Ductility and Strength Properties of Shot Peened Surfaces

Author:  Dr. David Kirk
Source:  The Shot Peener magazine, Vol 20 / Issue 2, Spring 2006
Doc ID:  2006051
Year of Publication:  2006
Abstract:  
INTRODUCTION It is an apparent paradox that peening, which requires a large degree of ductility, can readily be applied to high-strength, low ductility, engineering components. A single indentation may induce plastic deformations of more than 100%. This is illustrated in fig.1 where it is assumed that the depth of the deformed zone is twice that of the indentation itself. A column of length AC has been compressed to half of its height BC. The deformed column therefore has an average compressive plastic deformation equivalent to a tensile deformation of 100% (using engineering strain calculation). That deformation varies from 0% at C (the boundary of the plastically-deformed zone) to a maximum at B. Assuming a simple linear variation, that will equate to 200% at B.