Welding of polymers is a useful assembly process that eliminates the need for adhesives or mechanical fasteners, saving consumable costs. One of the most common polymer welding processes is ultrasonic welding. Effective welding requires that the molten polymer chains at the joint surface diffuse across the joint and become entangled with polymer chains in the parts to be welded. This intermolecular diffusion and chain entanglement are the fundamental characteristics of welding. Using fundamental theories of heat generation and melt flow, optimal weld parameters can be calculated to ensure that diffusion across the weld joint occurs during ultrasonic welding.
{"title":"Prediction of Ultrasonic Welding Parameters for Polymer Joining","authors":"Miranda Marcus, Erol Sancaktar","doi":"10.29391/2024.103.027","DOIUrl":"https://doi.org/10.29391/2024.103.027","url":null,"abstract":"Welding of polymers is a useful assembly process that eliminates the need for adhesives or mechanical fasteners, saving consumable costs. One of the most common polymer welding processes is ultrasonic welding. Effective welding requires that the molten polymer chains at the joint surface diffuse across the joint and become entangled with polymer chains in the parts to be welded. This intermolecular diffusion and chain entanglement are the fundamental characteristics of welding. Using fundamental theories of heat generation and melt flow, optimal weld parameters can be calculated to ensure that diffusion across the weld joint occurs during ultrasonic welding.","PeriodicalId":23681,"journal":{"name":"Welding Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141711253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Understanding the controlling mechanisms of γ columnar grain size in the weld metal of low-carbon, low-alloy steel is critical for optimizing resultant microstructures and the weld metal’s ensuing properties. Here, we investigate the role of welding flux composition upon the γ columnar grain size by submerged arc welding of EH36 shipbuilding steel with designed CaF2-SiO2 fluxes. We found that the addition of SiO2 from 5 to 40 mass-% increases average columnar grain size by a factor of nearly 2.5, which results from the change of the weld pool solidification mode from peritectic to primary δ solidification. Such a change is directly related to element transfer behaviors between the flux and the weld metal. Furthermore, we offer compelling evidence that alterations in γ columnar grain size are not primarily governed by significantly populated inclusions and/or weld metal macro-morphological changes. Our findings may largely serve as a viable strategy toward designing welding consumables to match base metals to ensure the soundness of the weldment.
{"title":"SiO2-bearing Fluxes Induced Evolution of γ Columnar Grain Size","authors":"Chao Han, Ming Zhong, Peng Zuo, Cong Wang","doi":"10.29391/2024.103.031","DOIUrl":"https://doi.org/10.29391/2024.103.031","url":null,"abstract":"Understanding the controlling mechanisms of γ columnar grain size in the weld metal of low-carbon, low-alloy steel is critical for optimizing resultant microstructures and the weld metal’s ensuing properties. Here, we investigate the role of welding flux composition upon the γ columnar grain size by submerged arc welding of EH36 shipbuilding steel with designed CaF2-SiO2 fluxes. We found that the addition of SiO2 from 5 to 40 mass-% increases average columnar grain size by a factor of nearly 2.5, which results from the change of the weld pool solidification mode from peritectic to primary δ solidification. Such a change is directly related to element transfer behaviors between the flux and the weld metal. Furthermore, we offer compelling evidence that alterations in γ columnar grain size are not primarily governed by significantly populated inclusions and/or weld metal macro-morphological changes. Our findings may largely serve as a viable strategy toward designing welding consumables to match base metals to ensure the soundness of the weldment.","PeriodicalId":23681,"journal":{"name":"Welding Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141707777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hanwen Yang, Nazmul Huda, X. Zhao, A. Gerlich, James Chen
In Part 1 of this study, the influences of feed rate and preheat of the wire on the fusion zone microstructure of X80 steel laser root welds were investigated. Part 2 of this study reveals the effect of cold versus hot wire feed on mechanical properties. Although strength overmatching with the X80 base metal was maintained, the wire alloying elements reduced the hardness of the upper region of the laser fusion zone but had limited effect on the bottom of the fusion zone due to the incomplete mixing of the filler material with the base metal in the bottom root region of the joint. The addition of ER70S-6 filler wire improved the impact toughness of the weld metal at 0°C, due to the formation of an acicular ferrite microstructure. As the temperature decreased to –20°C (–4°F) and –45°C (–49°F), ductile to brittle transition occurred, leading to lower weld metal toughness.
{"title":"Effect of Wire Preheat and Feed Rate in X80 Steel Laser Root Welds: Part 2 — Mechanical Properties","authors":"Hanwen Yang, Nazmul Huda, X. Zhao, A. Gerlich, James Chen","doi":"10.29391/2024.103.010","DOIUrl":"https://doi.org/10.29391/2024.103.010","url":null,"abstract":"In Part 1 of this study, the influences of feed rate and preheat of the wire on the fusion zone microstructure of X80 steel laser root welds were investigated. Part 2 of this study reveals the effect of cold versus hot wire feed on mechanical properties. Although strength overmatching with the X80 base metal was maintained, the wire alloying elements reduced the hardness of the upper region of the laser fusion zone but had limited effect on the bottom of the fusion zone due to the incomplete mixing of the filler material with the base metal in the bottom root region of the joint. The addition of ER70S-6 filler wire improved the impact toughness of the weld metal at 0°C, due to the formation of an acicular ferrite microstructure. As the temperature decreased to –20°C (–4°F) and –45°C (–49°F), ductile to brittle transition occurred, leading to lower weld metal toughness.","PeriodicalId":23681,"journal":{"name":"Welding Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140357256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hanwen Yang, Nazmul Huda, X. Zhao, A. Gerlich, James Chen
Laser welding with cold versus hot wire feed was employed as a root pass to weld X80 pipeline steel. The influences of wire feed rate and preheat on the fusion zone microstructure were investigated. Increasing the wire feed rate helped generate acicular ferrite in the weld metal, and preheating the wire further suppressed the formation of bainite. The acicular ferrite in the upper region of the fusion zone was finer than that in the lower region, which was due to an increase in nucleation sites available. Five fill and cap passes were applied by gas metal arc welding to fill the remaining top part of the groove. Compared to arc welding with a higher heat input, laser welding led to finer prior austenite grains and smaller bainite packet size in the coarse-grained heat-affected zone and limited the formation of martensite-austenite constituents in the intercritically reheated coarse-grained heat-affected zone.
{"title":"Effect of Wire Preheat and Feed Rate in X80 Steel Laser Root Welds: Part 1 — Microstructure","authors":"Hanwen Yang, Nazmul Huda, X. Zhao, A. Gerlich, James Chen","doi":"10.29391/2024.103.009","DOIUrl":"https://doi.org/10.29391/2024.103.009","url":null,"abstract":"Laser welding with cold versus hot wire feed was employed as a root pass to weld X80 pipeline steel. The influences of wire feed rate and preheat on the fusion zone microstructure were investigated. Increasing the wire feed rate helped generate acicular ferrite in the weld metal, and preheating the wire further suppressed the formation of bainite. The acicular ferrite in the upper region of the fusion zone was finer than that in the lower region, which was due to an increase in nucleation sites available. Five fill and cap passes were applied by gas metal arc welding to fill the remaining top part of the groove. Compared to arc welding with a higher heat input, laser welding led to finer prior austenite grains and smaller bainite packet size in the coarse-grained heat-affected zone and limited the formation of martensite-austenite constituents in the intercritically reheated coarse-grained heat-affected zone.","PeriodicalId":23681,"journal":{"name":"Welding Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140355857","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abdul Sayeed Khan, Pingsha Dong, Fengchao Liu, Yuning Zhang
Structural lightweighting through the effective use of multiple materials has received increasing attention for fulfilling today’s demands for environmental sustainability in transportation systems. Direct dissimilar material joining methods (versus, e.g., traditional adhesive bonding or mechanical fastening) have become increasingly desirable since they offer process simplicity, production efficiency, and hermetic sealing, among others. In this two-part article, we provide a critical assessment of the state-of-the-art research and promising direct dissimilar material joining techniques reported over the last decades, with a particular emphasis on their potential for structural applications in Part I. As such, recent advances in advanced joint design and modeling methods for enabling optimum joint design for jointability and joint performance are presented along with some detailed examples for demonstrating their potential impacts on industrial applications in Part II. Finally, recommendations on future research and development directions are outlined for supporting the industry’s drive towards multi-material lightweighting.
{"title":"A State-of-the-Art Review on Direct Welding of Polymer to Metal for Structural Applications: Part 1 — Promising Processes","authors":"Abdul Sayeed Khan, Pingsha Dong, Fengchao Liu, Yuning Zhang","doi":"10.29391/2024.103.011","DOIUrl":"https://doi.org/10.29391/2024.103.011","url":null,"abstract":"Structural lightweighting through the effective use of multiple materials has received increasing attention for fulfilling today’s demands for environmental sustainability in transportation systems. Direct dissimilar material joining methods (versus, e.g., traditional adhesive bonding or mechanical fastening) have become increasingly desirable since they offer process simplicity, production efficiency, and hermetic sealing, among others. In this two-part article, we provide a critical assessment of the state-of-the-art research and promising direct dissimilar material joining techniques reported over the last decades, with a particular emphasis on their potential for structural applications in Part I. As such, recent advances in advanced joint design and modeling methods for enabling optimum joint design for jointability and joint performance are presented along with some detailed examples for demonstrating their potential impacts on industrial applications in Part II. Finally, recommendations on future research and development directions are outlined for supporting the industry’s drive towards multi-material lightweighting.","PeriodicalId":23681,"journal":{"name":"Welding Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140356564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sensing, modeling, and control are the key technologies of intelligent welding manufacturing. The position and attitude of the welding torch relative to the weld seam affects the quality of the produced weld directly, which is the basis of control and offline programming of the welding robot. Based on the existing research of reversed electrode image (REI) on monitoring of weld pool surface and penetration state, this work focused on the application of REI on monitoring of welding torch position and attitude (TPA). In this paper, a REI-TPA model was established to quantitively relate REI to TPA by considering the surface of the weld pool as a spherical mirror. With the REI-TPA model, the offset distance and deflection angle of the welding torch relative to the correct position and attitude can be calculated. The calculation is based on the measurement of the relative distance between the tip of REI and the electrode in a passive visual image of the weld pool, arc length, and weld pool geometry. This model can be applied to the real-time control of TPA, which is a supplement to the application of welding passive visual image and an extension to multi-information acquisition and processing methods in the robotic welding process.
传感、建模和控制是智能焊接制造的关键技术。焊枪相对于焊缝的位置和姿态直接影响焊缝的质量，是焊接机器人控制和离线编程的基础。在已有的反向电极图像（REI）监测焊池表面和熔透状态的研究基础上，本研究重点关注 REI 在监测焊枪位置和姿态（TPA）方面的应用。本文建立了 REI-TPA 模型，通过将焊池表面视为球面镜，将 REI 与 TPA 定量联系起来。利用 REI-TPA 模型，可以计算出焊枪相对于正确位置和姿态的偏移距离和偏转角度。计算的基础是在焊池、电弧长度和焊池几何形状的被动视觉图像中测量 REI 尖端与电极之间的相对距离。该模型可应用于 TPA 的实时控制，是焊接被动视觉图像应用的补充，也是机器人焊接过程中多信息采集和处理方法的延伸。
{"title":"Monitoring Welding Torch Position and Posture Using Reversed Electrode Images – Part I: Establishment of the REI-TPA Model","authors":"YU Fu, Shanben Chen, Zongyao Chen","doi":"10.29391/2024.103.019","DOIUrl":"https://doi.org/10.29391/2024.103.019","url":null,"abstract":"Sensing, modeling, and control are the key technologies of intelligent welding manufacturing. The position and attitude of the welding torch relative to the weld seam affects the quality of the produced weld directly, which is the basis of control and offline programming of the welding robot. Based on the existing research of reversed electrode image (REI) on monitoring of weld pool surface and penetration state, this work focused on the application of REI on monitoring of welding torch position and attitude (TPA). In this paper, a REI-TPA model was established to quantitively relate REI to TPA by considering the surface of the weld pool as a spherical mirror. With the REI-TPA model, the offset distance and deflection angle of the welding torch relative to the correct position and attitude can be calculated. The calculation is based on the measurement of the relative distance between the tip of REI and the electrode in a passive visual image of the weld pool, arc length, and weld pool geometry. This model can be applied to the real-time control of TPA, which is a supplement to the application of welding passive visual image and an extension to multi-information acquisition and processing methods in the robotic welding process.","PeriodicalId":23681,"journal":{"name":"Welding Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140402280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zi-jue Tang, Huihui Yang, Le Wan, Pengyuan Ren, Xiaolin Zhang, Yi Wu, Haowei Wang, Hongze Wang
Joining Cu-Al with 0.6 mm is important for the high-power density battery in the new energy field. Low laser absorptivity is a challenge in Cu-Al welding with conventional infrared laser at around 1000 nm wavelength, where keyhole welding is necessary. It is difficult to control welding qualities in keyhole welding due to the intense flow and violently changing absorption rate. At 450 nm wavelength, Cu and Al have high laser absorptizzvity which has the potential to implement stable conduction welding. Therefore, this work adopted a blue laser welding system, and for the first time, realized the conduction welding of 0.6 mm Cu and 0.6 mm Al sheets. The welding process, surface appearance, mechanical properties, and electrical properties were investigated. The results showed that high-power (1950 W) could effectively realize stable Cu-Al conduction welding without spatters, and the welding speed could reach 40 mm/s. Compared with an infrared laser, the blue laser could weld Cu-Al using the form of Cu on top and Al on bottom, which was beneficial for a wide process window and stable welding process. A larger bead width and more consistent intermetallic compound thickness resulting from the blue laser were conducive to performance improvement. In addition, the relationship between welding parameters, molten pool characteristics, and process qualities was built. It provided a possibility to control the welding quality under the influence of strong heat accumulation and high thermal conductivity. This work demonstrated that blue laser has great potential in joining Cu-Al for new energy applications.
{"title":"Blue Laser Conduction Welding of Dissimilar Cu and Al Sheets","authors":"Zi-jue Tang, Huihui Yang, Le Wan, Pengyuan Ren, Xiaolin Zhang, Yi Wu, Haowei Wang, Hongze Wang","doi":"10.29391/2024.103.018","DOIUrl":"https://doi.org/10.29391/2024.103.018","url":null,"abstract":"Joining Cu-Al with 0.6 mm is important for the high-power density battery in the new energy field. Low laser absorptivity is a challenge in Cu-Al welding with conventional infrared laser at around 1000 nm wavelength, where keyhole welding is necessary. It is difficult to control welding qualities in keyhole welding due to the intense flow and violently changing absorption rate. At 450 nm wavelength, Cu and Al have high laser absorptizzvity which has the potential to implement stable conduction welding. Therefore, this work adopted a blue laser welding system, and for the first time, realized the conduction welding of 0.6 mm Cu and 0.6 mm Al sheets. The welding process, surface appearance, mechanical properties, and electrical properties were investigated. The results showed that high-power (1950 W) could effectively realize stable Cu-Al conduction welding without spatters, and the welding speed could reach 40 mm/s. Compared with an infrared laser, the blue laser could weld Cu-Al using the form of Cu on top and Al on bottom, which was beneficial for a wide process window and stable welding process. A larger bead width and more consistent intermetallic compound thickness resulting from the blue laser were conducive to performance improvement. In addition, the relationship between welding parameters, molten pool characteristics, and process qualities was built. It provided a possibility to control the welding quality under the influence of strong heat accumulation and high thermal conductivity. This work demonstrated that blue laser has great potential in joining Cu-Al for new energy applications.","PeriodicalId":23681,"journal":{"name":"Welding Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140276006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The first half of this paper reviews the significant body of work that has been devoted to understanding the fundamentals of the basic GMAW process and the use of this knowledge to develop and enhance process performance. Some of the important background studies devoted to metal transfer mechanisms are reviewed, and the tools developed to model the process and define the critical control variables for GMAW are discussed. The limitations in process performance, such as unstable transfer in low current globular, spray, and short circuit transfer modes and the perceived risk of lack of fusion in short circuit transfer, are considered. These limitations have been mitigated to some extent by process optimization based on the process models developed as well as improvements in welding consumables. Despite the limitations, it is suggested that satisfactory operation could be achieved with simple equipment and a limited number of essential control variables. Early attempts to rectify the limitations are described, but it is argued that these early innovations were restricted by the limited operating envelopes and capabilities of the original power supplies. The radical development of advanced electronic power control and its effect on extending the process operating modes is described, as are the developments in dynamic waveform control. The introduction of synergic control to enable the more complex control variables to be accommodated is also discussed. The effect of waveform control and synergic program constraints on welding procedure management is analyzed, and the advantages of improved process monitoring are reviewed. Future developments in process monitoring and control based on artificial intelligence are introduced, and a possible development to improve synergic program flexibility is suggested. Finally, the type of applications that fully utilize this ‘intelligent’ GMAW are illustrated.
{"title":"Evolution of Advanced Process Control in GMAW: Innovations, Implications, and Application","authors":"John Norrish","doi":"10.29391/2024.103.015","DOIUrl":"https://doi.org/10.29391/2024.103.015","url":null,"abstract":"The first half of this paper reviews the significant body of work that has been devoted to understanding the fundamentals of the basic GMAW process and the use of this knowledge to develop and enhance process performance. Some of the important background studies devoted to metal transfer mechanisms are reviewed, and the tools developed to model the process and define the critical control variables for GMAW are discussed. The limitations in process performance, such as unstable transfer in low current globular, spray, and short circuit transfer modes and the perceived risk of lack of fusion in short circuit transfer, are considered. These limitations have been mitigated to some extent by process optimization based on the process models developed as well as improvements in welding consumables. Despite the limitations, it is suggested that satisfactory operation could be achieved with simple equipment and a limited number of essential control variables. Early attempts to rectify the limitations are described, but it is argued that these early innovations were restricted by the limited operating envelopes and capabilities of the original power supplies. The radical development of advanced electronic power control and its effect on extending the process operating modes is described, as are the developments in dynamic waveform control. The introduction of synergic control to enable the more complex control variables to be accommodated is also discussed. The effect of waveform control and synergic program constraints on welding procedure management is analyzed, and the advantages of improved process monitoring are reviewed. Future developments in process monitoring and control based on artificial intelligence are introduced, and a possible development to improve synergic program flexibility is suggested. Finally, the type of applications that fully utilize this ‘intelligent’ GMAW are illustrated.","PeriodicalId":23681,"journal":{"name":"Welding Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140276051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kopparthi Ravikiran, Leijun Li, Suvan Dev Choudhury, N. Saini, NITIN KUMAR SHARMA, Neil Anderson, Y. Wang, Muhammad Rashid
The effect of postweld heat treatment (PWHT) on Charpy V-notch impact toughness of a highfrequency electric-resistance welded (HF-ERW) grade X70 pipeline steel is investigated. PWHT thermal cycles are simulated using the Gleeble on the as-welded specimens. Microstructure, along with crystallographic texture and microhardness, is characterized in specimens that are impact tested at –5°C (23°F), –30°C (–22°F), and –45°C (–49°F). The impact toughness values show a wide scatter band and decrease with the increasing peak temperature of the PWHT. For higher peak temperatures, the microstructure of the heat-affected zone (HAZ) gradually changed from equiaxed ferrite to bainitic ferrite. Furthermore, the prior austenite grain size (PAGS) increases with the increasing peak temperature. The density of high-angle grain boundaries decreases, and the fraction of cleavage planes {100} parallel to the impact fracture plane increases for higher peak temperatures of the PWHT.
{"title":"Postweld Heat Treatment on Toughness of Electric- Resistance Welded X70 Steel","authors":"Kopparthi Ravikiran, Leijun Li, Suvan Dev Choudhury, N. Saini, NITIN KUMAR SHARMA, Neil Anderson, Y. Wang, Muhammad Rashid","doi":"10.29391/2024.103.017","DOIUrl":"https://doi.org/10.29391/2024.103.017","url":null,"abstract":"The effect of postweld heat treatment (PWHT) on Charpy V-notch impact toughness of a highfrequency electric-resistance welded (HF-ERW) grade X70 pipeline steel is investigated. PWHT thermal cycles are simulated using the Gleeble on the as-welded specimens. Microstructure, along with crystallographic texture and microhardness, is characterized in specimens that are impact tested at –5°C (23°F), –30°C (–22°F), and –45°C (–49°F). The impact toughness values show a wide scatter band and decrease with the increasing peak temperature of the PWHT. For higher peak temperatures, the microstructure of the heat-affected zone (HAZ) gradually changed from equiaxed ferrite to bainitic ferrite. Furthermore, the prior austenite grain size (PAGS) increases with the increasing peak temperature. The density of high-angle grain boundaries decreases, and the fraction of cleavage planes {100} parallel to the impact fracture plane increases for higher peak temperatures of the PWHT.","PeriodicalId":23681,"journal":{"name":"Welding Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140278493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
There has been a steady rise in the use of computational tools to model or describe weld microstructure and properties from data sets containing a wide range of inputs and outputs measured by experiments. The tools range in sophistication from simple two-factor correlations in spreadsheets to artificial neural networks.
{"title":"Comments on the Numerical Models for Correlating Weld Metal Composition to Microstructure and Properties","authors":"Glyn Evans, Marie Quintana, S. S. Babu","doi":"10.29391/2024.103.012","DOIUrl":"https://doi.org/10.29391/2024.103.012","url":null,"abstract":"There has been a steady rise in the use of computational tools to model or describe weld microstructure and properties from data sets containing a wide range of inputs and outputs measured by experiments. The tools range in sophistication from simple two-factor correlations in spreadsheets to artificial neural networks.","PeriodicalId":23681,"journal":{"name":"Welding Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140464613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","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：