title: Design and implementation of a multiaxial loading capability during heating on an engineering neutron diffractometer.
abstract: A gripping capability was designed, implemented, and tested for in situ neutron diffraction measurements during multiaxial loading and heating on the VULCAN engineering materials diffractometer at the spallation neutron source at Oak Ridge National Laboratory. The proposed capability allowed for the acquisition of neutron spectra during tension, compression, torsion, and/or complex loading paths at elevated temperatures. The design consisted of age-hardened, Inconel(®) 718 grips with direct attachment to the existing MTS load frame having axial and torsional capacities of 100 kN and 400 N·m, respectively. Internal cooling passages were incorporated into the gripping system for fast cooling rates during high temperature experiments up to ∼1000 K. The specimen mounting couplers combined a threaded and hexed end-connection for ease of sample installation/removal without introducing any unwanted loads. Instrumentation of this capability is documented in this work along with various performance parameters. The gripping system was utilized to investigate deformation in NiTi shape memory alloys under various loading/control modes (e.g., isothermal, isobaric, and cyclic), and preliminary results are presented. The measurements facilitated the quantification of the texture, internal strain, and phase fraction evolution in NiTi shape memory alloys under various loading/control modes.
authors.affiliation: NASA Glenn Research Center, Structures and Materials Division, Cleveland, Ohio 44135, USA.
authors.forename: O
authors.initials: O
authors.lastname: Benafan
authors.affiliation: NASA Glenn Research Center, Structures and Materials Division, Cleveland, Ohio 44135, USA.
authors.forename: S A
authors.initials: SA
authors.lastname: Padula
authors.affiliation: Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors.forename: H D
authors.initials: HD
authors.lastname: Skorpenske
authors.affiliation: Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors.forename: K
authors.initials: K
authors.lastname: An
authors.affiliation: Advanced Materials Processing and Analysis Center, Materials Science and Engineering Department, University of Central Florida, Orlando, Florida 32816, USA.
authors.forename: R
authors.initials: R
authors.lastname: Vaidyanathan