Papers by Keyword: Dynamic Material Model

Abstract: A precise description of the hot deformation behavior as well as determination of the stability conditions as influenced by temperature and strain rate is fundamental for the simulation of metal forming processes. In this work, a revision of various stability criteria of magnesium alloy WE54 is conducted. The study corresponds to own work and that of Lentz et al. and is based on compression tests at high temperature and high strain rates. Stability and processing maps were obtained using a variety of stability criteria, some based on the efficiency parameter η and others on the strain rate sensitivity parameter, m. This parameter is usually determined by fitting the curves strain rate, ε, versus stress, σ, by means of a potential equation named “power law” or by a polynomial of second or third degree, and calculating the slope of the logarithmic curve at each point using successive derivatives. This procedure is compared with one developed by us where all experimental points are fitted to a single hyperbolic sine equation of Garofalo type and then m and η are calculated for each ε and T using this equation. The maps obtained by one or the other method differ considerably. The predictions of these maps were contrasted with microstructural observations and conclusions on the deformation behavior of the alloy are reached.

Abstract: Brick masonry is a traditional building material widely used loading-bearing or partition walls in various building structures. The detailed distinctive modelling of brick and mortar of a realistic masonry structure or a structure with masonry infilled walls are usually not possible due to the computational cost. In this paper, a homogenized dynamic material model which including the damage of brick and mortar and strain rate effect is developed based on dynamic test results of brick and mortar. The proposed homogenized material model was used in analysis of blast response of brick masonry wall.