A quasi-coulomb model for frictional contact interfaces. Application to metal forming simulations

Frictional contact interfaces have to be modeled in practice when industrial problems such as metal forming operations, crashworthiness, and so on, have to be simulated. Usually a Coulomb model is used in order to describe the constitutive law for the frictional case. Following a standard non associated plasticity approach to Coulomb law a non-symmetric tangent operator results, and so a non-symmetric solver has to be used in order to take full advantage of consistent operators. With respect to symmetric ones, these non-symmetric operators lead to prohibitive computational times. However, in practice different schemes have been proposed in order to recover the symmetric operator, and consequently, use a symmetric solver. In this work an alternative approach based on an idea due to Garcia Garino and Oliver (1992) is defined in order to avoid to deal with non-symmetric solvers and thus save a large amount of computational time, which renders the computational simulation more attractive to industry. Applications to metal forming simulations and crashworthiness analysis are considered.