The use of lightweight materials in vehicles will significantly increase fuel efficiency and cut emissions, but the auto industry lacks data and material models needed to reliably manufacture vehicle components from lightweight substitute materials. Traditional finite element models can validate NIST developed constitutive models for certain materials by applying such models for experiments involving loading of uniaxial and/or biaxial specimens. Validated constitutive models can allow US automakers to use these advanced lightweighting materials without expensive die tryouts and new model development costs. In addition, CP-FEM (crystal plasticity-finite element method) modeling allows development of constitutive laws for new materials based on the initial crystallographic texture and uniaxial stress-strain data, thereby predicting the evolution of the yield surface in multi-axial tensile space for a real specimen. Computed constitutive models will be validated by comparing predicted results with experimental measurements. Such validated tools will enable US automakers to incorporate new, advanced lightweighting materials with varying crystallographic texture in vehicle components.

 

key words

Auto industry; Lightweighting materials; Finite elements; Crystal plasticity modeling; Constitutive models; Yield surface; Crystallographic texture;

Citizenship:  Open to U.S. citizens

Level:  Open to Postdoctoral applicants