Journal of Materials Engineering and Performance

, Volume 24, Issue 12, pp 4710–4720 | Cite as

In Situ Tensile Deformation and Residual Stress Measurement by Neutron Diffraction in Modified 9Cr-1Mo Steel

  • Triratna Shrestha
  • Indrajit CharitEmail author
  • Gabriel Potirniche


The deformation behavior of monolithic modified 9Cr-1Mo (Grade 91) steel during uniaxial tensile loading was studied using the in situ neutron diffraction technique. The residual stress distribution across gas tungsten arc welds in the Grade 91 steel was measured by the time-of-flight neutron diffraction method using the SMARTS diffractometer at Lujan Neutron Scattering Center, Los Alamos National Laboratory. Grade 91 plates were welded using the gas tungsten arc welding (GTAW) technique. The load sharing by different grain orientations was observed during the tensile loading. The residual stresses along three orthogonal directions were determined at the mid-thickness, 4.35 and 2.35 mm below the surface of both the as-welded and post-weld heat-treated plates. The residual stresses of the as-welded plates were compared with those of the post-weld heat-treated plates. The post-weld heat treatment significantly reduced the residual stress level in the base metal, the heat-affected zone, and the weld zone. Vickers microhardness across the weld zone of the as-welded and post-weld heat-treated specimens was evaluated and correlated with the observed residual stress profile and microstructure.


modified 9Cr-1Mo neutron diffraction residual stress steel welding 



This work has benefited from the use of the SMARTS facility at the Lujan Neutron Scattering Center at Los Alamos Neutron Science Center, funded by the DOE Office of Basic Energy Sciences. Los Alamos National Laboratory is operated by Los Alamos National Security LLC under DOE Contract DE-AC52-06NA25396. This research was performed using funding received from the DOE Office of Nuclear Energy’s Nuclear Energy University Programs (NEUP) through the US Department of Energy Grant no. 42246 release 59. The first author (TS) would like to acknowledge the assistance provided by Bjorn Clausen, Donald W. Brown, and Thomas A. Sisneros of the Lujan Scattering Center during the course of this study.


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Copyright information

© ASM International 2015

Authors and Affiliations

  • Triratna Shrestha
    • 1
    • 3
  • Indrajit Charit
    • 1
    Email author
  • Gabriel Potirniche
    • 2
  1. 1.Department of Chemical and Materials EngineeringUniversity of IdahoMoscowUSA
  2. 2.Department of Mechanical EngineeringUniversity of IdahoMoscowUSA
  3. 3.Integrated Global ServicesRichmondUSA

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