Computational Solid and Structural Mechanics*

Laser welding of dual-phase steel

In this project, our goal was to minimize distortion during laser welding of dual-phase steel sheets:

• A temperature dependent thermo-mechanical numerical model was developed
• The numerical model was capable of predicating different phases of steel
• Mechanical testing was performed
• Advance materials characterization was conducted 

Publication/Thesis:

Esmaeilpour R., Alah Nazari Tiji S., Nassiri A., "Microstructure and Mechanical Behavior of Laser Welded Dual-Phase DP590 Steel- Experimental and Numerical Investigation" (in preparation)

Feasibly study of foldable bike helmet

In this project we developed a computational model to investigate the feasibility of a foldable bike helmet made from laminated polyester fabric:

• A finite element model was developed from scratch
• Mechanical testing was conducted to identify the fabric’s properties required for modeling
• The model was tested for various impact scenarios

 Numerical simulation of high-velocity impact welding process

In this project, we developed a computational platform using meshfree technique to identify weldability between Aluminum/High-strength steel and Copper/Titanium:

• A non-linear finite element model was developed
• The model was validated by performing experimental tests with different process parameters including impact velocity and impact angle
• SEM, EBSD, and TKD analyses were performed in collaboration with The Ohio State University, Welding Engineering Department

Publication/Thesis:

• Nassiri A., Abke T., Daehn G., 2019, "Investigation of melting phenomena in solid-state welding processes", Scripta Materialia, 168, 61-66. (link)
• Nassiri A., Vivek A., Abke T., Liu B., Lee T., Daehn G., 2017, “Depiction of interfacial morphology in high-velocity impact welded Ti/Cu bimetallic systems using smoothed particle hydrodynamics”, Applied Physics Letters (110), 23, 1601. Featured on the cover. (link)
• Nassiri A., Zhang S., Lee T., Abke T., Vivek A., Kinsey B., Daehn G., 2017, “Numerical investigation of CP-Ti & Cu110 impact welding using Smoothed Particle Hydrodynamics and Arbitrary Lagrangian-Eulerian methods”, Journal of Manufacturing Processes, 28, 558-564. (link)

AI-enhanced patient-specific biomechanical models to predict fracture risk and optimize limb sparing in giant breed dogs with appendicular osteosarcoma

This proposal will develop an approach to generate patient-specific biomechanical models to predict pathologic fracture following limb-sparing radiation therapy. We will:

• Construct the benchmark non-linear finite element analysis (FEA) model from patient computed tomography scans using AI algorithms that can accurately predict bone fracture risk by creating a patient-specific model.
• Validate the model by creating patient-specific models for historic clinical cases that received baseline CT and SBRT, and have clinical follow up to determine if fracture occurred.
• Modify AI-enhanced FEA models to include stabilization with IS implant and establish adequate stabilization for surgical planning

Current team members

Ali Nassiri, Research Assistant Professor, Integrated Systems Engineering
Scott Noll, Research Assistant Professor, Mechanical and Aerospace Engineering
Peiyu Yang, SIMCenter, Research Specialist