X-Ray Stress Estimation of Carbide in Spheroidized JIS SK5 Steel

Abstract

The low volume fraction of carbide phase in carbon steel determines that it is difficult to estimate the stress state in it by diffraction method. In the present study, different from the studies before, we improve the technique of surface treatment on specimen and have successfully finished the stress estimations of carbide phase in carbon steels by X-ray diffraction method under normal conditions. Moreover, we investigate the affection of spherical cementite particle size on the residual stress distribution in both phases during the plastic deformed steels. We observed that the steels with small-sized cementite particles showed higher stress states than the steels with relatively large-sized cementite particles.

Microstructure-Based Computational Simulation and Experimental Measurement of Stresses in Spheroidized Steels

“…Specimens used for the experiment are 60 mm in length, 10mm in width and 3mm in thickness. The specimens are spheroidizing annealed to form cementite particles with large (SL) and small (SS) spheriodal structures [2]. Final micrographs and mechanical properties of four different kinds of specimen are listed in Table 1.…”

“…The stresses in two phases are measured axially to the applied loading direction of the specimens. Before the X-ray measurement, the specimen surface is treated previously as described in our previous paper [2]. The ferrite and…”

“…It mixes with ferrite, the other product of austenite, to form lamellar structures called pearlite and bainite. It has been introduced in previous studies that microstructural features of cementite particles have obvious effects on the internal stresses generated during the plastic deformation of steels, and the stress states are attributed to the inhomogeneous mechanical properties of steels [2,3]. Lee et.al [4] have evaluated the effects of the carbon content, strain rate and temperature on the mechanical responses of the steels and found that an increase of carbon content enhanced the dynamic flow resistance of steels.…”