Evaluations of stress-free lattice spacings and residual stresses in a quenched carbon steel cylinder using neutron diffraction

Abstract Microstructure-dependent stress-free lattice spacings ( d 0 ) were measured using neutron diffraction in a comb-like specimen fabricated from a quenched carbon steel cylinder. The d 0 values increased with cylinder radius due to the increase in the martensite (α′) fraction with the radius and were comparable to d 0 values calculated using the lattice parameter of each phase, taking the auto-tempering effect into consideration. Using the measured d 0 values, we suggested a relationship between the d 0 and α′ fraction and evaluated macroscopic residual stresses in the quenched steel cylinder.