Probabilistic Assessment of Shot Peening Impact Coverage

Author:  Langdon Feltner and Paul Mort | Purdue University
Source:  The Shot Peener magazine, Vol 39, Issue 2, Spring 2025
Doc ID:  2025011
Year of Publication:  2025
Abstract:  
Introduction In shot peening, compressive residual stresses are induced through impact events between media and the surface of a component. When designing a shot peening machine and specifying operational parameters, practitioners often aim to achieve full and even coverage through sufficiently long cycle times and careful positioning of the peening nozzle with respect to the treated surface. Mass flow rate, peening time, and blast pressure are particularly important when considering impact coverage on a component. Over a peening cycle, a discrete number of particles leave the nozzle, each with an associated mass. For a given substrate material, particle mass, and media hardness, the size of the surface dimple left by an impact is determined by the particle’s velocity, meaning the distribution of dimple coverage is directly related to the uniformity of particle mass flux.