Residual Stress Measurement of Titanium Casting Alloy by Neutron Diffraction


Neutron stress measurement can detect strain and stress information in deep region because of large
penetration ability of neutron beams.The present paper describes procedure and results in the residual stress
measurement of titanium casting alloy by neutron diffraction. In this study, the three axial method using Hooke's
equation was employed for neutron stress measurement. This method was applied to the cylindrical shape sample of
titanium casting alloy (Ti-6AI-4V). Form the results of this study, this sample has large crystal grain in the inside whole
position, it is assumed this large grain was grown up during casting manufacture process. Furthermore, the peak profile
used to the stress measurement appears in very weak because of the HCP crystal system of titanium character and effect
of large crystal grain. These conditions usually make difficult to measure the accuracy values of residual stresses.
Therefore, it had to spend a long time to measure the satisfied data from titanium sample. Regarding to the results of
stress measurement, the stress values in the cylindrical sample of three directions is almost same tendency, and residual
stresses change from the compressive state in the outer part to the tensile state in the inner part gradually.
Keywords: Titanium, Residual stress, Neutron diffraction, Nondestructive estimation.M. Nishidal,*, T. Jing2, M. R. Muslih3 and T. Hanabusa4
JDepartment of Mechanical Engineering, Kobe City College of Technology, Kobe, Japan
2School of Materials Science and Engineering, Harbin institute of Technology, Harbin, China
3Neutron Scattering Laboratory, BATAN, Kawasan Puspiptek Serpong , Indonesia
4Dept. of Mechanical Engineering, Institute of Technology and Science, Tokushima University, Tokushima, Japan