skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Tomographic imaging of noncircular and irregular electron beam current density distributions

Journal Article · · Welding Journal (Miami); (United States)
OSTI ID:5843519
; ;  [1]
  1. Lawrence Livermore National lab., Livermore, CA (United States)

A computer tomography (CT) diagnostic method is presented for high resolution imaging of the current density distribution in electron beams. This technique measures the electron beam (EB) profile by integrating the current density of the beam along a thin slit, and CT reconstructs the current density distribution form multiple profiles taken at equally spaced angles around the beam. Computer tomography imaging allows the current density distribution of noncircular and irregular electron beams to be accurately measured in order to characterize the quality of the electron optical system and the quality of the electron beam. In this investigation, sharp focused and defocused multi-kilowatt electron beams, produced by hairpin and ribbon filaments, were examined using CT imaging to illustrate the differences that exist between the current density distributions produced by these different filament shapes. The results of this investigation further showed the influence that beam current and beam focus have on the peak power density and the power density distribution of both hairpin and ribbon filaments. When used for process control and beam diagnostics, CT imaging will assist with the accurate transfer of welding parameters to different machines, improve the understanding of electron-beam/material interactions, and help to generate tailored power density distributions for improved electron beam welding and surface treating of materials.

DOE Contract Number:
W-7405-ENG-48
OSTI ID:
5843519
Journal Information:
Welding Journal (Miami); (United States), Vol. 72:11; ISSN 0043-2296
Country of Publication:
United States
Language:
English