EWI’s modeling group empowers our customers by innovating fast, accurate techniques to predict welding-induced distortion, weld-metal and heat-affected zone (HAZ) microstructures, material properties, and fatigue life. These predictions allow welding variables to be quickly optimized, reducing distortion by as much as 50%.
This is important since welding-induced distortion often leads to overwelding when ill-fitting sub-structures are joined together during fabrication. As high-strength steels and aluminum alloys are increasingly used in welded structures, meeting part-tolerance and joint-performance requirements becomes significantly more challenging. While these alloys enable the use of thinner, lighter materials, reducing the material thickness often leads to a significant increase in welding-induced distortion. Further, many welding processes detrimentally affect the mechanical properties of these alloys, particularly in the heat affected zone (HAZ).
To speed product development and reduce fabrication costs, EWI has developed modeling and simulation software tools for integrated computational materials engineering (ICME). This approach unifies numerical models, material considerations, design concepts, fabrication techniques, and computational power in a virtual environment.
EWI’s modeling group has developed advanced and fully integrated thermal, metallurgical, and mechanical computational simulation tools for welded structure design and manufacturing process modeling. These computational tools have been successfully used to predict and evaluate product performance, optimize weld design for new product development, and develop manufacturing procedures. EWI’s modeling group works closely with our experts in design, materials, manufacturing, and fitness-for-service to provide a variety of services and support all aspects of our business. The following list provides a sample of our technical expertise.
- Finite-element analysis
- Customized software development and deployment
- Enterprise-level web-based modeling solutions
- Modeling heat transfer and fluid-flow to predict temperature and material flow
- Microstructure and hardness prediction for carbon and low-alloy steels
- Prediction of manufacturing process-induced stress and distortion
- Welding sequencing and fixture design to reduce residual stresses and distortion
- Fracture mechanics analysis to predict crack initiation and propagation
- Thermal cutting
- Arc welding processes
- Laser and electronic beam welding
- Resistance and friction welding processes
- Post-weld heat treatment
- Forming (mechanical and thermal)
- Induction heating
- Magnetic-pulse applications
- Ultrasonic applications
- Additive manufacturing processes
EWI-developed Modeling Tools
- Automatic Thermal Plate Forming (ATPF): Allows plate to be formed into a desired shape using an automated induction-heating system by predicting the required heat patterns.
- WeldFEA: Thermal-metallurgical-mechanical analysis tool to model solid-state and fusion welding processes, allowing the prediction of temperature, microstructure, hardness, residual stresses, and distortion.
- Q-Weld: Simplified, fast weld-distortion prediction tool up to two orders of magnitude faster than WeldFEA.
- EWI WeldPredictor: Automated online-based numerical weld-modeling software.
- Laser link processing simulation (LLPS): Couples optical, thermal, and mechanical models to simulate the repair and programming process of computer memory chips.
Commercially Available Software
- MS.Software (Marc, Nastran, and Patran)
EWI’s innovative modeling group has developed a number of unique capabilities which have had a significant positive impact on our customers. Examples of our innovation include:
- Improving modeling of Laser Powder Bed Fusion (L-PBF) using a plastic strain-based method to predict distortion of full-sized components with a significantly reduced computation time.
- Investigating improved integrated computational materials engineering (ICME) methods to shorten product/process development times by predicting material properties from microstructure, integrating numerical models, and developing experimental validation methods.
- Developed thermos-mechanical modeling for a manufacturer of nuclear piping and pressure vessels to create controlled-heat-input cladding and buttering procedures that eliminate ductility-dip cracking and solidification cracking.
- Predicting of welding-induced distortion in large, complex structures, as well as evaluation of multiple distortion control techniques, including design optimization, pre-straining, sequencing, and pre-cambering.
- Creating an efficient and accurate alternative to using full thermo-elastic-plastic analyses for predicting distortion on complex structures, significantly reducing computation time to allow optimization of welding variables including assembly sequencing and weld sequencing.
- Developing a quick weld-distortion prediction tool (Q-Weld) with funding from the Navy ManTech Program of the Office of Naval Research, allowing efficient optimization of welding sequences, weld fixture design, and the development of new techniques such as transient thermal tensioning (TTT) and pre-cambering.
- Incorporating residual weld stresses into fatigue-life assessment techniques to more accurately estimate crack initiation and propagation life behavior.
- Developing innovative application of ICME methods to optimize welding sequence and fixture design to control residual stress and distortion, design large high-temperature vessels to minimized thermal stress and deformation, and analyze welded-structure failures to propose practical solutions and improve fatigue life.