skip to main content

SciTech ConnectSciTech Connect

Title: An investigation of the dynamic separation of spot welds under plane tensile pulses

We performed ultra-high-speed tests for purely opening spot welds using plane tensile pulses. A gun system generated a parallel impact of a projectile plate onto a welded plate. Induced by the interactions of the release waves, the welded plate opened purely under the plane tensile pulses. We used the laser velocity interferometer system for any reflector to measure the velocity histories of the free surfaces of the free part and the spot weld of the welded plate. We then used a scanning electron microscope to investigate the recovered welded plates. We found that the interfacial failure mode was mainly a brittle fracture and the cracks propagated through the spot nugget, while the partial interfacial failure mode was a mixed fracture comprised ductile fracture and brittle fracture. We used the measured velocity histories to evaluate the tension stresses in the free part and the spot weld of the welded plate by applying the characteristic theory. We also discussed the different constitutive behaviors of the metals under plane shock loading and under uniaxial split Hopkinson pressure bar tests. We then compared the numerically simulated velocity histories of the free surfaces of the free part and the spot weld of the welded platemore » with the measured results. The numerical simulations made use of the fracture stress criteria, and then the computed fracture modes of the tests were compared with the recovered results.« less
Authors:
; ; ; ;  [1]
  1. Mechanics and Materials Science Research Center, Ningbo University, Zhejiang 315211 (China)
Publication Date:
OSTI Identifier:
22314536
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 5; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; CRACKS; FRACTURES; INTERFEROMETERS; LASERS; METALS; PLATES; PULSES; SCANNING ELECTRON MICROSCOPY; STRESSES; SURFACES; VELOCITY; WELDED JOINTS