Measurement and modelling of the residual stresses in autogenous and narrow gap laser welded AISI grade 316L stainless steel plates. (November 2016)

• Record Type: Journal Article
• Authors: Elmesalamy, A.S.; Abdolvand, H.; Walsh, J.N.; Francis, J.A.; Suder, W.; Williams, S.; Li, L.
• Is Part Of: International journal of pressure vessels and piping. Volume 147(2016)
• Page Start: 64
• Page End: 78
• Publication Date: 2016-11
• Subjects: Computational weld mechanics -- Multi-pass laser welding -- Narrow gap welding -- Numerical simulation -- Structural integrity -- Weld integrity; Pressure vessels -- Periodicals; Pipe -- Periodicals; Récipients sous pression -- Périodiques; Tuyaux -- Périodiques; Pipe; Pressure vessels; Periodicals; 681.76041
• DOI: 10.1016/j.ijpvp.2016.09.007
• Languages: English
• ISSNs: 0308-0161

Abstract

Abstract: Thick-section austenitic stainless steels have widespread industrial applications, where stress-corrosion cracking is often of major concern. Problems tend to arise in the vicinity of welds, where substantial residual stresses often reside. This paper describes an investigation into the residual stresses in autogenous high power laser welds and narrow gap laser welds (NGLW) in 10 mm thick AISI grade 316L steel plates, using both neutron diffraction and the contour method. The influences of laser power, welding speed and the time interval between weld passes on residual stress were analysed. For the NGLW process, finite element modelling was employed to understand the influence of thermal history on residual stress. The results for the NGLW technique show that the laser power has a significant effect on the peak value of residual stress, while the welding speed has a more significant influence on the width of the region sustaining tensile stresses. Highlights: We compare the residual stress behaviour in high power autogenous laser welding and Narrow gap laser welding [NGLW] of 10 mm thickplates of 316L stainless steel. We use contour method for residual stress evaluation. The results have been validated by using neutron diffraction. The experimental results show that, lower residual stress distribution can be achieved by using the NGLW technique. We investigate the influence of the power and speed on both peak value and width of the tensile region for both autogenous laser welding and NGLW technique. The welding speed in NGLW technique has a more significant influence on the width of the tensile region. The laser power shows a more significant influence on the peak value of the residual stress with respect to width of the residual stress tensile region.