**5.3. Tensile tests**

242 Mechanical Engineering

500 x 500 x

500 x 500 x

500 x 500 x

Fig. 7. Microstructure of all surface welded layers (Popovic et al.,2007).

1. layer

2. layer

3. layer Sample 1 Sample 2

The tensile tests were conducted on a 2 mm thick specimens. The room temperature mechanical properties (ultimate tensile strength, UTS) of the surface welded joint are shown in Figure 8. The basic requirement in welded structures design is to assure the required strength. In most welded structures this is achieved with superior strength of WM compared to BM (overmatching effect), and in tested case this is achieved (Burzic & Adamovic,2008; Manjgo et al.,2010). The highest UTS is in weld metal of sample 2 (1210 MPa), due to solid state strengthening by alloying elements.

Fig. 8. Ultimate tensile strength of the surface welded joints (Popovic et al.,2011).
