Niraj Kumar, Prakash Kumar, Ravi Shanker Vidyarthy, Chandan Pandey
{"title":"焊接过程中的微观结构演变对铬镍铁合金 718 和奥氏体不锈钢 304L 异种焊接接头机械性能和残余应力的影响","authors":"Niraj Kumar, Prakash Kumar, Ravi Shanker Vidyarthy, Chandan Pandey","doi":"10.1007/s11661-024-07571-w","DOIUrl":null,"url":null,"abstract":"<p>For this study, the researchers aimed to dissimilar weld the Nickel-based superalloy Inconel 718 (IN 718) with austenitic stainless steel 304L (ASS 304L) using the gas tungsten arc welding (GTAW) technique and Nickel-based filler IN 82 (ERNiCr-3). In order to examine the weld microstructures, we utilized optical microscopy (OM) and field emission scanning electron microscopy (FESEM) with energy-dispersive spectroscopy (EDS) to identify any segregation present in various weld zones. Through optical and FESEM analyses, it was revealed that the base metals (BM) exhibit an austenitic character. The IN 718 BM matrix contains dispersed <i>γ</i>′ and <i>γ</i>″ strengthening precipitates within the Nickel matrix. On the other hand, the ASS 304L BM displayed a unique austenitic microstructure characterized by twins features. The weld metal exhibited solidification grain boundaries (SGBs), migrated grain boundaries (MGBs), and distinct dendritic microstructures that had an impact on the properties of the weld. Through extensive analysis and mapping of the IN 82 weld zone, it was discovered that interdendritic regions contain carbides of Nb, Cr, and Ti. In addition, there were Unmixed zone (UZ) areas between the IN 82 filler and the base materials on both sides of the weld zone, appearing as islands and beaches. The texture of the different weld zones was evaluated using electron backscattered diffraction (EBSD) analysis. Additionally, the presence of a notable level of strain within the weld metal grains was observed through Kernel average misorientation (KAM) micrographs. Fractures were observed in the IN 82 weld zone, indicating that it is the weakest area in the IN 718/ASS 304L dissimilar weld at room temperature, according to the outputs of the tensile tests. The micro-hardness profile showed substantial hardness values in the weld zone, which can be attributed to the appearance of a diverse microstructure and additional precipitates. At room temperature, the recorded average tensile strength of the dissimilar weld joint was 626 MPa. In addition, experiments were carried out at high temperatures of 550 °C, 600 °C, and 650 °C to measure the tensile strength. In the high-temperature tensile tests, it was observed that the IN 82 weld zone exhibited higher tensile strength compared to the ASS 304L BM. Interestingly, the high temperatures tensile specimens failed in the 304L BM. The Charpy impact toughness test was performed with notches at ASS 304L HAZ, IN 718 HAZ, and the weld center. Using the deep hole drilling (DHD) technique, we were able to quantify residual stress and identify the location of the highest tensile residual stress, which was found to be 3 mm from the weld surface.</p>","PeriodicalId":18504,"journal":{"name":"Metallurgical and Materials Transactions A","volume":"54 1","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Role of Microstructure Evolution During Welding on Mechanical Properties and Residual Stresses of the Inconel 718 and Austenitic Stainless Steel 304L Dissimilar Weld Joint\",\"authors\":\"Niraj Kumar, Prakash Kumar, Ravi Shanker Vidyarthy, Chandan Pandey\",\"doi\":\"10.1007/s11661-024-07571-w\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>For this study, the researchers aimed to dissimilar weld the Nickel-based superalloy Inconel 718 (IN 718) with austenitic stainless steel 304L (ASS 304L) using the gas tungsten arc welding (GTAW) technique and Nickel-based filler IN 82 (ERNiCr-3). In order to examine the weld microstructures, we utilized optical microscopy (OM) and field emission scanning electron microscopy (FESEM) with energy-dispersive spectroscopy (EDS) to identify any segregation present in various weld zones. Through optical and FESEM analyses, it was revealed that the base metals (BM) exhibit an austenitic character. The IN 718 BM matrix contains dispersed <i>γ</i>′ and <i>γ</i>″ strengthening precipitates within the Nickel matrix. On the other hand, the ASS 304L BM displayed a unique austenitic microstructure characterized by twins features. The weld metal exhibited solidification grain boundaries (SGBs), migrated grain boundaries (MGBs), and distinct dendritic microstructures that had an impact on the properties of the weld. Through extensive analysis and mapping of the IN 82 weld zone, it was discovered that interdendritic regions contain carbides of Nb, Cr, and Ti. In addition, there were Unmixed zone (UZ) areas between the IN 82 filler and the base materials on both sides of the weld zone, appearing as islands and beaches. The texture of the different weld zones was evaluated using electron backscattered diffraction (EBSD) analysis. Additionally, the presence of a notable level of strain within the weld metal grains was observed through Kernel average misorientation (KAM) micrographs. Fractures were observed in the IN 82 weld zone, indicating that it is the weakest area in the IN 718/ASS 304L dissimilar weld at room temperature, according to the outputs of the tensile tests. The micro-hardness profile showed substantial hardness values in the weld zone, which can be attributed to the appearance of a diverse microstructure and additional precipitates. At room temperature, the recorded average tensile strength of the dissimilar weld joint was 626 MPa. In addition, experiments were carried out at high temperatures of 550 °C, 600 °C, and 650 °C to measure the tensile strength. In the high-temperature tensile tests, it was observed that the IN 82 weld zone exhibited higher tensile strength compared to the ASS 304L BM. Interestingly, the high temperatures tensile specimens failed in the 304L BM. The Charpy impact toughness test was performed with notches at ASS 304L HAZ, IN 718 HAZ, and the weld center. Using the deep hole drilling (DHD) technique, we were able to quantify residual stress and identify the location of the highest tensile residual stress, which was found to be 3 mm from the weld surface.</p>\",\"PeriodicalId\":18504,\"journal\":{\"name\":\"Metallurgical and Materials Transactions A\",\"volume\":\"54 1\",\"pages\":\"\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-09-11\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Metallurgical and Materials Transactions A\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1007/s11661-024-07571-w\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Metallurgical and Materials Transactions A","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1007/s11661-024-07571-w","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
摘要
在这项研究中,研究人员采用气体钨极氩弧焊(GTAW)技术和镍基填料 IN 82 (ERNiCr-3) 对镍基超级合金 Inconel 718 (IN 718) 和奥氏体不锈钢 304L (ASS 304L) 进行了异种焊接。为了检查焊缝的微观结构,我们使用了光学显微镜(OM)和场发射扫描电子显微镜(FESEM)以及能量色散光谱仪(EDS),以确定各焊接区是否存在偏析。通过光学和场发射扫描电子显微镜分析发现,基体金属 (BM) 具有奥氏体特性。IN 718 BM 基体在镍基体中含有分散的γ′和γ″强化沉淀。另一方面,ASS 304L BM 显示出独特的奥氏体微观结构,具有孪晶特征。焊接金属表现出凝固晶界(SGBs)、迁移晶界(MGBs)和独特的树枝状微观结构,这些都对焊缝的性能产生了影响。通过对 IN 82 焊接区进行大量分析和绘图,发现树枝状间区域含有 Nb、Cr 和 Ti 碳化物。此外,在 IN 82 填充物和焊接区两侧的母材之间还存在未混合区(UZ),表现为岛屿和海滩。利用电子反向散射衍射(EBSD)分析对不同焊接区的纹理进行了评估。此外,通过核平均错位(KAM)显微照片还观察到焊接金属晶粒内部存在明显的应变。根据拉伸试验的结果,在 IN 82 焊接区观察到了断裂,这表明它是 IN 718/ASS 304L 异种焊缝在室温下最薄弱的区域。显微硬度曲线显示焊接区的硬度值很高,这可能是由于出现了不同的显微结构和额外的析出物。在室温下,异种焊接接头的平均拉伸强度为 626 兆帕。此外,还在 550 ℃、600 ℃ 和 650 ℃ 的高温下进行了拉伸强度测量实验。在高温拉伸试验中观察到,与 ASS 304L BM 相比,IN 82 焊接区的拉伸强度更高。有趣的是,304L BM 的高温拉伸试样失败了。夏比冲击韧性测试在 ASS 304L 热影响区、IN 718 热影响区和焊接中心进行。我们使用深孔钻 (DHD) 技术量化了残余应力,并确定了拉伸残余应力最大的位置,发现该位置距离焊接表面 3 毫米。
Role of Microstructure Evolution During Welding on Mechanical Properties and Residual Stresses of the Inconel 718 and Austenitic Stainless Steel 304L Dissimilar Weld Joint
For this study, the researchers aimed to dissimilar weld the Nickel-based superalloy Inconel 718 (IN 718) with austenitic stainless steel 304L (ASS 304L) using the gas tungsten arc welding (GTAW) technique and Nickel-based filler IN 82 (ERNiCr-3). In order to examine the weld microstructures, we utilized optical microscopy (OM) and field emission scanning electron microscopy (FESEM) with energy-dispersive spectroscopy (EDS) to identify any segregation present in various weld zones. Through optical and FESEM analyses, it was revealed that the base metals (BM) exhibit an austenitic character. The IN 718 BM matrix contains dispersed γ′ and γ″ strengthening precipitates within the Nickel matrix. On the other hand, the ASS 304L BM displayed a unique austenitic microstructure characterized by twins features. The weld metal exhibited solidification grain boundaries (SGBs), migrated grain boundaries (MGBs), and distinct dendritic microstructures that had an impact on the properties of the weld. Through extensive analysis and mapping of the IN 82 weld zone, it was discovered that interdendritic regions contain carbides of Nb, Cr, and Ti. In addition, there were Unmixed zone (UZ) areas between the IN 82 filler and the base materials on both sides of the weld zone, appearing as islands and beaches. The texture of the different weld zones was evaluated using electron backscattered diffraction (EBSD) analysis. Additionally, the presence of a notable level of strain within the weld metal grains was observed through Kernel average misorientation (KAM) micrographs. Fractures were observed in the IN 82 weld zone, indicating that it is the weakest area in the IN 718/ASS 304L dissimilar weld at room temperature, according to the outputs of the tensile tests. The micro-hardness profile showed substantial hardness values in the weld zone, which can be attributed to the appearance of a diverse microstructure and additional precipitates. At room temperature, the recorded average tensile strength of the dissimilar weld joint was 626 MPa. In addition, experiments were carried out at high temperatures of 550 °C, 600 °C, and 650 °C to measure the tensile strength. In the high-temperature tensile tests, it was observed that the IN 82 weld zone exhibited higher tensile strength compared to the ASS 304L BM. Interestingly, the high temperatures tensile specimens failed in the 304L BM. The Charpy impact toughness test was performed with notches at ASS 304L HAZ, IN 718 HAZ, and the weld center. Using the deep hole drilling (DHD) technique, we were able to quantify residual stress and identify the location of the highest tensile residual stress, which was found to be 3 mm from the weld surface.