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Abstract Shot peening (SP) is one kind of effective mechanical surface treatment to improve the surface mechanical property. Increasing SP intensity can not only introduce compressive residual stresses into the layer near the treated surface, but also produce nanocrystalline layer near the treated surface. This paper investigated the method of predicting the generation of refined grains after high energy shot peening (HESP) proposed by previous works. In that method, the equivalent plastic strain (PEEQ) was considered as a critical value for estimating the grain refinement level. The main contribution of this paper was to prove the applicability of the proposed method of predicting nanostructured surface layer in different HESP conditions via a HESP model with different numbers of shots and impact patterns. The simulated results show the ultimate PEEQ value is independent of the element size in all HESP conditions, which confirms this method is a practical and effective tool to evaluate surface nanocrystallization phenomenon during HESP process. Highlights • The universality of the method of predicting nanostructured surface layer in high energy shot peening (HESP) process has been proved via establishing different HESP models with different numbers of shots and impact patterns. • This work confirms that the real maximum equivalent plastic strain (PEEQ) value is independent of the element size in all HESP conditions. • The real maximum PEEQ value can be obtained via the extrapolation method if three arbitrary different maximum PEEQ values are obtained. • Compared with increasing the number of shot impacting, increasing the overlap rate of dimples' coverage makes the PEEQ increase more significantly. [ABSTRACT FROM AUTHOR]

Abstract Spot continual induction hardening (SCIH) is one kind of selective surface treatments, which has been proven to be appropriate for improving the tribological property and the fatigue behavior of specific areas of treated components. In our work, an electromagnetic-thermal-mechanical-metallurgical coupled numerical model was developed based on a novel co-simulation of ANSYS and ABAQUS/standard via making use of these two commercial finite element softwares' respective advantages to describe the SCIH process. The simulated results agreed well with experimental data in temperature development and the distributions of hardness, phase and residual stresses. The relationship between the inductor velocity and surface characteristics was discussed and the optimization of induction coil velocity was carried out based on the validated numerical model. Highlights • A novel numerical model was developed for SCIH process via co-simulation of two FEM softwares. • The proposed model can predict the distributions of hardness, phase and residual stresses after SCIH. • The beneficial residual stress distribution can be obtained via SCIH process with a relatively low velocity of inductor. [ABSTRACT FROM AUTHOR]