ProgramMaster Logo
Conference Tools for 2022 AWS Professional Program
Register as a New User
Submit An Abstract
Propose A Symposium
Presenter/Author Tools
Organizer/Editor Tools
About this Abstract
Meeting 2022 AWS Professional Program
Symposium 2022 AWS Professional Program
Presentation Title Influence of Microstructure on the Mechanism of Hydrogen-assisted Cracking in Dissimilar Metal Welds for Refinery Application
Author(s) Abbas Mohammadi, Jorge Penso, Boian Alexandrov
On-Site Speaker (Planned) Abbas Mohammadi
Abstract Scope Introduction: Dissimilar metal welds (DMWs) are extensively used in power generation, heavy fabrication industries and the oil, gas, and petrochemical industries. It is well-known that hydrogen deteriorates mechanical properties of metals and alloys during their service by the phenomenon of hydrogen embrittlement. Hydrogen cracking is the most significant mechanism of failure in many welded components often resulting in a failure below the design limits. Examples of catastrophic failures of DMWs in subsea service under cathodic protection and in petrochemical applications highlight the importance of further investigations on the role of hydrogen in the failure mechanism of welded components. Hydrogen embrittlement is related to the interaction of hydrogen with microstructural features and defects such as dislocations, precipitates, segregations, grain boundaries and cracks. Microstructural features in the vicinity of the fusion boundary in DMWs significantly influence the susceptibility to local hydrogen-assisted cracking. Despite extensive reports on the microstructures-hydrogen interactions, there is a lack of understanding of hydrogen-assisted cracking mechanisms in DMWs. In this study, we attempt to investigate the susceptibility to hydrogen embrittlement of two types of subsea DMWs of nickel-based filler metals on low alloy steel substrate. Experimental procedure: DMW#1 was made of 25.4 mm thick F22 steel pipes internally clad with 6 mm layer of Alloy 825 and welded in a V-groove configuration. The first 4 passes were performed with GTAW process using FM82 2.4 mm diameter filler wire. The remaining 30 passes were performed with SMAW using Alloy 182 3.2 mm diameter shielded electrodes. The DMW was subjected to a 4-hour PWHT at 720oC. DMW#2 was made of 21.95 mm thick carbon steel pipes internally clad with 3 mm layer of Alloy 825 and welded in a V-groove configuration. The first 3 passes were performed with GTAW process using FM82 1.6 mm diameter filler wire. The remaining 25 passes were performed with SMAW using Alloy 182 3.2 mm diameter shielded electrodes. The DMW was subjected to a 1-hour PWHT at 610oC. Smooth specimens are cut from welded pipes containing fusion boundary in the center of the gauge section using electrical discharge machining (EDM). The DMW microstructures are characterized using optical microscope (OM), scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD). The Dissimilar fusion boundary is subjected to the delayed hydrogen cracking test (DHCT) using a constant tensile load testing (CTLT) method. In this method, the sample is held at the constant tensile load corresponding to 0.9 yield strength of the base metal. The sample is placed at the center of a platinum wire coil used as the anode. Hydrogen is introduced into the sample by electrochemical charging in a 0.1N H2SO4 and 0.1g/l Na2S2O3 aqueous solution with a pH of 1.20.1 at a current density of 10 mA/cm2 at room temperature. The solution is continuously circulated through the test cell and pH is monitored throughout testing to ensure consistent charging. Then, fracture surfaces of failed specimens are observed using SEM. Results / Discussion: To evaluate the susceptibility of DMWs to hydrogen cracking, the test results, in terms of time to failure, sustained mechanical energy and sustained displacement are evaluated. The sustained mechanical energy and the sustained displacement are determined by multiplying the applied load with the total displacement at the time of failure, and by integrating the displacement vs. time curve, respectively. The post-mortem microstructural characterization and fracture surface illustrate the influence of microstructural features in the vicinity of the fusion boundary on hydrogen-assisted crack initiation and propagation and develop the mechanisms of hydrogen-related failure. This research is still ongoing and additional investigations are planned for the susceptibility of DMWs to hydrogen-assisted failure and microstructural characterization. Further results and discussions will be provided as soon as experiments and observations have been finished. Conclusion: It is expected that the microstructure in the fusion boundary region plays a crucial role on the hydrogen-assisted cracking susceptibility in the tested DMWs. The final conclusions will be added after evaluating the results of the ongoing experiments and metallurgical characterization.
Proceedings Inclusion? Undecided


2020 Thomas Medal Presentation: Keeping Pace with Change
Addressing Materials Challenges and Other Barriers to the Future of Additive Manufacturing
An AI-based Vision Methodology for Self-guided Seam Tracking in Gas Metal Arc Welding
An Investigation into the Effects of Stir Zone Chemistry on Fracture Toughness in Friction Stir Welded Pipeline Grade Steel
Analysis of Temperature and Velocity Fields in the GTAW Arc for Argon
Application of Polarity Switching Capacitor Discharge Welding to Aluminum Sheet Structures
Buried Arc GMAW for Single Pass Single Sided Erection Joints onboard Ships
Carbonitride Development and Heat Treatment Response of Additively Manufactured 17-4 PH Stainless Steel with Variations in Composition
Characterization of Dissimilar Materials 410 Martensite Stainless Steel and Mild Steel Component Produced by Wire Arc Additive Manufacturing
Deleterious Phase Avoidance in Additively Manufactured Functional Gradients through Path Planning
Developing an Automated Defect Detection TIG Welding Robot with a future Adaptive Implementation
Development of a Temperature-Dependent Material Property Database for DH36 Steel
Droplet Temperature in GMAW
Effect of Composition on Solidification Behavior and Resultant Microstructure in Dissimilar Electron Beam Welds between Commercially Pure Iron and Nickel
Energy Balance in Gas Metal Arc Welding
Evaluating the Carbide Precipitation Behavior During Short Term Tempering and its Influence on Impact Toughness.
Evaluation of Spatter Production with Deep Learning Algorithms
Evolution of Analytical Modelling Approaches for Resistance Spot Welding: A Historical Perspective
Fatigue Properties of Dissimilar Aluminum to Steel Welds Joined by Ultrasonic Interlayered Resistance Spot Welding Process
Hardness Prediction by Incorporating Heat Transfer and Molten Pool Fluid Flow in a Multi-pass, Multi-layer Weld for Onsite Repair of CSEF Grade 91 Steel
High Speed Video (HSV) and Synchronized Data Acquisition (DAQ) to Observe Welding Process Stability
How to Accurately Monitor the Weld Penetration from Dynamic Weld Pool Serial Images using CNN-LSTM Deep Learning Model?
Hybrid Manufacturing: Combining Additive Friction Stir Deposition, Metrology, and Machining
IIW Commission I Activities on Additive Manufacturing
Impact of Beam Deflection on Porosity during Keyhole Mode Laser Welding of Aluminum Alloys
In-situ Liquid Nitrogen Cryogenic Cooling for Interpass Control in High-Duty Cycle Wire Arc Additive Manufacturing of Large Components for Navy Applications
Influence of Microstructure on the Mechanism of Hydrogen-assisted Cracking in Dissimilar Metal Welds for Refinery Application
Integrated Modeling of Defect Formation during Deep Penetration Laser Welding of Creep Resistant Nickel Base Alloys
Investigation of Fe-10 wt.% Ni Steel Weld Metal Hydrogen Induced Cracking Susceptibility using the Gapped Bead on Plate (GBOP) Test
Large-Scale Hybrid Manufacturing using Wire Arc Additive Manufacturing
Machine Learning-based Process Characterization and Efficient Adaptive Control in Robotic Arc Welding
Material Characterization of Grade 91 Steel Welds using Micro-resolution Ultrasonic Imaging System.
Mechanical Design and Development of a Five Degree-of-Freedom TIG Welding Robot
Meta-Analysis of Fatigue Properties in Additively Manufactured 316L Austenitic Stainless Steel
Micro Cross Weld Tensile Testing of Dissimilar Metal Welds using Digital Image Correlation
Micro GTAW Applied to a Battery Pack for Racing Applications
Microstructure and Mechanical Properties of Electron Beam Additively Manufactured Ti-6Al-4V
Optimizing Productivity of Hyper Duplex Stainless Steels Overlay while Avoiding Sigma Phase Formation
Phase Transformation Behavior of Fe-10wt.% Ni Steel Weld Metal
Predicting Operation Windows for High-Frequency Induction Aluminum Tube Welding through Machine Learning
Process-Feature-Microstructure-Property Relationships for A9628 Directed Energy Deposition Additive Manufactured Steel Components
Real-Time Recognition of Arc Weld Pool Using Image Segmentation Network
Role of Standards in Welding Safety
Scaling Analysis of Thermal and Mechanical Process in Friction Stir Welding
The Effects of Post-Weld Processing on Friction Stir Welded Additive Manufactured AlSi10Mg
The Influence of Boride Phase Transformations on Heat-Affected Zone Liquation Cracking Susceptibility in Laser Welded 304L Stainless Steel
The Influence of Dynamic Behaviors Characteristics of Molten Pool on the Weld Formation during the High Speed Laser Welding
The International Institute of Welding: Strategic Directions for Welding and Joining Research and Industrial Applications
Use of Low Transition Temperature Steel Alloys In Welded Overlays for High Wear Applications
Welding Investigation of Wrought FeMnAl Steel
WeldVac – A Quiet, Clean Metal Removal System

Questions about ProgramMaster? Contact