ICWE Investigations of Thermomechanical Responses in FSP and PVP Failure

Since the Second Industrial Revolution, welding has been an important technique in the engineering toolbox. Novel methods spawn and branch out, offering options each with their own strengths and weaknesses. Constant advancement of technology demands improvements of the methods used in fabrication. Integrated Computational Welding Engineering (ICWE) is a relatively new approach for accelerating understanding of the processing-microstructure-properties relationship for linking welding parameters to weldment performance. This work explores three examples of how ICWE can be used to solve real-world industry issues. Friction Stir Welding (FSW) and Additive Friction Stir Deposition (AFSD) are widely accepted joining techniques, yet mechanisms related to surface conditions, high-stress/temperature deformation, and bonding are not fully understood. In addition, premature failures in pressure vessels and piping systems (PVP) have been attributed to stress relaxation cracking. Trust in accelerated testing, incorporated into initial guidelines, led to premature failure. Understanding how weld behavior changes over different time, temperature, and stress ranges is required to make more accurate predictions. Residual stress fields remain a difficult feature to model and measure with confidence. The use of a plane stress assumption, typically reserved for analyzing stress of thin sheets, is applied to larger bulk structures when measuring residual stress using neutron diffraction.