Spotweld Models for Advanced High Strength Steels


Executive Summary

This is a Phase II (technical feasibility) research project on development and implementation of a novel spot-weld modeling approach for structural analysis. The modeling is supported by the new spot-weld high-rate tests which will result in an interactive test database for various materials and spot-weld configurations. The developed methods will be used in advanced crashworthiness computer aided engineering (CAE) of spot-welded auto-body structures, and will enable more efficient design of structures for light-weighting while meeting crash requirement and cost-effectiveness. Phase I (concept feasibility) of the project successfully carried out the initial development of the Spot Weld Element (SWE) modeling framework and demonstrated of the effectiveness of such modeling approach.

Spotweld Pull-Out

Main project tasks:

  1. Extend the applicability of Spot Weld Element (SWE) to various AHSS spot weld configurations and structural components.
  2. Extend SWE to multi-stack combinations of AHSS,
  3. Develop weld fracture criteria applicable to different loading and fracture modes, and different combination of materials,
  4. Develop a comprehensive impact testing database, and 5. Component level CAE model validation.

The objective is to develop the SWE based on microstructure-property model and implement it in FEM codes. The constitutive models will be based on strain-rate sensitive elasto-plastic fracture and damage mechanics, and the material microstructure. Welding process modeling will account for new materials and spot weld arrangements. The technology commercialization/industrialization plan is to have the SWE modeling framework developed in this project to be transferred and implemented into OEM advanced CAE crashworthiness simulation codes.