Multi?scale model predicting friction of crystalline materials

A nonlocal multiscale discrete-continuum model for predicting mechanical behavior of granular materials

A three-dimensional nonlocal multiscale discrete-continuum model has been developed for modeling mechanical behavior of granular materials. In the proposed multiscale scheme, we establish an informationpassing coupling between the discrete element method, which explicitly replicates granular motion of individual particles, and a finite element continuum model, which captures nonlocal overall re...

Multiscale Design of Materials

Current methods of materials development, relying mostly on experimental tests, are slow and expensive, often taking over a decade and costing many millions of dollars to develop and certify new materials for critical applications. Finding new approaches for materials development is essential. Moreover, it will be increasingly important for materials development to be integrated into overall pr...

Multiscale Surfaces and Amontons’ Law of Friction

The theories of Archard, Greenwood, and more recently Persson all predict that the area of actual contact between two rough surfaces will be approximately proportional to the applied normal force, though these authors make different assumptions and approach the problem from different points of view. Here we discuss the nature of these approximations and show that the common conclusion follows f...

Electronic Structure of Crystalline Materials

Multiscale Friction Modeling for Sheet Metal Forming

The most often used friction model for sheet metal forming simulations is the relative simple Coulomb friction model. This paper presents a more advanced friction model for large scale forming simulations based on the surface change on the micro-scale. The surface texture of a material changes when two surfaces are in contact under a normal load. This is caused by flattening due to combined nor...