Measurement and Functional Approximation of Peening Intensity Distributions

Abstract

In the case of large components, shot peening is generally performed by moving peening equipment that follows a trajectory on the component surface using a robot. In this study, we aimed to obtain a functional approximation of the intensity (arc height of the Almen strip) distributions in the shot stream. The intensity distributions using various peening time and standoff distances were measured under two different experimental conditions. The measured intensity distributions were approximated by modified Gaussian distribution functions, which included the saturation curve. Three coefficients in the functions depended on the peening time and the standoff distance. For tilted shot peening, the intensity distributions were more complex because the standoff distance at each Almen strip was different. The intensity distributions of the tilted plates calculated by the modified Gaussian distribution function, which considered the variation in the standoff distance, were in good agreement with the experimental results. The intensity distributions of twice-shot peening differ from those of once-shot peening because the second peening area overlap with the first peening area. The modified Gaussian distribution function and the saturation function were used to determine the intensity distribution of a twice-shot peened sample. These calculated values were in good agreement with the experimental results.

 

This Paper was Originally Published in Japanese in J. JSTP 59 (2018) 165–170.