Issue 46

A. Baltach et alii, Frattura ed Integrità Strutturale, 46 (2018) 252-265; DOI: 10.3221/IGF-ESIS.46.23 254 100 %    d dD i (1) Figure 1 : Geometry and dimensions of holed plate (Dimensions are in mm). a) b) Figure 2 : Mandrels used for the expansion: a) rigid tapered pin and b) rigid ball. In order to analyze the effect of taper parameters of the tapered part of the pin, we considered several cone lengths. Thus, the taper λ% parameter is calculated as follows: 100 %    L dD  (2) where, L is the length of the tapered part as shown in Figs. 3a and 3b. Fig. 3a shows the geometric details of the tapered part of the mandrel. Thus for example, for L = 3 mm, the degree of taper λ = 7.667 %. a) b) Figure 3 : Geometry definition of the tapered pin: a) Taper Details of the conical part of the pin mandrel, Case of L = 3 mm; b) Geometry and dimensions of the tapered pin. Tab. 1 summarizes the different tapers used in this work corresponding to lengths L=2, 6, 8 and 10 mm as to be used in the presentation legend of the results.