Papers by Author: S. Ganguly

Abstract: This paper summarizes the results of a neutron diffraction study of a single weld bead on a rectangular austenitic stainless steel plate. The measurement was carried out at SALSA, the engineering strain scanner at the ILL, Grenoble, France. The work has been carried out under the European NET project, and is a round robin exercise of residual stress simulation and validation benchmark in a stainless steel bead-on-plate (BOP) weldment. A monochromatic beam of wavelength 1.494 Å was used and the lattice spacing of {311} crystallographic plane was measured. The principal strain measured in the plate was corrected by measuring small cube sample of 3×3×3 mm3 as stress free reference. The measured strain was then used to calculate the principal stress distribution. Finally, the measured strain was compared with the strain measured in a similar specimen in a pulsed neutron source by the time-of-flight (TOF) technique.

Abstract: The residual stress field in a VPPA welded AA2024 coupon sample was measured by neutron diffraction. A similar sample was measured using synchrotron X-rays to determine the inplane strain directions. The macrostrain obtained from both sources compares well in spite of the significant difference in gauge volume and diffraction geometry. The result confirms the repeatability of the weld process and also shows good correspondence between the two diffraction processes.