Simulation of the micro–Single Point Incremental forming process of very thin sheets
Résumé
The purpose of this paper is to simulate a complex forming process with
parameters identified from tensile and shear tests. An elastic-plastic
model is retained which combines a Hill’s 1948 anisotropic criterion and
plastic potential using a non-associated flow rule. Firstly, a
mechanical characterization is made with homogenous tests like tensile
and shear tests [1]. On the other hand a process of micro Single Point
Incremental forming is simulated [2]. It consists in deforming a clamped
blank using a hemispherical punch which has a small diameter compared
to the blank dimensions. From a small-size sheet of 0.2 mm thick, a
square-based pyramid is obtained incrementally, with a define height
path and advanced speed, by a tool instrumented to measure the forming
force, which deforms locally the material. It is shown that the
non-associated flow plasticity model leads to a good agreement between
experimental and numerical results for the evolution of the punch force
during the process.