Single-test determination of the friction coefficient and stress-strain curve for application in metal-forming analyses

The compression test of a ring is customarily used to determine the frictio n coefficient in metal-forming problems. The aim of this paper is to descri be a procedure to obtain, for metals in the large deformation range, the st ress-strain curve and friction coefficient through the same test. The frict ion coefficient is evaluated by comparing curves obtained by a finite eleme nt code with the experimental curves. The stress-strain curve is obtained b y inverting an analytical solution, calculated by a lower-upper-bound appro ach. Good results in terms of accuracy are obtained.