USING WELDING SIMULATION AND ULTRASONIC METHOD TO EVALUATE RESIDUAL STRESS IN STAINLESS STEEL WELDED PLATES

摘要

When a material is under mechanical load, the stresses change the velocity of acoustic waves because of acoustoelastic effect. This property can be employed for stress measurement in the material itself when the stress concerns the surface of the material, or in the bulk material. This technique involves with critically refracted longitudinal waves that propagate parallel to the surface, i. e. L_(CR) waves. This paper presents a three dimensional thermo-mechanical analysis to evaluate welding residual stresses in plate-plate joint of AISI stainless steel 304L. After finite element simulation, the residual stresses were evaluated by L_(CR) ultrasonic waves. This paper introduces a combination of "Finite Element Welding Simulation" and "Ultrasonic Stress Measurement using the L_(CR) Wave" which is called as "FEL_(CR)". The capabilities of FEL_(CR) in residual stress measurement are confirmed here. It has been shown that predicted residual stress from three dimensional FE analyses is in reasonable agreement with measured residual stress from L_(CR) method.