Issue 54

I. Chekalil et alii, Frattura ed Integrità Strutturale, 54 (2020) 153-168; DOI: 10.3221/IGF-ESIS.54.11

E XPERIMENTAL METHOD

T

he friction stir welds were produced on a vertical milling machine using the friction stir welding tool presented in Fig. 1. In order to choose the FSW welding tool, preliminary tests were carried out on the tool itself; the geometry adopted is similar to that of a conical pin ( 5 d mm  and 6.8 D mm  , length 1.7 mm  with a 19.5 mm diameter flat shoulder), made out of X210Cr12 steel with a tensile strength TS = 870 MPa.

Figure 1: Tool geometry

Two AA 3003 aluminum plates, of dimensions 210 mm x 110 mm and 2 mm thick, were joined along the rolling direction using the friction stir welding process. The initial joint configuration was obtained by securing the plates in position using mechanical clamps. Single-pass welding procedure was followed to fabricate the joints (Fig. 2-a). The cutting operation of samples on the welded plates is shown in the diagram presented in Fig. 2-b, where the geometric dimensions are expressed in mm.

Figure 2: (a) FSW configuration; (b) Cutting of samples on welded plates according to 8 8 ASTM E M (dimensions in mm) The tensile tests were carried out on an INSTRON tensile machine, controlled by the MTS software, as shown in Fig. 3. The chemical composition and mechanical properties of the base material before welding are reported in Tabs. 1 and 2. The chemical composition was obtained by SEM-EDX (Scanning Electron Microscopy - Energy Dispersive X-ray Analysis) method.

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