681910.fig.009a
(a)
681910.fig.009b
(b)
681910.fig.009c
(c)
681910.fig.009d
(d)
Figure 9: Influence of rotational speed on (a) weld yield strength, (b) weld Young’s modulus, (c) yield strength to Young’s modulus ratio, and (d) weld strain hardening exponent; SD: shoulder diameter (in mm); WS: welding speed (in mm/min).