats","authors":"M. Saha, J. Mondal, Ajit Mondal, Santanu Das","doi":"10.22486/IWJ/2018/V51/I3/175002","DOIUrl":"https://doi.org/10.22486/IWJ/2018/V51/I3/175002","url":null,"abstract":"Cladding is deposition of material on a corrosion-prone substrate to protect it from corrosion. Duplex stainless steel cladding is reported to have the ability to offer good corrosion resistance. In the present work, duplex stainless steel (E2209 T0-1) filler material is used for depositing a single layer with 50% overlap on E250 low alloy steel substrate using FCAW process with 100% CO as shielding gas. Three sets of heat input are chosen for the 2 experiment. Each set has different welding voltage and current, whereas travel speed has been kept constant for all experimental runs. Experiments have been replicated twice. 24-hour accelerated corrosion test is conducted on the clad surface in ferric chloride and hydrochloric acid solution. Results obtained from corrosion test indicate that all clad parts have better pitting corrosion resistance than the base metal. Corrosion resistance of clad parts exhibits decreasing tendency with greater heat input on the whole. Polynomial regression analysis is used to establish the quadratic relationship between heat input and pitting corrosion rate that indicate corrosion rate to increase with increase in heat input. ANOVA table depicts that the results obtained in pitting corrosion test against different heat input conditions are significant with high (95%) confidence level. The value of R2 (0.7014) indicates fairly good association between heat input and corrosion rate.","PeriodicalId":393849,"journal":{"name":"Indian Welding Journal","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114728417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-07-01DOI: 10.22486/IWJ/2018/V51/I3/175003
A. K. Pathak, Chunduri Sree Harsha
Metallurgical and mechanical properties of a weldment depend on its cooling rate and temperature distribution during welding. Temperature distribution and cooling rate are responsible for formation of different microstructures and different size of grain in different zones. If cooling rate and temperature distribution can be predicted in advance it will help the design engineer at the design stage itself to design a good welded joint. Determination of cooling rate and temperature distribution in welding experimentally is very costly and time taking. In this work the cooling rate and temperature distribution was theoretically predicted using ANSYS14 and experimentally verified. For the theoretical thermal analysis, 3D modeling of thermal simulation of arc welding (MIG) process was done by using ANSYS14. The special feature of the analysis is the use of a fast iterative procedure during a single pass welding. Temperature dependent metal properties of AISI 430 were taken from standard data source and were utilized till to the liquid phase. Element shape '3-D 10-Node tetrahedral' (solid 87) was used in 3-D analysis. Conduction and convection are considered as heat transfer mode. The experimental values of welding speed, welding current, and arc voltage were used for theoretical analysis. Thermocouples were used to record welding temperature using data tracker and computer. Five thermocouples were fixed at the middle line of the plate to measure temperature distribution and cooling rate practically. Two plates of FSS were welded by MIG welding in butt joint position in single pass.
{"title":"Theoretical Thermal Model of MIG Welding of FSS (AISI 430) Using ANSYS and its Experimental Verification","authors":"A. K. Pathak, Chunduri Sree Harsha","doi":"10.22486/IWJ/2018/V51/I3/175003","DOIUrl":"https://doi.org/10.22486/IWJ/2018/V51/I3/175003","url":null,"abstract":"Metallurgical and mechanical properties of a weldment depend on its cooling rate and temperature distribution during welding. Temperature distribution and cooling rate are responsible for formation of different microstructures and different size of grain in different zones. If cooling rate and temperature distribution can be predicted in advance it will help the design engineer at the design stage itself to design a good welded joint. Determination of cooling rate and temperature distribution in welding experimentally is very costly and time taking. In this work the cooling rate and temperature distribution was theoretically predicted using ANSYS14 and experimentally verified. For the theoretical thermal analysis, 3D modeling of thermal simulation of arc welding (MIG) process was done by using ANSYS14. The special feature of the analysis is the use of a fast iterative procedure during a single pass welding. Temperature dependent metal properties of AISI 430 were taken from standard data source and were utilized till to the liquid phase. Element shape '3-D 10-Node tetrahedral' (solid 87) was used in 3-D analysis. Conduction and convection are considered as heat transfer mode. The experimental values of welding speed, welding current, and arc voltage were used for theoretical analysis. Thermocouples were used to record welding temperature using data tracker and computer. Five thermocouples were fixed at the middle line of the plate to measure temperature distribution and cooling rate practically. Two plates of FSS were welded by MIG welding in butt joint position in single pass.","PeriodicalId":393849,"journal":{"name":"Indian Welding Journal","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132658617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-07-01DOI: 10.22486/IWJ/2018/V51/I3/175007
S. Basak, T. Pal, M. Shome
MIG brazing is a potential process for joining coated automotive steel sheets over conventional fusion welding process such as gas metal arc welding (GMAW). However, understanding the process variables on the joint performance is not yet clear. This paper deals with details study on the effect of process parameters and two different modes of operation (push and pull) on bead geometry, microstructure, shear tensile strength and high cycle fatigue behavior of MIG brazed lap joint of 1.4 mm thick galvanized DP600 steel sheet using solid CuAl8 filler wire. It has been possible to obtain 98% joint efficiency due to dispersion hardening effect of fusion zone consisting of dispersed iron from base metal in copper matrix. Also, an interface region formed (~6 μm) inbetween fusion zone and steel substrate has been characterized. High cycle fatigue test of all MIG brazed joints showed fatigue endurance (2 million cycles) at 10% of tensile load and fatigue life increased with increasing heat input. Interestingly, three different fatigue failure paths were observed with different loading cycle, such as interfacial failure; fusion zone failure and fine grain heat affected zone failure where the bead geometry played an important role in brazed joint under dynamic loading condition.
{"title":"Shear Tensile and High Cycle Fatigue Performance of MIG Brazed DP600-GI Steel Sheet Joint","authors":"S. Basak, T. Pal, M. Shome","doi":"10.22486/IWJ/2018/V51/I3/175007","DOIUrl":"https://doi.org/10.22486/IWJ/2018/V51/I3/175007","url":null,"abstract":"MIG brazing is a potential process for joining coated automotive steel sheets over conventional fusion welding process such as gas metal arc welding (GMAW). However, understanding the process variables on the joint performance is not yet clear. This paper deals with details study on the effect of process parameters and two different modes of operation (push and pull) on bead geometry, microstructure, shear tensile strength and high cycle fatigue behavior of MIG brazed lap joint of 1.4 mm thick galvanized DP600 steel sheet using solid CuAl8 filler wire. It has been possible to obtain 98% joint efficiency due to dispersion hardening effect of fusion zone consisting of dispersed iron from base metal in copper matrix. Also, an interface region formed (~6 μm) inbetween fusion zone and steel substrate has been characterized. High cycle fatigue test of all MIG brazed joints showed fatigue endurance (2 million cycles) at 10% of tensile load and fatigue life increased with increasing heat input. Interestingly, three different fatigue failure paths were observed with different loading cycle, such as interfacial failure; fusion zone failure and fine grain heat affected zone failure where the bead geometry played an important role in brazed joint under dynamic loading condition.","PeriodicalId":393849,"journal":{"name":"Indian Welding Journal","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122164562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-07-01DOI: 10.22486/iwj.v51i3.175004
A. Paul, N. Chinoy, Banamali Das, S. Bhonsale
{"title":"Air-Cooled Induction Heating Solution for Heat Treatment of P91 Grade Steel in Welding Applications","authors":"A. Paul, N. Chinoy, Banamali Das, S. Bhonsale","doi":"10.22486/iwj.v51i3.175004","DOIUrl":"https://doi.org/10.22486/iwj.v51i3.175004","url":null,"abstract":"","PeriodicalId":393849,"journal":{"name":"Indian Welding Journal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115193393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-07-01DOI: 10.22486/IWJ/2018/V51/I3/175005
P. Ganesh, Abhay Kumar, S. Vishwakarma, A. Bose, R. Gupta, B. Sindal, S. Rai, P. C. Rao, P. R. Sankar, D. Nagpure, R. Kaul, G. Mundra, B. Singh
Superconducting radiofrequency (SRF) cavities would form important part of the proposed Indian Spallation Neutron Source and Accelerator Driven System. The high beta 650 MHz SRF cavity would be enclosed in a cylindrical vessel to hold liquid helium (LHe). Titanium (Ti) is being considered as the material of construction of helium vessel. The LHe inlet supply line and return helium gas pipe line of the helium vessel would be made of 316L stainless steel (SS). This requires a bi-metallic tubular transition joint between Ti and 316LSS, operating at LHe temperature. Vacuum brazing and explosive welding are potential processes for joining these two dissimilar metals, as fusion welding leads to extensive cracking. In the present experimental study, vacuum brazing was performed to join Ti-pipe/316LSS flange with BVAg8 braze filler metal (BFM). Notable features of the process include use of (i) 5-10 μm nickel electro-plating as a diffusion barrier on SS part for preventing possible iron migration towards titanium while improving surface wettability for BFM and (ii) use of 304 SS plug, shrunk fit into Ti-pipe, for achieving dimensional and profile accuracy of Ti-pipe during machining while also controlling joint gap during brazing process. The brazed joint displayed uniform joint thickness and acceptable level of hermeticity (helium leak rate 2 x 10-10mbar.lit/s) and also sustained six thermal cycles between 293 K and 77 K. Shear strength of Ti-SS brazed specimens, made in sandwich configuration, was found to be in the range of 50-60 MPa, with failure occurring at Ti/braze interface.
{"title":"Vacuum Brazing Of Titanium/316L Stainless Steel Transition Joint For Application In Helium Vessel Of Superconducting RF Cavities","authors":"P. Ganesh, Abhay Kumar, S. Vishwakarma, A. Bose, R. Gupta, B. Sindal, S. Rai, P. C. Rao, P. R. Sankar, D. Nagpure, R. Kaul, G. Mundra, B. Singh","doi":"10.22486/IWJ/2018/V51/I3/175005","DOIUrl":"https://doi.org/10.22486/IWJ/2018/V51/I3/175005","url":null,"abstract":"Superconducting radiofrequency (SRF) cavities would form important part of the proposed Indian Spallation Neutron Source and Accelerator Driven System. The high beta 650 MHz SRF cavity would be enclosed in a cylindrical vessel to hold liquid helium (LHe). Titanium (Ti) is being considered as the material of construction of helium vessel. The LHe inlet supply line and return helium gas pipe line of the helium vessel would be made of 316L stainless steel (SS). This requires a bi-metallic tubular transition joint between Ti and 316LSS, operating at LHe temperature. Vacuum brazing and explosive welding are potential processes for joining these two dissimilar metals, as fusion welding leads to extensive cracking. In the present experimental study, vacuum brazing was performed to join Ti-pipe/316LSS flange with BVAg8 braze filler metal (BFM). Notable features of the process include use of (i) 5-10 μm nickel electro-plating as a diffusion barrier on SS part for preventing possible iron migration towards titanium while improving surface wettability for BFM and (ii) use of 304 SS plug, shrunk fit into Ti-pipe, for achieving dimensional and profile accuracy of Ti-pipe during machining while also controlling joint gap during brazing process. The brazed joint displayed uniform joint thickness and acceptable level of hermeticity (helium leak rate 2 x 10-10mbar.lit/s) and also sustained six thermal cycles between 293 K and 77 K. Shear strength of Ti-SS brazed specimens, made in sandwich configuration, was found to be in the range of 50-60 MPa, with failure occurring at Ti/braze interface.","PeriodicalId":393849,"journal":{"name":"Indian Welding Journal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124442584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-07-01DOI: 10.22486/IWJ/2018/V51/I3/175006
A. Rao, Ayaskanta Singh, S. Parida, A. Kumar, V. Deshmukh
Friction stir welding (FSW) is known for joining low softening alloys metals such as aluminum, magnesium and copper, however joining of high softening alloys like steel, titanium and nickel base alloys is still a challenge due to tool material stringent property requirements and its availability. Presently, due to development new generation tool material FSW of high softening alloys is possible and also reported. FSW can effectively join different grade of low thickness steel, however the questions about joining thick section steel still remains a challenge. In this paper, FSW of 7 mm, 12 mm and 24 mm thick HSLA steel in single and double pass was carried out to develop the processing window for defect free weld joints and understanding the structure-property correlation. The increase in thickness of the base metal resulted in generation of higher load, higher heat input and consequently lower cooling rate. Therefore, the microstructure obtained after FSW in different thickness of steel also shows varying microstructures (grain boundary ferrite, acicular ferrite, widmensttan ferrite and upper bainite). Optical and scanning electron microscope (SEM) with electron back scattered diffraction (EBSD) detector was utilized to characterize the microstructure of FSW nugget zone. Tensile and hardness properties were also evaluated and correlated with the microstructure.
{"title":"Microstructure Evolution and Mechanical Properties of Friction Stir Welded Thick HSLA Steel","authors":"A. Rao, Ayaskanta Singh, S. Parida, A. Kumar, V. Deshmukh","doi":"10.22486/IWJ/2018/V51/I3/175006","DOIUrl":"https://doi.org/10.22486/IWJ/2018/V51/I3/175006","url":null,"abstract":"Friction stir welding (FSW) is known for joining low softening alloys metals such as aluminum, magnesium and copper, however joining of high softening alloys like steel, titanium and nickel base alloys is still a challenge due to tool material stringent property requirements and its availability. Presently, due to development new generation tool material FSW of high softening alloys is possible and also reported. FSW can effectively join different grade of low thickness steel, however the questions about joining thick section steel still remains a challenge. In this paper, FSW of 7 mm, 12 mm and 24 mm thick HSLA steel in single and double pass was carried out to develop the processing window for defect free weld joints and understanding the structure-property correlation. The increase in thickness of the base metal resulted in generation of higher load, higher heat input and consequently lower cooling rate. Therefore, the microstructure obtained after FSW in different thickness of steel also shows varying microstructures (grain boundary ferrite, acicular ferrite, widmensttan ferrite and upper bainite). Optical and scanning electron microscope (SEM) with electron back scattered diffraction (EBSD) detector was utilized to characterize the microstructure of FSW nugget zone. Tensile and hardness properties were also evaluated and correlated with the microstructure.","PeriodicalId":393849,"journal":{"name":"Indian Welding Journal","volume":"111 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114108646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.22486/IWJ.V52I1.178271
R. Santhosh, M. Aravind, M. Divya, A. Lakshminarayanan, S. Albert
A study on effect of cooling rate on mode of solidification and microstructure was carried out on austenitic stainless steel welds. A tube and plug of 316L stainless steel was joined using Gas Tungsten Arc Welding (GTAW) and laser welding processes. The welds were characterized using optical and Scanning Electron Microscope (SEM). The results indicate that cooling rate of the weld has significant effect on solidification mode, microstructure and solidification cracking. 316L weld joints prepared using GTAW process shows duplex microstructure of vermicular ferrite and austenite in the fusion zone. Whereas, the fusion zone of laser joint shows only single phase austenite microstructure. From these observations, it is clearly understood that the changes observed in the fusion zone microstructures of GTAW and laser welds are due to change in the mode of solidification as a result of change in the weld cooling rates. The predicted mode of solidification for GTA welds for 316L composition used in this study was Austenite-Ferrite (AF) and it was also confirmed through the microstructural observations. In laser joint, the weld has solidified in fully austenitic mode which deviates from the mode of solidification predicted by the conventional constitutional diagrams and hence modified weldability diagram was used. From this investigation, it was also found that the rapid solidification during laser welding is not completely partition less because segregation of sulphur was found using Scanning Electron Microscope – Energy Dispersive Spectroscope (SEM-EDS) along the dendrite boundaries of laser welds. High cooling rate during weld solidification which influences fully austenitic mode of solidification and micro segregation of impurities along the grain boundaries contribute to solidification cracking of welds in laser joints.
{"title":"Study on Effect of Weld Cooling Rate on Fusion Zone Microstructure and Solidification Cracks in 316L Austenitic Stainless Steel","authors":"R. Santhosh, M. Aravind, M. Divya, A. Lakshminarayanan, S. Albert","doi":"10.22486/IWJ.V52I1.178271","DOIUrl":"https://doi.org/10.22486/IWJ.V52I1.178271","url":null,"abstract":"A study on effect of cooling rate on mode of solidification and microstructure was carried out on austenitic stainless steel welds. A tube and plug of 316L stainless steel was joined using Gas Tungsten Arc Welding (GTAW) and laser welding processes. The welds were characterized using optical and Scanning Electron Microscope (SEM). The results indicate that cooling rate of the weld has significant effect on solidification mode, microstructure and solidification cracking. 316L weld joints prepared using GTAW process shows duplex microstructure of vermicular ferrite and austenite in the fusion zone. Whereas, the fusion zone of laser joint shows only single phase austenite microstructure. From these observations, it is clearly understood that the changes observed in the fusion zone microstructures of GTAW and laser welds are due to change in the mode of solidification as a result of change in the weld cooling rates. The predicted mode of solidification for GTA welds for 316L composition used in this study was Austenite-Ferrite (AF) and it was also confirmed through the microstructural observations. In laser joint, the weld has solidified in fully austenitic mode which deviates from the mode of solidification predicted by the conventional constitutional diagrams and hence modified weldability diagram was used. From this investigation, it was also found that the rapid solidification during laser welding is not completely partition less because segregation of sulphur was found using Scanning Electron Microscope – Energy Dispersive Spectroscope (SEM-EDS) along the dendrite boundaries of laser welds. High cooling rate during weld solidification which influences fully austenitic mode of solidification and micro segregation of impurities along the grain boundaries contribute to solidification cracking of welds in laser joints.","PeriodicalId":393849,"journal":{"name":"Indian Welding Journal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130379308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.22486/iwj.v52i1.178189
C. Shah, Ankur Mande, B. Rehani
Fusion welds of overlay were prepared between ferritic stainless steel of 410s with base metal of low alloy steel of SA 387 Gr. 11 Class 2 using Ni based consumables (Inconel 182 & 82) with GTAW & SMAW processes for clad restoration. For clad restoration, most of the process licensors indicate requirement of 3 mm undiluted clean chemistry throughout thickness as per ASME Sec. II, Part C to ensure sufficient corrosion resistant during operation of a coke drum. Experiments were carried out by varying different parameters that directly affect the dilution like chemical composition of filler wire, effect of bead height, overlap and layer by layer grinding for Inconel 182 electrode. For Inconel 82 filler wire, effect of wire feed rate and melting power on dilution control were studied. The dilution level of each weld fusion was determined through geometric measurements as well as through measuring chemical composition using optical emission spectrometer of the weld cross-sectional areas. Result states that reduction in electrode diameter plays a major role in reduction of dilution. Also, with increase in overlap, the weld metal chemistry tends to move towards filler metal chemistry. For GTAW process, filler metal feed rate & melting power individually do not contribute in reducing the effect of dilution however optimizing their combination yield required results. Also, effect of variation % Fe in weld overlay on corrosion resistance was examined using ASTM G 28 method A & for cyclic polarization with NaCl environment where rate of corrosion reduces drastically with reduction in dilution.
采用镍基耗材(Inconel 182和82)，采用GTAW和SMAW工艺，在410s铁素体不锈钢与SA 387 Gr. 11 Class 2低合金钢基体之间制备了覆盖层熔接焊缝。对于覆层修复，大多数工艺许可方都要求按照ASME第II节C部分的要求，在整个厚度上使用3mm未稀释的清洁化学物质，以确保在焦炭转鼓运行期间具有足够的耐腐蚀性。通过改变填料丝的化学成分、焊头高度、重叠和逐层磨削等直接影响Inconel 182电极稀释度的参数，进行了实验研究。针对Inconel 82填充丝，研究了送丝速度和熔化功率对稀释控制的影响。通过几何测量和利用焊接截面的光学发射光谱仪测量化学成分，确定了每次焊缝熔合的稀释程度。结果表明，电极直径的减小对稀释度的降低起主要作用。此外，随着重叠量的增加，焊缝金属化学倾向于向填充金属化学方向发展。对于GTAW工艺，填料金属进料速率和熔化功率单独对减少稀释效果没有贡献，但优化它们的组合可获得所需的结果。此外，采用ASTM G 28方法A &在NaCl环境下循环极化，在这种环境下，随着稀释度的减少，腐蚀速率急剧降低，测试了焊缝覆盖层中Fe变化对耐腐蚀性的影响。
{"title":"Dilution Control in SMAW & GTAW Welds Involving Low Alloy Steel, Ferritic Stainless Steels & Nickel Based Alloys","authors":"C. Shah, Ankur Mande, B. Rehani","doi":"10.22486/iwj.v52i1.178189","DOIUrl":"https://doi.org/10.22486/iwj.v52i1.178189","url":null,"abstract":"Fusion welds of overlay were prepared between ferritic stainless steel of 410s with base metal of low alloy steel of SA 387 Gr. 11 Class 2 using Ni based consumables (Inconel 182 & 82) with GTAW & SMAW processes for clad restoration. For clad restoration, most of the process licensors indicate requirement of 3 mm undiluted clean chemistry throughout thickness as per ASME Sec. II, Part C to ensure sufficient corrosion resistant during operation of a coke drum. Experiments were carried out by varying different parameters that directly affect the dilution like chemical composition of filler wire, effect of bead height, overlap and layer by layer grinding for Inconel 182 electrode. For Inconel 82 filler wire, effect of wire feed rate and melting power on dilution control were studied. The dilution level of each weld fusion was determined through geometric measurements as well as through measuring chemical composition using optical emission spectrometer of the weld cross-sectional areas. Result states that reduction in electrode diameter plays a major role in reduction of dilution. Also, with increase in overlap, the weld metal chemistry tends to move towards filler metal chemistry. For GTAW process, filler metal feed rate & melting power individually do not contribute in reducing the effect of dilution however optimizing their combination yield required results. Also, effect of variation % Fe in weld overlay on corrosion resistance was examined using ASTM G 28 method A & for cyclic polarization with NaCl environment where rate of corrosion reduces drastically with reduction in dilution.","PeriodicalId":393849,"journal":{"name":"Indian Welding Journal","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116719837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：