Numerical studies on mixed mode fracture behavior of dissimilar (AISI 304 and AA1050) welded joints with multiple cracks

• Published in: Welding in the world 2018-05, Vol.62 (3), p.565-579
• Main Authors: S, Suresh Kumar, V, Naren Balaji, P.M, Prrithvi
• Format: Article
• Language: English
• Subjects: Aluminum; Aluminum base alloys; Aspect ratio; Austenitic stainless steels; Chemistry and Materials Science; Dissimilar material joining; Fracture mechanics; Heat flux; Materials Science; Metallic Materials; Plates (structural members); Research Paper; Residual stress; Solid Mechanics; Stress intensity factors; Structural integrity; Surface cracks; Theoretical and Applied Mechanics; Welded joints
• ISSN: 0043-2288; 1878-6669
• DOI: 10.1007/s40194-018-0550-5

Effect of residual stresses on mixed mode stress intensity factor (SIF) of dissimilar welds (steel AISI 304 and aluminum AA1050) has been investigated numerically. Opposite surface cracks of various crack depth ratio [(a/t); “a” crack depth, “t” plate thickness] and crack aspect ratio [(a/c); “c” semi-major axis of the ellipse] were considered for different heat flux values. The geometry correction factor (Y) was determined with consideration of mode II and mode III fracture. It is noted that, at short crack depths, as the residual stress increases, SIF of steel region decreases and increases for aluminum region. When the crack depth ratio increases, SIF of both materials decreases due to relieving of residual stress at higher crack depths. Non-uniform crack opening was observed along the crack border, front, and rear side of the plate. A three-parameter relationship has been arrived to determine the structural integrity of dissimilar welded joint.