Residual stress analysis in weldments

Residual stress measurement on the butt-welded area by electronic speckle pattern interferometry

“…For shifting the phase, a piezoelectric transducer (PZT) is used and the step movement amount of the phase is p/2. If the intensity distributions of four phaseshifted interference images when an object is in the steady state are I 1 , I 2 , I 3 , and I 4 , then the phase distribution of an object surface can be obtained from Equation 3.…”

“…They may be created by manufacturing processes such as casting, rolling, welding, heat treating, or forging, or may occur during the life of a structural or mechanical component [2,3]. The magnitude and distribution of residual stresses are highly significant and need to be quantified since the mechanical behavior of different materials will be affected when they are present.…”

Synchrotron diffraction measurement of residual stresses in friction stir welded 5383‐H321 aluminium butt joints and their modification by fatigue cycling

“…If such conservatism is to be reduced, more definitive information regarding the magnitude and variability of residual stresses in the as‐welded state is required, together with detailed knowledge of their modification by applied load cycles 3 . The area of residual stress measurement, particularly at welds, and understanding their influence on fatigue life has been a major thread in research for many years 4–7 . Impetus towards more accurate life prediction also derives currently from development of improved aluminium alloy compositions which may offer better parent plate corrosion and fatigue resistance, and from new weld processes, such as friction stir welding, which potentially offer significantly improved productivity and higher levels of joint performance.…”